1 Steam Cars : Phorum
General Steam Car topics
Solid Axle vs. Independent Suspension
Posted by: Peter Brow (IP Logged)
Date: July 14, 2003 07:27AM
<HTML>Hi Everybody,
Terry Williams looked at my latest steam page [www.angelfire.com] and asked me under the Stanley Hotel thread why I am planning to use a solid rear axle instead of easily-available independent rear suspension components. I'm starting a new thread for this topic, in case anyone is interested in discussing it. What are you guys planning or running in the final drive/suspension department?
Hi Terry,
I hear ya on available IRS components. I have two complete spare VW Type 1 transaxles & suspensions in the shop -- can't get more available than that! I spent a couple years looking at this way and that way to adapt them (and some other IRS systems) to steam. Ended up choosing between high-speed engines and redundant gears, both with too much friction and design/fabrication difficulty for my taste. A better way would be cutting off the gearbox and/or making a whole new IRS diff housing, but that raises problems too and isn't much easier, if at all, than building a custom solid axle.
Keep in mind that I don't have decades of experience building and running steam vehicle engines, boilers, etc like you and the other accomplished steam developers, so I am trying to keep my first project as simple and basic as possible. So far I've only designed/built a couple toy boilers & engines, and experimented with small vaporizing burners. Long way to go before I can start untangling the mysteries of IRS and other modern equipment. Solid axles are the choice of most first-project novice hot-rodders for similar reasons. Instant rear wheel alignment, and "so simple even I can do it". At least I'm not using some heavy axle for 3-ton trucks like they do.
Which, come to think of it, makes me wonder about the US automakers. A huge percentage of the hottest-selling new American vehicles in this age of SUVs now have solid axles; what's _their_ excuse? I thought they were only dummies when it came to steam cars. Now Detroit can't design IRS systems anymore either?
Current plan is to use the axle shafts, differential, bearings, etc, of a swing-axle VW IRS system, mounted in a custom solid axle housing instead of in the original IRS transaxle/suspension with gearbox. I may use different innards for the axle, but it's nice to use running equipment which is on hand whenever possible.
This approach is far from ideal, but it allows isolating the engine from the car frame, so that a Stanley-type engine (based on available tested plans) can be used without excessive vibration. That way I can cut out a lot of engine design work and get smooth running sooner.
No approach to building a steam car is anywhere near easy, including this one; this one just seems less difficult & time consuming than the others. I've spent many years on false starts and projects killed by engine design problems before I ever got to the shop. Wish I'd taken this approach 10 years ago; I'd probably have a running car(s), more design/fabrication confidence, & road experience by now, and maybe a second generation design (possibly with IRS), instead of just first-try ideas, blueprints, and mockups. Then again, I've learned a LOT in the past 10 years -- thru extensive historical and theoretical study, I think I've finally reached the very bottom of the even steeper _practical_ learning curve. It's like climbing the Matterhorn to get to the foot of Mt. Everest. :)
Peter</HTML>
Terry Williams looked at my latest steam page [www.angelfire.com] and asked me under the Stanley Hotel thread why I am planning to use a solid rear axle instead of easily-available independent rear suspension components. I'm starting a new thread for this topic, in case anyone is interested in discussing it. What are you guys planning or running in the final drive/suspension department?
Hi Terry,
I hear ya on available IRS components. I have two complete spare VW Type 1 transaxles & suspensions in the shop -- can't get more available than that! I spent a couple years looking at this way and that way to adapt them (and some other IRS systems) to steam. Ended up choosing between high-speed engines and redundant gears, both with too much friction and design/fabrication difficulty for my taste. A better way would be cutting off the gearbox and/or making a whole new IRS diff housing, but that raises problems too and isn't much easier, if at all, than building a custom solid axle.
Keep in mind that I don't have decades of experience building and running steam vehicle engines, boilers, etc like you and the other accomplished steam developers, so I am trying to keep my first project as simple and basic as possible. So far I've only designed/built a couple toy boilers & engines, and experimented with small vaporizing burners. Long way to go before I can start untangling the mysteries of IRS and other modern equipment. Solid axles are the choice of most first-project novice hot-rodders for similar reasons. Instant rear wheel alignment, and "so simple even I can do it". At least I'm not using some heavy axle for 3-ton trucks like they do.
Which, come to think of it, makes me wonder about the US automakers. A huge percentage of the hottest-selling new American vehicles in this age of SUVs now have solid axles; what's _their_ excuse? I thought they were only dummies when it came to steam cars. Now Detroit can't design IRS systems anymore either?
Current plan is to use the axle shafts, differential, bearings, etc, of a swing-axle VW IRS system, mounted in a custom solid axle housing instead of in the original IRS transaxle/suspension with gearbox. I may use different innards for the axle, but it's nice to use running equipment which is on hand whenever possible.
This approach is far from ideal, but it allows isolating the engine from the car frame, so that a Stanley-type engine (based on available tested plans) can be used without excessive vibration. That way I can cut out a lot of engine design work and get smooth running sooner.
No approach to building a steam car is anywhere near easy, including this one; this one just seems less difficult & time consuming than the others. I've spent many years on false starts and projects killed by engine design problems before I ever got to the shop. Wish I'd taken this approach 10 years ago; I'd probably have a running car(s), more design/fabrication confidence, & road experience by now, and maybe a second generation design (possibly with IRS), instead of just first-try ideas, blueprints, and mockups. Then again, I've learned a LOT in the past 10 years -- thru extensive historical and theoretical study, I think I've finally reached the very bottom of the even steeper _practical_ learning curve. It's like climbing the Matterhorn to get to the foot of Mt. Everest. :)
Peter</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: Terry Williams (IP Logged)
Date: July 14, 2003 06:51PM
<HTML>Peter,
I believe you are right to take the shortest route at this point. I think, given what you have on hand, however, I would give a hard look at your VW transaxle. I'd probably just cut off the trans housing, weld on a plate and go to it. You have to be kind of careful with true swing axles though, the outer wheel in a turn tends to turn under. There were aftermarket devices to take care of that though.
Detroit is using solid axle housings I expect to widen their profit margin. The vehicles are fairly heavy too, so unsprung weight not that big a proportion of total.</HTML>
I believe you are right to take the shortest route at this point. I think, given what you have on hand, however, I would give a hard look at your VW transaxle. I'd probably just cut off the trans housing, weld on a plate and go to it. You have to be kind of careful with true swing axles though, the outer wheel in a turn tends to turn under. There were aftermarket devices to take care of that though.
Detroit is using solid axle housings I expect to widen their profit margin. The vehicles are fairly heavy too, so unsprung weight not that big a proportion of total.</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: Peter Brow (IP Logged)
Date: July 15, 2003 01:33AM
<HTML>Hi Terry,
Yes, swing axles have some cornering problems. Same problem that killed the Corvair (with help from Ralph Nader, who didn't seem to notice the identical system in the more-numerous VWs).
In 1968 VW started offering double-jointed axles, at first only an option with the curious "Automatic Stickshift" transaxle (which I have on my '69 daily driver). The double-jointed system, which became standard in 1969, is an order of magnitude better. It has constant velocity joints (CVJs) at both ends of the half-axle shafts. My '69 parts car has this type of final drive/suspension; that is the one I'd use if I were going to go IRS. It is very durable and popular for use in dune buggies, kit cars, and other custom vehicles. The swing axle system is on a '64 Bug chassis (an ex-Baja 1000 vehicle) which I bought for an abortive (and IRS) steam car attempt in the late 1980s.
I think you touched on one advantage of solid axles: they are cheaper. For example, performance VW CVJ's are something like $70 each, and there's 4 per vehicle. There is no equivalent expense in a solid axle. Who knows what the new irs stuff costs?
Unsprung weight seems to be the main problem with solid axles. I am working hard to keep the weight down, consistent with safety and durability. Just being IRS doesn't mean that a suspension is automatically better in this department. I remember driving both a 1988 Honda Accord (irs) and a 1966 Dodge Dart (solid axle) over the same, oft-traveled and particularly nasty high-speed dip/curve in the road. The mag-wheeled Honda had some very disturbing wheel hop; the Dodge with clunky stock steel rims kept its rear wheels right on the road. Vehicle weight and speed were about the same.
Eventually I learned to take that dip slower in the Honda. I never slowed down for it in the Bug. It just glided over with a slight pitching motion. It was always funny to watch obnoxious tailgaters ("Hurry up, you slow-poke Volkswagen!") hopping their hot new cars out of that unexpected dip and then panic-stomping their brakes as I disappeared around the bend. I'd obligingly accelerate for these bumper-kissing speed demons as we approached the dip. Then, BOING-SCREECH! Buh-bye. They thought their car could keep up! And people think Old Bugs are no fun. :) Alas, the City finally fixed that dip a few years ago.
But I have located some nasty new road dips. :)
I couldn't tell any difference in road adhesion between the Dodge and my Bug, which has about the lowest unsprung weight possible, even in really hairy driving and Starsky and Hutch/Dukes of Hazzard type cornering on really lousy roads. And the Dodge would run a lot faster than the Bug, and rode much smoother than either the Honda or the Bug. All this with a solid rear axle.
So I think that the quality of the design and materials are as important as the type of suspension. For the most part, 1960s Dodges were really well-engineered for the type of equipment they had. 1980s Hondas, hm.
Not sure, but I suspect that effective unsprung weight with the composite/chromoly axle I am designing may actually be lower than many IRS cars with heavy steel A-arms, steel multilinks, etc.. Also, during engine/axle mockup motion tests, I noticed that the engine barely moves at all, even under full suspension travel. Especially at the cylinder end, which is where most of the weight will be in my design. This might not be such a bad "beginner design" after all.
But only road testing will tell for sure.
Peter</HTML>
Yes, swing axles have some cornering problems. Same problem that killed the Corvair (with help from Ralph Nader, who didn't seem to notice the identical system in the more-numerous VWs).
In 1968 VW started offering double-jointed axles, at first only an option with the curious "Automatic Stickshift" transaxle (which I have on my '69 daily driver). The double-jointed system, which became standard in 1969, is an order of magnitude better. It has constant velocity joints (CVJs) at both ends of the half-axle shafts. My '69 parts car has this type of final drive/suspension; that is the one I'd use if I were going to go IRS. It is very durable and popular for use in dune buggies, kit cars, and other custom vehicles. The swing axle system is on a '64 Bug chassis (an ex-Baja 1000 vehicle) which I bought for an abortive (and IRS) steam car attempt in the late 1980s.
I think you touched on one advantage of solid axles: they are cheaper. For example, performance VW CVJ's are something like $70 each, and there's 4 per vehicle. There is no equivalent expense in a solid axle. Who knows what the new irs stuff costs?
Unsprung weight seems to be the main problem with solid axles. I am working hard to keep the weight down, consistent with safety and durability. Just being IRS doesn't mean that a suspension is automatically better in this department. I remember driving both a 1988 Honda Accord (irs) and a 1966 Dodge Dart (solid axle) over the same, oft-traveled and particularly nasty high-speed dip/curve in the road. The mag-wheeled Honda had some very disturbing wheel hop; the Dodge with clunky stock steel rims kept its rear wheels right on the road. Vehicle weight and speed were about the same.
Eventually I learned to take that dip slower in the Honda. I never slowed down for it in the Bug. It just glided over with a slight pitching motion. It was always funny to watch obnoxious tailgaters ("Hurry up, you slow-poke Volkswagen!") hopping their hot new cars out of that unexpected dip and then panic-stomping their brakes as I disappeared around the bend. I'd obligingly accelerate for these bumper-kissing speed demons as we approached the dip. Then, BOING-SCREECH! Buh-bye. They thought their car could keep up! And people think Old Bugs are no fun. :) Alas, the City finally fixed that dip a few years ago.
But I have located some nasty new road dips. :)
I couldn't tell any difference in road adhesion between the Dodge and my Bug, which has about the lowest unsprung weight possible, even in really hairy driving and Starsky and Hutch/Dukes of Hazzard type cornering on really lousy roads. And the Dodge would run a lot faster than the Bug, and rode much smoother than either the Honda or the Bug. All this with a solid rear axle.
So I think that the quality of the design and materials are as important as the type of suspension. For the most part, 1960s Dodges were really well-engineered for the type of equipment they had. 1980s Hondas, hm.
Not sure, but I suspect that effective unsprung weight with the composite/chromoly axle I am designing may actually be lower than many IRS cars with heavy steel A-arms, steel multilinks, etc.. Also, during engine/axle mockup motion tests, I noticed that the engine barely moves at all, even under full suspension travel. Especially at the cylinder end, which is where most of the weight will be in my design. This might not be such a bad "beginner design" after all.
But only road testing will tell for sure.
Peter</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: Mike Clark (IP Logged)
Date: July 16, 2003 09:06PM
<HTML>How about a DeDion rear axle - engine and diff frame mounted with half shafts having two U/Js each, wheels and suspension joined from side to side by a solid axle tube curved out to the back to clear the diff. Look at the front end of the front wheel drive Miller racing cars. If you could find it in a junkyard the complete backend off the British P6 Rover 2000 of the late 60's early 70's has everything you need. You could use leaf springs for simplicity.
Mike</HTML>
Mike</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: Peter Brow (IP Logged)
Date: July 17, 2003 09:09AM
<HTML>Hi Mike,
Now there's a classic suspension! This ought to be in production still. It is relatively simple, wheels are solidly aligned and located, and unsprung weight is the same or less than many of today's complex IRS systems. DeDion suspension still needs CV joints, with their extra friction losses and expense, but it solves several other problems, and I will consider it, for future projects if not this one.
For some reason, this reminds me of another suspension system I have always found interesting, the Citroen 2CV. Front and rear suspension are interlinked such that when the front goes over a bump, a linkage extends the rear wheels downward (jacking up the rear), and vice-versa, negating most vehicle pitch over bumps. Haven't been in one yet, but have read that it gives a surprisingly good ride for such a cheap car. A similar principle was used in some British cars, elaborated to include a hydro-pneumatic cross-linkage to also control body roll over bumps, but I can't remember which makes/models now. Something like this would really compliment a good steam car's smooth running.
Peter</HTML>
Now there's a classic suspension! This ought to be in production still. It is relatively simple, wheels are solidly aligned and located, and unsprung weight is the same or less than many of today's complex IRS systems. DeDion suspension still needs CV joints, with their extra friction losses and expense, but it solves several other problems, and I will consider it, for future projects if not this one.
For some reason, this reminds me of another suspension system I have always found interesting, the Citroen 2CV. Front and rear suspension are interlinked such that when the front goes over a bump, a linkage extends the rear wheels downward (jacking up the rear), and vice-versa, negating most vehicle pitch over bumps. Haven't been in one yet, but have read that it gives a surprisingly good ride for such a cheap car. A similar principle was used in some British cars, elaborated to include a hydro-pneumatic cross-linkage to also control body roll over bumps, but I can't remember which makes/models now. Something like this would really compliment a good steam car's smooth running.
Peter</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: Jim Crank (IP Logged)
Date: July 17, 2003 12:22PM
<HTML>Peter,
Worry more about the geometry of suspension systems and less about unsprung weight. It's the ratio you need to consider, sprung to unsprung weight.
The 2-CV Citroen used a knock kneeded interconnected version of that Dubonnet suspension that the 37 Chevy used. Hardly one that was inspiring when cornering hard!
The British car you are trying to recall was, among others by the same maker, the MG 1100 two door sedan. It used that Hydrolast suspension system that combined rubber suspension with hydraulic coupling of the two right side wheels, with the same thing on the left side, the two sides were not interconnected. I don't think the units are even available now.
Back when amateur road racing was fun, I devised a simple pressurizing system for a friend of mine that was racing one, that had a little lever valve system that would pump up the left side when going around a right hand turn and the opposite side when going around a left hand turn. The car cornered absolutely flat, and we never got caught by the tech inspectors. Great fun, creative cheating was a high art in those days in the production classes of SCCA racing.
The idea of a successful suspension system is to keep the wheels perphendicular to the road under all circumstances, with the tire patch always in maximum contact. Go find a wrecked Miata and take the whole front and rear suspensions and use that. Very well designed.
Been there so many times with race cars. Lots of good suspension system analysis in books from Classic Motor Books, get one and read it.
The suspension system is the very least of your worries.
Jim</HTML>
Worry more about the geometry of suspension systems and less about unsprung weight. It's the ratio you need to consider, sprung to unsprung weight.
The 2-CV Citroen used a knock kneeded interconnected version of that Dubonnet suspension that the 37 Chevy used. Hardly one that was inspiring when cornering hard!
The British car you are trying to recall was, among others by the same maker, the MG 1100 two door sedan. It used that Hydrolast suspension system that combined rubber suspension with hydraulic coupling of the two right side wheels, with the same thing on the left side, the two sides were not interconnected. I don't think the units are even available now.
Back when amateur road racing was fun, I devised a simple pressurizing system for a friend of mine that was racing one, that had a little lever valve system that would pump up the left side when going around a right hand turn and the opposite side when going around a left hand turn. The car cornered absolutely flat, and we never got caught by the tech inspectors. Great fun, creative cheating was a high art in those days in the production classes of SCCA racing.
The idea of a successful suspension system is to keep the wheels perphendicular to the road under all circumstances, with the tire patch always in maximum contact. Go find a wrecked Miata and take the whole front and rear suspensions and use that. Very well designed.
Been there so many times with race cars. Lots of good suspension system analysis in books from Classic Motor Books, get one and read it.
The suspension system is the very least of your worries.
Jim</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: jim reed (IP Logged)
Date: July 18, 2003 01:11AM
<HTML>Most of us old hot rodders use Ford 9" rear axles if we go with a non independent system. They are cheap, tough as nails, come in avariety of ratios and are plentiful. Weigh in at 221 lbs. The Lincoln version has disc brakes. Some can be found with a locker diff. They usually go for $300-500 For irs most use the Jag rear end. It is a self contained sub unit complete with inboard disc brakes and twin shocks per side. It is also a very handsome looking unit. It is easier to mount than a Ford axle if your building your own chassis. They are also very plentiful having been used in Jag sedans as well as sports cars for decades. Down here in FL the Ford non locker axles can be found for between $50-150. I've never bought a Jag rear end but a guy up at the local junk yard quoted me $300 for one.
They are more limited on ratios.
For a bolt in irs front end the 1989-93 Toyota pickup has a nice assembly. It uses torsion bars and rack and pinion steering. Like the Jag rear end it is a self contained sub assembly requiring only mounts for the aft ends of the bars besides the primary chassis mounting points. You could also use the Jag torsion bar front end but I can't remember if it is a sub assembly. Of course their is also the old VW front end standby which is also torsion bar.
Regards, Jim Reed</HTML>
They are more limited on ratios.
For a bolt in irs front end the 1989-93 Toyota pickup has a nice assembly. It uses torsion bars and rack and pinion steering. Like the Jag rear end it is a self contained sub assembly requiring only mounts for the aft ends of the bars besides the primary chassis mounting points. You could also use the Jag torsion bar front end but I can't remember if it is a sub assembly. Of course their is also the old VW front end standby which is also torsion bar.
Regards, Jim Reed</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: Peter Brow (IP Logged)
Date: July 18, 2003 10:39AM
<HTML>Hi Jim,
Thanks for the correction. Checked my suspension books, and yes, the British Leyland Hydragas & Hydrolastic springs used front-rear connection, not cross-connection. I was confusing it with an idea of my own (since discarded). Also thanks for the info on the Dubonnet system. With something like that, body C.G. has to be level with suspension pivots for level cornering -- or below it, if you want to "bank" into turns! But your hydragas mod takes care of that. The "lowriders", with their trick pneumatics, must be turning green with envy. At least one of us likes something about the Miata! And yes, suspensions are the least of my problems (and a bit off-topic for this forum, come to think of it).
Wish I could duplicate the "rides on rails" handling reported in some of the better 1920s sports cars (Stutz, etc) -- beam axles & leaf springs front and rear. And how 'bout those friction shocks!
Peter</HTML>
Thanks for the correction. Checked my suspension books, and yes, the British Leyland Hydragas & Hydrolastic springs used front-rear connection, not cross-connection. I was confusing it with an idea of my own (since discarded). Also thanks for the info on the Dubonnet system. With something like that, body C.G. has to be level with suspension pivots for level cornering -- or below it, if you want to "bank" into turns! But your hydragas mod takes care of that. The "lowriders", with their trick pneumatics, must be turning green with envy. At least one of us likes something about the Miata! And yes, suspensions are the least of my problems (and a bit off-topic for this forum, come to think of it).
Wish I could duplicate the "rides on rails" handling reported in some of the better 1920s sports cars (Stutz, etc) -- beam axles & leaf springs front and rear. And how 'bout those friction shocks!
Peter</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: Peter Brow (IP Logged)
Date: July 18, 2003 11:00AM
<HTML>Hi Jim,
Thanks. Yep, the old Ford 9", great bulletproof axles and another classic. A couple people have adapted these to Stanley engines, and similar axles to similar engines, just drill 4 holes for the frame rods and a few minor mods, and you're in like Flynn. But steel's too heavy for a really light roadster like I am planning. Gotta keep the weight down, especially with that engine hanging there.
I've seen a couple customs with Jag fronts & rears. Excellent equipment. Your mention of the Toyota with torsion bars reminds me of the '65 'Cuda I went across country in earlier this year, another great design -- bars run front to rear instead of side to side like the VW stuff I'm used to. I'm up to my eyeballs in Old VW junk and would have to be nuts to go with something more expensive or less available for independent suspension. Front will probably be VW (later type, ball joint) as I'm only halfway stuck in the stone age. Though I did briefly _consider_ a dropped T front axle ... maybe a Stutz front axle for the next car ... "rides on rails" ...
:)
Peter</HTML>
Thanks. Yep, the old Ford 9", great bulletproof axles and another classic. A couple people have adapted these to Stanley engines, and similar axles to similar engines, just drill 4 holes for the frame rods and a few minor mods, and you're in like Flynn. But steel's too heavy for a really light roadster like I am planning. Gotta keep the weight down, especially with that engine hanging there.
I've seen a couple customs with Jag fronts & rears. Excellent equipment. Your mention of the Toyota with torsion bars reminds me of the '65 'Cuda I went across country in earlier this year, another great design -- bars run front to rear instead of side to side like the VW stuff I'm used to. I'm up to my eyeballs in Old VW junk and would have to be nuts to go with something more expensive or less available for independent suspension. Front will probably be VW (later type, ball joint) as I'm only halfway stuck in the stone age. Though I did briefly _consider_ a dropped T front axle ... maybe a Stutz front axle for the next car ... "rides on rails" ...
:)
Peter</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: Jim Crank (IP Logged)
Date: July 18, 2003 12:38PM
<HTML>Peter,
Now, now, let's not say nasty things about Stutz. My Black Hawk speedster did corner very well for a 1928 car. The big thing about Stutz was their low center of gravity, thanks to that worm drive rear end. It was a lot lower than others of that era, especially my old R-R convertable. That one was way up there. Mu Stutz had hydraulic shocks, not Hartford friction, that was the older Bearcat.
Jim Reed gives good advice, the XK Jag rear end assembly, or for that matter, one from a late Corvette. At least they have the brakes on the outside and not buried with the differential unit. All easily found around here.
A VW suspension geometry is enough to give one the vapors, the worst ever.
Jim</HTML>
Now, now, let's not say nasty things about Stutz. My Black Hawk speedster did corner very well for a 1928 car. The big thing about Stutz was their low center of gravity, thanks to that worm drive rear end. It was a lot lower than others of that era, especially my old R-R convertable. That one was way up there. Mu Stutz had hydraulic shocks, not Hartford friction, that was the older Bearcat.
Jim Reed gives good advice, the XK Jag rear end assembly, or for that matter, one from a late Corvette. At least they have the brakes on the outside and not buried with the differential unit. All easily found around here.
A VW suspension geometry is enough to give one the vapors, the worst ever.
Jim</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: EARL C. LEAVEY (IP Logged)
Date: July 19, 2003 04:38PM
<HTML>HI! JIM, I THOUGHT YOU WOULD LIKE THESE LINKS TO XK120 REPLICARS. THIS CAR COULD MAKE A GREAT STEAMER. [www.kitcar.com] [www.specialtyauto.com];
Re: Solid Axle vs. Independent Suspension
Posted by: EARL C. LEAVEY (IP Logged)
Date: July 19, 2003 04:41PM
<HTML>LINKS: < [www.kitcar.com]; [www.specialtyauto.com];
Re: Solid Axle vs. Independent Suspension
Posted by: EARL C. LEAVEY (IP Logged)
Date: July 19, 2003 04:46PM
<HTML>[www.specialtyauto.com] [www.kitcar.com];
Re: Solid Axle vs. Independent Suspension
Posted by: Jim Crank (IP Logged)
Date: July 20, 2003 10:10AM
<HTML>Earl,
No where enough room in an XK 120 Jag. The Series 3 V-12 can do it; but a C-4 Corvette is even better, more room and lighter by some 330 pounds.
What I want is a mid engined kit car, like the Ford GT-40, that is being made to take the Jag V-12 engine. So far I have not found it.
Jim</HTML>
No where enough room in an XK 120 Jag. The Series 3 V-12 can do it; but a C-4 Corvette is even better, more room and lighter by some 330 pounds.
What I want is a mid engined kit car, like the Ford GT-40, that is being made to take the Jag V-12 engine. So far I have not found it.
Jim</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: David K Nergaard (IP Logged)
Date: July 20, 2003 12:52PM
<HTML>With the De Dion axle, ordinary universal joints work quite well. It is not necessary to use constant velocity joints. "Buck" Boudeman has used Jaguar differentials in a De Dion cofiguration with considerable success.
The real issue is not so much the axle weight in the classic Stanley configuration as the combined axle-engine weight. I think a De Dion drive is the way to go with any experimental engine, which is likely to be rather heavy.</HTML>
The real issue is not so much the axle weight in the classic Stanley configuration as the combined axle-engine weight. I think a De Dion drive is the way to go with any experimental engine, which is likely to be rather heavy.</HTML>
Re: Solid Axle vs. CHAIN DRIVE
Posted by: C Benson (IP Logged)
Date: July 20, 2003 09:07PM
<HTML>Has anyone ponderd the excelent handeling of the CHAIN DRIVE cars of 1904--1912,,,an that the Panhard had camberd wheels front an rear,, [later used by Mercedes on a live ax'l in '23 ] [2 ring gears] Cheers Ben p/s I still dont like Juce brakes,,,haha cb</HTML>
Re: Solid Axle vs. CHAIN DRIVE
Posted by: Peter Heid (IP Logged)
Date: July 21, 2003 02:48PM
<HTML>Make mine a belt drive. Today's cog belts are very strong, durable and transfer great amounts of power with very little weight. The cogs can even be of light alloys for a huge savings in weight and rotating mass.</HTML>
Re: Solid Axle vs. CHAIN DRIVE & Belts
Posted by: Peter Brow (IP Logged)
Date: July 22, 2003 03:12AM
<HTML>Hi Peter H,
Cogs can even be fiber-reinforced plastic, like carbon/epoxy, for even lighter weight. Toothed belts are quieter than chains (unless you want 3 chains in a "silent chain" layout), need no lube, easy to change out, and are even used in high-torque motorcycle driveline applications. Not sure about mechanical efficiency (oh boy, there I go again).
Some early trucks mounted a solid axle with differential/shafts rigidly to the vehicle frame, with a drive chain to each rear wheel. Do the same thing with toothed belts, and you've got practically zilch unsprung driveline component weight, with no CV or U-joints needed.
Then put the disk brakes in aircooling ducts on the ends of the frame-mounted axle, and even less unsprung weight (dangerous if a belt shreds though). While we're at it, add some carbon/epoxy rims and maybe hubless wheels ... woops, pardon my science fiction ... how about adding carbon/epoxy Morgan-front-suspension type rear suspension, with 2 booted slide-columns/wheel, two-axis computer-tilted for perfect camber/caster ... next stop, airless ultralow-profile tires made of woven rubber-coated amorphous boron fibers with aerogel cores ... ain't gonna have any unsprung weight left at this rate ... careful when you change a tire ... demounted wheel assemblies blowing away in a light breeze ...
"And it's powered by STEAM!"
Peter B</HTML>
Cogs can even be fiber-reinforced plastic, like carbon/epoxy, for even lighter weight. Toothed belts are quieter than chains (unless you want 3 chains in a "silent chain" layout), need no lube, easy to change out, and are even used in high-torque motorcycle driveline applications. Not sure about mechanical efficiency (oh boy, there I go again).
Some early trucks mounted a solid axle with differential/shafts rigidly to the vehicle frame, with a drive chain to each rear wheel. Do the same thing with toothed belts, and you've got practically zilch unsprung driveline component weight, with no CV or U-joints needed.
Then put the disk brakes in aircooling ducts on the ends of the frame-mounted axle, and even less unsprung weight (dangerous if a belt shreds though). While we're at it, add some carbon/epoxy rims and maybe hubless wheels ... woops, pardon my science fiction ... how about adding carbon/epoxy Morgan-front-suspension type rear suspension, with 2 booted slide-columns/wheel, two-axis computer-tilted for perfect camber/caster ... next stop, airless ultralow-profile tires made of woven rubber-coated amorphous boron fibers with aerogel cores ... ain't gonna have any unsprung weight left at this rate ... careful when you change a tire ... demounted wheel assemblies blowing away in a light breeze ...
"And it's powered by STEAM!"
Peter B</HTML>
Re: Solid Axle vs. CHAIN DRIVE
Posted by: jim reed (IP Logged)
Date: July 23, 2003 02:49AM
<HTML>I race laydown type enduro karts with 30 hp. Everyone uses toothed belt drive. They are bullet proof, light, quiet and super clean comparred to chain drive.</HTML>
Re: Solid Axle vs. CHAIN DRIVE & Belts
Posted by: Howard Rnadall (IP Logged)
Date: July 23, 2003 10:36AM
<HTML>Peter
If you really want to keep the fantasy going why not "And it's all powered by WATER"?
This is the belief of many people when they first approach my Stanley at a show or tour. I hate to disappoint them with the burner/ boiler truth.</HTML>
If you really want to keep the fantasy going why not "And it's all powered by WATER"?
This is the belief of many people when they first approach my Stanley at a show or tour. I hate to disappoint them with the burner/ boiler truth.</HTML>
Re: Solid Axle vs. CHAIN DRIVE & Belts
Posted by: Peter Brow (IP Logged)
Date: July 24, 2003 09:54AM
<HTML>Hi Howard,
Yep, I run into that all the time too when I mention my steam car project. I like to tell them, "yes the engine runs on vaporized water, which needs refilling now and then, and it burns gasoline to supply energy to turn the water into steam". Then they can say, "of course, I knew that it must need some kind of fuel" (though many don't seem to know, but I act like they already do and I'm simply anticipating their next question, "which fuel?", rather than correcting them). Then I change the subject quickly to multifuel capability, clean burning, performance advantages, etc, as if the need for fuel is an obvious point that barely needs mentioning.
I have found this more agreeable than "no, it doesn't run on water, there's no useable energy in water, it runs on fuel", physics lesson, etc -- which is more likely to bring up dumb stories about the suppressed-technology cars they heard about that run entirely on water, which provokes me into debunking & debate.
Peter</HTML>
Yep, I run into that all the time too when I mention my steam car project. I like to tell them, "yes the engine runs on vaporized water, which needs refilling now and then, and it burns gasoline to supply energy to turn the water into steam". Then they can say, "of course, I knew that it must need some kind of fuel" (though many don't seem to know, but I act like they already do and I'm simply anticipating their next question, "which fuel?", rather than correcting them). Then I change the subject quickly to multifuel capability, clean burning, performance advantages, etc, as if the need for fuel is an obvious point that barely needs mentioning.
I have found this more agreeable than "no, it doesn't run on water, there's no useable energy in water, it runs on fuel", physics lesson, etc -- which is more likely to bring up dumb stories about the suppressed-technology cars they heard about that run entirely on water, which provokes me into debunking & debate.
Peter</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: Mark Stacey (IP Logged)
Date: July 24, 2003 06:09PM
<HTML>I'm interested in running through the problems in bolting up a 2 cylinder engine to an XJ6 IRS assembley as this is probably what I will do in the next year or two.
The sequence as I've thought it through is the pinion shaft and associated gubbins need to be removed, the crownwheel replaced with a spur gear, next looking down on the diff head the diff assembly is rotated through 180 degrees.
This is so the carrier for the diff is facing the back of the car and the face that had the oil cover faces forward ready to mount the engine in the same orientation as a Stanley or Doble.
An adaptor plate is milled to bolt to the engine and allign the engines spur gear to the diff spur gear.
This assumes that the XJ6 rubber mounted cage has been discarded and the diff is solid mounted via the 4 bolts in the top of the diff and the bottom wish bone piviots.
Peter have you weighed the bits you will have to retain for your composite rear axle ie differential gear and suports, axle shafts, brakes etc and compared that to the total diff weight? I think the weight /cost / time equation will be in favour of modifying a stock Ford 9" diff.
Cheers
Mark Stacey</HTML>
The sequence as I've thought it through is the pinion shaft and associated gubbins need to be removed, the crownwheel replaced with a spur gear, next looking down on the diff head the diff assembly is rotated through 180 degrees.
This is so the carrier for the diff is facing the back of the car and the face that had the oil cover faces forward ready to mount the engine in the same orientation as a Stanley or Doble.
An adaptor plate is milled to bolt to the engine and allign the engines spur gear to the diff spur gear.
This assumes that the XJ6 rubber mounted cage has been discarded and the diff is solid mounted via the 4 bolts in the top of the diff and the bottom wish bone piviots.
Peter have you weighed the bits you will have to retain for your composite rear axle ie differential gear and suports, axle shafts, brakes etc and compared that to the total diff weight? I think the weight /cost / time equation will be in favour of modifying a stock Ford 9" diff.
Cheers
Mark Stacey</HTML>
Re: Solid Axle vs. Independent Suspension
Posted by: Peter Brow (IP Logged)
Date: July 25, 2003 09:05AM
<HTML>Hi Mark,
Don't have a complete weight schedule yet. Both the innards and the housing should weigh a lot less than a Ford 9" rear, including the differential, Accurate positioning jig for axle innards during FRP layup will be a big part of the workload. Cores and outer mold should be a piece of cake, for me anyway; definitely not recommended for those who haven't worked with reinforced plastics before (get some experience with other structural FRP projects first, it's cheap/easy to learn/do, but takes time to get the hang, main tools are paper cups, measuring cups, brushes, scissors, disposeable gloves, and wood mix stix).
Drilling housing and making adaptor plates for standard rears (axle or IRS) is reportedly a lot of work; the labor difference vis a vis custom axle doesn't look too extreme. Some guys (incl I think Warriner and McNeir) reportedly welded-in reinforcements around the rod holes. McNeir used a Pinto axle (9"?), and Warriner used ancient Dodge as I recall.
Also, not sure if there are interference problems with diff, bearings, etc in a Ford 9. The pumpkin looks pretty big on those, and Stanley 7 has 5.75" frame rod spacing; 4.75" in my engine. Will the Ford 9 diff & its bearings fit inside? Rods thru axle looks lighter/beefier than adaptor plate; for IRS, plate should be fine. All kinds of questions with conversions, which are avoided with scratch design.
If I were going with a steel housing, there is a hot rod shop that cuts/welds beefy custom housings from plate & tube, your specs for guts & suspension mounts, for something like US$400. They'd have no problem adding frame rod holes and other needed features.
Diff should be much lighter than a Ford 9, but this also has a downside: strength. In high torque conditions, VW diffs can strip the spider and/or side gears. However, there is a drop-in "Super Diff" available with twice the number of spider gears and minimal weight penalty, and these take incredible loads in performance driving that would make Dr. Porsche (in his pre-sports-car days) flip. Then again, the current diff already went through the Baja 1000 (think Paris-Dakar via Hell) with no apparent damage, and I'm not going to do much lead-footing with instant 700 lb ft or something on tap, modern hardened/alloy drive gears or no. "I may be nuts, but I'm not crazy", or like that.
Keep us posted on your progress with the Jag rear/classic engine rig. I for one am very interested, and I doubt I'm alone on that.
Peter</HTML>
Don't have a complete weight schedule yet. Both the innards and the housing should weigh a lot less than a Ford 9" rear, including the differential, Accurate positioning jig for axle innards during FRP layup will be a big part of the workload. Cores and outer mold should be a piece of cake, for me anyway; definitely not recommended for those who haven't worked with reinforced plastics before (get some experience with other structural FRP projects first, it's cheap/easy to learn/do, but takes time to get the hang, main tools are paper cups, measuring cups, brushes, scissors, disposeable gloves, and wood mix stix).
Drilling housing and making adaptor plates for standard rears (axle or IRS) is reportedly a lot of work; the labor difference vis a vis custom axle doesn't look too extreme. Some guys (incl I think Warriner and McNeir) reportedly welded-in reinforcements around the rod holes. McNeir used a Pinto axle (9"?), and Warriner used ancient Dodge as I recall.
Also, not sure if there are interference problems with diff, bearings, etc in a Ford 9. The pumpkin looks pretty big on those, and Stanley 7 has 5.75" frame rod spacing; 4.75" in my engine. Will the Ford 9 diff & its bearings fit inside? Rods thru axle looks lighter/beefier than adaptor plate; for IRS, plate should be fine. All kinds of questions with conversions, which are avoided with scratch design.
If I were going with a steel housing, there is a hot rod shop that cuts/welds beefy custom housings from plate & tube, your specs for guts & suspension mounts, for something like US$400. They'd have no problem adding frame rod holes and other needed features.
Diff should be much lighter than a Ford 9, but this also has a downside: strength. In high torque conditions, VW diffs can strip the spider and/or side gears. However, there is a drop-in "Super Diff" available with twice the number of spider gears and minimal weight penalty, and these take incredible loads in performance driving that would make Dr. Porsche (in his pre-sports-car days) flip. Then again, the current diff already went through the Baja 1000 (think Paris-Dakar via Hell) with no apparent damage, and I'm not going to do much lead-footing with instant 700 lb ft or something on tap, modern hardened/alloy drive gears or no. "I may be nuts, but I'm not crazy", or like that.
Keep us posted on your progress with the Jag rear/classic engine rig. I for one am very interested, and I doubt I'm alone on that.
Peter</HTML>
Re: Solid Axle vs. CHAIN DRIVE & Belts
Posted by: Peter Brow (IP Logged)
Date: September 19, 2003 08:06AM
<HTML>Reviewing this thread: In my flip-sounding speculative post, I wasn't kidding about anything except the hubless wheels and aerogel tires. The brainstorming just got a bit out of hand. I wanted to add that a car was actually built with hubless wheels, a well-designed experimental vehicle in Italy(?), in the 1990s. Drive was via an internal ring gear in the wheel rim. Probably not good for a steam car, considering the inherently high gear ratio. But it did have extremely low unsprung weight. Aerogel tires, no. The rest is doable, though, and is the sort of stuff I think sports cars will have in 20-30 years. Too advanced for me to try at present. Toothed belt drive is already a good idea. It is now used in motorcycles, and it is probably only a matter of time before some manufacturer uses it in a car, if it hasn't been tried already. Eventually it might replace today's drivetrains.
Jim: While I'm at it, yes, VW suspension has the worst geometry ever. Well, there is the Trabant to consider. "Rides on rails" was intended as a compliment to Stutz, and friction shocks worked and might be re-inventable (considerable improvement needed). Not to mention mechanical brakes -- I start thinking like Ben about juice brakes every time I have to work on them. With hefty cable-tubes, self-adjusters, and some carefully-designed equalizing levers in a sealed oil-bath box ... but these are strictly back-burner ideas for now.
I think that lots of further-developable ideas get dumped for temporary business & perception reasons rather than inherent technical reasons. With improved design, some may turn out better than the machines which were preferred. Steam cars may be one example.
Having driven one, the Miata earns my grudging admiration. The suspension is superb, I just don't like the look of the car. Also it has the wrong kind of engine. It's not steam. :)
Peter</HTML>
Jim: While I'm at it, yes, VW suspension has the worst geometry ever. Well, there is the Trabant to consider. "Rides on rails" was intended as a compliment to Stutz, and friction shocks worked and might be re-inventable (considerable improvement needed). Not to mention mechanical brakes -- I start thinking like Ben about juice brakes every time I have to work on them. With hefty cable-tubes, self-adjusters, and some carefully-designed equalizing levers in a sealed oil-bath box ... but these are strictly back-burner ideas for now.
I think that lots of further-developable ideas get dumped for temporary business & perception reasons rather than inherent technical reasons. With improved design, some may turn out better than the machines which were preferred. Steam cars may be one example.
Having driven one, the Miata earns my grudging admiration. The suspension is superb, I just don't like the look of the car. Also it has the wrong kind of engine. It's not steam. :)
Peter</HTML>
Sorry, only registered users may post in this forum.