who makes caster shims and how do they work, s far as how do they change the angle on the upper a arm. bill
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who makes caster shims and how do they work, s far as how do they change the angle on the upper a arm. bill
http://www.thesamba.com/vw/forum/search.php?search_keywords=caster+shims&search_terms=all&search_author=&search_forum=-1&search_time=0&search_fields=all&search_cat=1&sort_by=0&sort_dir=DESC&show_results=topics&return_chars=200
CIP sells em cheap.
CIP sells em cheap.
Caster shims are basically washers. By installing them in the upper 2 bolts that hold the front beam to the tunnel, you decrease caster, If you install them in the lower holes, you effectively increase caster. The more caster you have, the straighter the car drives and more force seems to be applied during self centering after a turn.
Normal is 3 to 4 degree's but I like 6 as it gives you a very positive feel when driving.
Normal is 3 to 4 degree's but I like 6 as it gives you a very positive feel when driving.
These are the ones I've used. One on each side made a world of difference.
http://www2.cip1.com/ProductDetails.asp?ProductCode=ACC%2DC10%2D4190
~WB
http://www2.cip1.com/ProductDetails.asp?ProductCode=ACC%2DC10%2D4190
~WB
And if you have a lowered front beam (via adjusters) you WILL need caster shims, and don't leave home without them!
Regardless of what method you use to lower the front of the car, it seems to me that whether or not you need caster shims depends on the angle of the bottom of the car.
If you lower the front and not the back, you are changing the caster angle of the front wheels. Then you would need caster shims.
If you lower the back too, keeping the angle between the bottom of the car and the ground unchanged, it seems like you would not need caster shims.
I don't see where it would make any difference if you lower the front with adjusters on the beam or lowering spindles.
If you lower the front and not the back, you are changing the caster angle of the front wheels. Then you would need caster shims.
If you lower the back too, keeping the angle between the bottom of the car and the ground unchanged, it seems like you would not need caster shims.
I don't see where it would make any difference if you lower the front with adjusters on the beam or lowering spindles.
Ok guys here's the real deal with caster shims.
No matter if you lower the front,back, or both caster shims are a big help. The stock VW suspension was designed around a much longer wheel base, a heavier car, and a slower car. Lets lok at each of thease differences.
Longer wheel base: When the distance between the wheels is shortend the cars reaction to steering inputs speeds up thus by increasing caster you'll slow the steering back down. For example look at a motorcycle, the more angle in the steering tube the slower the steering but too much and you'll have a chopper that won't turn.
Heavier car: A heavier car will compress the suspension more in a turn then a lighter car. The lighter car will actualy have a retarded feeling going into a turn since it will take longer to compress and acheive the same angle gain as the heavier car.
Slower car: The quickness of the steering (caster) is also design around the overall speed of the car. Lets face it were not in the 60/70's anymore and our freeway speed is greater. All of BMW's M class cars start out life as a normal 3 or 5 series. One of the first things they do is add more caster to the front suspension by using a different suspension mounting point.
So it doesn't matter how high or low your vehicle is it will help out adding caster shims.
my .02 cents
No matter if you lower the front,back, or both caster shims are a big help. The stock VW suspension was designed around a much longer wheel base, a heavier car, and a slower car. Lets lok at each of thease differences.
Longer wheel base: When the distance between the wheels is shortend the cars reaction to steering inputs speeds up thus by increasing caster you'll slow the steering back down. For example look at a motorcycle, the more angle in the steering tube the slower the steering but too much and you'll have a chopper that won't turn.
Heavier car: A heavier car will compress the suspension more in a turn then a lighter car. The lighter car will actualy have a retarded feeling going into a turn since it will take longer to compress and acheive the same angle gain as the heavier car.
Slower car: The quickness of the steering (caster) is also design around the overall speed of the car. Lets face it were not in the 60/70's anymore and our freeway speed is greater. All of BMW's M class cars start out life as a normal 3 or 5 series. One of the first things they do is add more caster to the front suspension by using a different suspension mounting point.
So it doesn't matter how high or low your vehicle is it will help out adding caster shims.
my .02 cents
OK, I am starting to see that there may be some benefit to "adding" caster even if I don't need to "restore" caster because I lowered the back too.
Now I have some new concerns. If I rotate the beam I am moving things like the bumper brackets and the body mount that attaches to the top of the beam.
Now I have some new concerns. If I rotate the beam I am moving things like the bumper brackets and the body mount that attaches to the top of the beam.
Adding caster shims to the lower tube is only adding possibly 3 degrees. The rubber bushings between the body and beam will absorb that much difference, the repositioning of the front bumper won't be at all noticeable.
Rotating the beam with regards to an adjustable beam is just slang for rotating the torsion leaves within the beam.
Either way, no problems. I really like the extra few degrees of caster that the shims provide. Not noticeable around town and a real feeling of stability on the highway.
A bit of caution though, handling improvements can become an addition with a VW based car. The basic pan just responds SO well to every little "trick" that you don't want to stop. Shims, sway bars, urethane, shocks, torsion bar adjustment, camber compensator, brakes, light wheels, sticky tires. Any of these will make a big difference, all of them will make you want to install a potty chair in the bottom driver's seat cushion 'cause you'll never want to get out of the car. It just becomes THAT much a part of you when driving. The responsiveness is staggering, the fun-factor is off the scale.
Rotating the beam with regards to an adjustable beam is just slang for rotating the torsion leaves within the beam.
Either way, no problems. I really like the extra few degrees of caster that the shims provide. Not noticeable around town and a real feeling of stability on the highway.
A bit of caution though, handling improvements can become an addition with a VW based car. The basic pan just responds SO well to every little "trick" that you don't want to stop. Shims, sway bars, urethane, shocks, torsion bar adjustment, camber compensator, brakes, light wheels, sticky tires. Any of these will make a big difference, all of them will make you want to install a potty chair in the bottom driver's seat cushion 'cause you'll never want to get out of the car. It just becomes THAT much a part of you when driving. The responsiveness is staggering, the fun-factor is off the scale.
In regards to anti-sway bars. The stiffer the front bar, the more understeer you'll have (In other words, the front tires will scrub across the pavement instead of turning the car.
The stiffer the rear bar, the more oversteer you'll have. (In other words, the back will want to swap with the front)
An adjustable bar, front an rear is the best but not always practical or available. If the back starts to over steer, you can move the vertical bar towards the end of the anti sway bar and thus soften the torsional effect of the bar and cause a little bit more body roll to make the tires stick better in a turn...
The stiffer the rear bar, the more oversteer you'll have. (In other words, the back will want to swap with the front)
An adjustable bar, front an rear is the best but not always practical or available. If the back starts to over steer, you can move the vertical bar towards the end of the anti sway bar and thus soften the torsional effect of the bar and cause a little bit more body roll to make the tires stick better in a turn...
Very true about sway bars, however I've been a Porsche club of America performance driving instructer for over 14 years and have yet to find a 356 that needed a rear sway bar due to the sort wheel base. I would recomend limiting strap for the back of all the swing axle cars after my up on two wheel experiance. The rear wheel tucked under in a hard turn and if I would not have known to turn in the dirrection of the down side, I would have been up-side down.... Not Good
Kevin,
What do you recommend the limiting straps be made from. I have a camber compensator cross bar in my swing axle and limiting straps based on shortened 3 inch wide ratchet-style hold down straps, like we use to secure the car to the trailer.
Think that these will do the job or is there too much stretch in the weave? Would the straps from a racing seat harness be a better bet? Or anything else to suggest?
Thanks !
TC
What do you recommend the limiting straps be made from. I have a camber compensator cross bar in my swing axle and limiting straps based on shortened 3 inch wide ratchet-style hold down straps, like we use to secure the car to the trailer.
Think that these will do the job or is there too much stretch in the weave? Would the straps from a racing seat harness be a better bet? Or anything else to suggest?
Thanks !
TC
Kevin, absolutely agree. I fitted caster shims. The clown who did my wheel alignment said they shouldn't be needed as i run dropped spindles and took them out.
The car drives half as well without them. They're going back in.
The car drives half as well without them. They're going back in.
Kevin,
Are you saying rear sway bars are NOT needed? I just narrowed the rear track in my car to allow for more room within the wheel wells. However, I haven't really 'pushed' the car in any corners yet as there are still a few things that need to be sorted out. Having a narrower track in the rear, I would imagine, will increase the cars desire to oversteer, no? So if I put a rear sway bar back there I would be asking for even more oversteer? I have an IRS rear in my car.
Are you saying rear sway bars are NOT needed? I just narrowed the rear track in my car to allow for more room within the wheel wells. However, I haven't really 'pushed' the car in any corners yet as there are still a few things that need to be sorted out. Having a narrower track in the rear, I would imagine, will increase the cars desire to oversteer, no? So if I put a rear sway bar back there I would be asking for even more oversteer? I have an IRS rear in my car.
Yes, I'm saying with the wheel base on our little cars a rear sway bar is over kill and will cause more underster (push) because the wheel base is soo short and there is no wait on the frontend to start with. The wheel base is just too short, I raced a built 914 for over fifteen years and after framing the car up (stiffing the chassis) I had to remove the rear sway bar to get some body roll in the car so it would jook up in the corners. A sway bar not only effects the rear end of the car by not allowing body roll and causing overster, but also causes a certain amount of when trying to get into the corners.
Having the car too stiff is as bad as having it too loose. You want a little body roll in the car so that the inside wheel does not come off the ground when your in a turn, however with an open diff it would act like a govenor to slow you down since when the inside wheel comes off the ground the car will slow down.
I can go on for ever about car set up and making it handle as best as it can. I'll have my car on the skid pad once I finish the engine and I'll keep you guys up to date on the HOT SET-UP.....
Having the car too stiff is as bad as having it too loose. You want a little body roll in the car so that the inside wheel does not come off the ground when your in a turn, however with an open diff it would act like a govenor to slow you down since when the inside wheel comes off the ground the car will slow down.
I can go on for ever about car set up and making it handle as best as it can. I'll have my car on the skid pad once I finish the engine and I'll keep you guys up to date on the HOT SET-UP.....
"Yes, I'm saying with the wheel base on our little cars a rear sway bar is over kill and will cause more underster (push) because the wheel base is soo short and there is no wait on the frontend to start with."
I'm still a little confused - If I narrow the rear end that brings the wheels closer together and therefore the rear end will go out more easily which is oversteer, no?
But what you are saying is the shorter wheel base causes our cars to push, which makes sense to me. With narrowing up the rear on my car (by 3-4") I thought I would be inviting a greater likelyhood of the car's rear end letting go. Wouldn't decreasing sway in the rear compensate for that?
I'm still a little confused - If I narrow the rear end that brings the wheels closer together and therefore the rear end will go out more easily which is oversteer, no?
But what you are saying is the shorter wheel base causes our cars to push, which makes sense to me. With narrowing up the rear on my car (by 3-4") I thought I would be inviting a greater likelyhood of the car's rear end letting go. Wouldn't decreasing sway in the rear compensate for that?
Mickey,
Don't worry, don't take what you're readin' so seriously . . . I Googled Kevin and he doesn't exist.
You're arguing suspension balance points with, and taking advice from an eleven year old in second period Computer Science class with a second "window" open to the SCCA Tech Advice area.
I say, lock that narrowed rear end down as tight as can be, essentially turning your Speedster into a trike . . . . THEN watch that over steer in action.
You'll be doin' donuts just turning into your driveway ! !
Don't worry, don't take what you're readin' so seriously . . . I Googled Kevin and he doesn't exist.
You're arguing suspension balance points with, and taking advice from an eleven year old in second period Computer Science class with a second "window" open to the SCCA Tech Advice area.
I say, lock that narrowed rear end down as tight as can be, essentially turning your Speedster into a trike . . . . THEN watch that over steer in action.
You'll be doin' donuts just turning into your driveway ! !
"Oh, by the way you sound more like a child then I do on here."
Can you see my tongue sticking out at you from there . . . ?
Can you see my tongue sticking out at you from there . . . ?
Team Evil
Thanks forthe compliment, I wish I was that young again and if you can find a computor class that is open when I made my last post I'll stop posting and just listen to my teacher like a good boy.
If you look up Mendeola-motors.com you'll see some of the stuff I do, if you want to see my racing and car set up work take a look back at 2002 and before Porsche Club of America.
Here's some pictures of more recent projects I'm working on.
Oh, by the way you sound more like a child then I do on here.
Thanks forthe compliment, I wish I was that young again and if you can find a computor class that is open when I made my last post I'll stop posting and just listen to my teacher like a good boy.
If you look up Mendeola-motors.com you'll see some of the stuff I do, if you want to see my racing and car set up work take a look back at 2002 and before Porsche Club of America.
Here's some pictures of more recent projects I'm working on.
Oh, by the way you sound more like a child then I do on here.
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are you serious?????
"are you serious?????"
Why yes . . . yes I am.
I am, indeed, standing right here sticking my tongue out at you and wondering aloud if you can see me from where you are presently located.
That's exactly what I'm doing.
Why, can't you see me . . . ?
Why yes . . . yes I am.
I am, indeed, standing right here sticking my tongue out at you and wondering aloud if you can see me from where you are presently located.
That's exactly what I'm doing.
Why, can't you see me . . . ?
So why don't you tell us some things about suspension and what you've found to work as you seem to think I know nothing about suspsion even after me posting pictures of what I'm working, which I might add is completely designed in house.
Let's hear from the genuis about suspension???????
What, what you got girly-man??????
Let's hear from the genuis about suspension???????
What, what you got girly-man??????
are YOU serious?????
Smarten up. This is a light hearted bunch, we kid around. We don't call each other stupid "girly-man" names or demand to see credentials from each other.
We all already know pretty much what you know. Ask Gordon, ask Cory. We just like to banter about and share new stuff, and we fool around a LOT!
If you're not gonna smarten up, at least lighten up . . .
Smarten up. This is a light hearted bunch, we kid around. We don't call each other stupid "girly-man" names or demand to see credentials from each other.
We all already know pretty much what you know. Ask Gordon, ask Cory. We just like to banter about and share new stuff, and we fool around a LOT!
If you're not gonna smarten up, at least lighten up . . .
Hey, Kevin, TC's right. Not only is he not standing there sticking out his tongue, but I'd say he's probably pretty impressed by your work. He, like the rest of us, have a hard time taking our Volkswagens seriously.
You're a welcome addition.
You're a welcome addition.
And then for further info on older vW suspensions, what works and why, one can always look here:
http://www.aircooled.net/gnrlsite/resource/articles/handling.htm
http://www.aircooled.net/gnrlsite/resource/articles/handling.htm
Sorry, guys.
When I open up with tech stuff it is to help others out not make the same mistakes over and over. I take what I do seriously and as I've found on other sites there are a few dumb a$$es that like to think they know it all and like to step on someone like myself who is truley trying to help out with tried and true knowledge and I thought you where one of them. I don't like to waist my time typeing information in to a forum to have someone else say what I'm laying down is incorrect. I'm not a hard ass but when I feel some is throwing negitive crap out there I lose it.
Again I'm truely sorry for coming down soo hard. I'll remember next time to just reply "what ever" or "so" and just walk away.
I still think your a girly man because you don't have any pictures up here (don't ask me why)..... ;)
When I open up with tech stuff it is to help others out not make the same mistakes over and over. I take what I do seriously and as I've found on other sites there are a few dumb a$$es that like to think they know it all and like to step on someone like myself who is truley trying to help out with tried and true knowledge and I thought you where one of them. I don't like to waist my time typeing information in to a forum to have someone else say what I'm laying down is incorrect. I'm not a hard ass but when I feel some is throwing negitive crap out there I lose it.
Again I'm truely sorry for coming down soo hard. I'll remember next time to just reply "what ever" or "so" and just walk away.
I still think your a girly man because you don't have any pictures up here (don't ask me why)..... ;)
Kevin, I think it's inherent in the VW gene that we try to have a good time with what we're doing. Most of us started out as hobbyists with cars we didn't really understand; once we discover individually that we need to become mechanics for at least simple things, we do tend to come here for that knowledge -- or at least to get a series of opinions on what we think we're doing next.
Most of the guys who've been 'round here (so to speak) for longer than a few years have contributed scads of knowledge in one form or another, but from time to time, people pop up with some new thinking.
As Jim Ignacio likes to say, it's like having a conversation on your pal's back porch over a beer. Sometimes you act on the knowledge, other times you bookmark it.
I'd say that, even if nobody had a true or immediate use for your posts on caster shims, someone, probably working on their car quietly in their own garage late at night, will read it and take from it what you intended them to.
I worked with a guy for a year and a half on my car, effectively building my design from a drawing I made in Iraq. I won't let that guy near my car anymore for a number of reasons -- and even though I know an awful lot about mine, I'm still reading things that come up here because I won't draw on him for knowledge anymore.
Your advice is well-written and useful.
I'd suggest reading some of the posts from guys and gals who posted a few years back, and you'll see that there are a whole lot fewer pissing contests with this 'fun' change in direction than there used to be.
This is a great bunch here. And, maybe more importantly, it's a CAR club. We've all got these cars, and it seems like nobody else does. In addition to being a resource, we're also fun to cruise with.
My two cents.
Most of the guys who've been 'round here (so to speak) for longer than a few years have contributed scads of knowledge in one form or another, but from time to time, people pop up with some new thinking.
As Jim Ignacio likes to say, it's like having a conversation on your pal's back porch over a beer. Sometimes you act on the knowledge, other times you bookmark it.
I'd say that, even if nobody had a true or immediate use for your posts on caster shims, someone, probably working on their car quietly in their own garage late at night, will read it and take from it what you intended them to.
I worked with a guy for a year and a half on my car, effectively building my design from a drawing I made in Iraq. I won't let that guy near my car anymore for a number of reasons -- and even though I know an awful lot about mine, I'm still reading things that come up here because I won't draw on him for knowledge anymore.
Your advice is well-written and useful.
I'd suggest reading some of the posts from guys and gals who posted a few years back, and you'll see that there are a whole lot fewer pissing contests with this 'fun' change in direction than there used to be.
This is a great bunch here. And, maybe more importantly, it's a CAR club. We've all got these cars, and it seems like nobody else does. In addition to being a resource, we're also fun to cruise with.
My two cents.
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OK, that's all nice and everything but let's get back to ME!
What is the consensus on the rear sway bar? I understand the shortened wheel base promoting a push (understeer) and I believe a narrowed rear track will promote oversteer. With the way our cars are balanced will a rear sway bar help or hinder?
Being that the car is lighter up front by a considerable amount what can one do to improve front end grip? Lower it, sway bar, softer shocks, ect...?
Is there anyone out there that has a car similar to mine that has found a good set up?
What is the consensus on the rear sway bar? I understand the shortened wheel base promoting a push (understeer) and I believe a narrowed rear track will promote oversteer. With the way our cars are balanced will a rear sway bar help or hinder?
Being that the car is lighter up front by a considerable amount what can one do to improve front end grip? Lower it, sway bar, softer shocks, ect...?
Is there anyone out there that has a car similar to mine that has found a good set up?
Mickey, sorry for the digression.
I think you're going to find that wider tires will make a difference if the rubber compound is grippy. Without adding anything else to the underside of the rear, you'll be able to out-drive the oversteer by not getting off the throttle as you corner.
Out-driving understeer is not as easy to get right, so I'd say leaving it as it is (which you're going to be perfectly happy with) and putting your anti-sway efforts up front is a decent way to go.
Your own experience with the kart should be pretty good for oversteer understanding. The front is lighter than the back ... if you skip and hop on cornering, you plant your foot on the right-hand pedal and it smooths out your track. Your stiffer rear suspension will always try to keep both of the back tires on the ground.
In the Speedster, you'll just have to wait until you're in the apex of the turn. You should be able to feel the differences in that back road you took us down off of 202, wouldn't you think?
If you find that the car seems to get a bit of an arched back in a hard corner, maybe limiter-straps are an alternative. You can always take them off when you're done driving the car hard.
Here's one you might not have in your folder, Bro:
I think you're going to find that wider tires will make a difference if the rubber compound is grippy. Without adding anything else to the underside of the rear, you'll be able to out-drive the oversteer by not getting off the throttle as you corner.
Out-driving understeer is not as easy to get right, so I'd say leaving it as it is (which you're going to be perfectly happy with) and putting your anti-sway efforts up front is a decent way to go.
Your own experience with the kart should be pretty good for oversteer understanding. The front is lighter than the back ... if you skip and hop on cornering, you plant your foot on the right-hand pedal and it smooths out your track. Your stiffer rear suspension will always try to keep both of the back tires on the ground.
In the Speedster, you'll just have to wait until you're in the apex of the turn. You should be able to feel the differences in that back road you took us down off of 202, wouldn't you think?
If you find that the car seems to get a bit of an arched back in a hard corner, maybe limiter-straps are an alternative. You can always take them off when you're done driving the car hard.
Here's one you might not have in your folder, Bro:
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MIckey:
after reading (several times) the article on aircooled.net and thinking about my set up, I ended up with this:
1969 VW IRS rear suspension (NOT swing-arm)
205XR16 tires on 7" wide 911 Fuchs rims up front
225XR16 tires on 7" 911 Fuchs rims in back
19mm sway-away anti-sway bar up front
STANDARD HEIGHT front spindles (NOT drop-spindles)
Battery and compact spare both in front, as well as anything else with weight I could conveniently put up there.
Avis adjusters top and bottom on front, both adjusted equally
19mm Sway-away anti-sway bar in back
First, that's a lot of tire for a car as small, as low and as light as this, no doubt, and the 7" wide rims make them stay relatively flat on hard cornering. I also have a flared body, so these tires are outward, what?, something like 6-8" overall (side-to-side) more than stock. That makes a BIG deal on these cars.
Second, I noticed a reduction in steering effort in normal driving once the rear sway bar was installed. Didn't bother to do a study of why, it just was. I also noticed a somewhat harsher ride, especially with cracks in the pavement - you'll feel every one in the seat of your pants. You'll also corner flatter.....much flatter on any corner you hit. No surprise there, that's what I installed the rear bar for.
I've driven the car very hard at Roebling Road Race Course in Savannah
http://www.roeblingroad.com/track.html
along with other members of our local car club in hot pursuit, in particular a couple of well-set-up Cobras running VERY stout Roushe 427's, as well as a Carrera C4.
Admittedly, they have a lot more power than me, but I can out corner and pull away from any of them on the back corners at will. So far, I have understeer because the 148hp or so that I have isn't enough to overcome either the stickiness of the Continental tires or my courage or both. Believe me - I have pushed the living heck out of it on track corners and I can't make it oversteer (the rear won't come around to meet the front) but I CAN make it hang out there under moderate to full power and lock (you feel the sidewalls reach their limit) and it just digs and goes. I've also had a club member take pictures of it cornering on several different corners there, and if it's lifting a wheel I can't see it. The tires lock, the body plants and it goes.
I am absolutely certain that I could not corner like this with a swing-arm rear. I've driven race-prepared VW sedans with both swing-arm and IRS and there's no comparison. Oversteer is over-pronounced in a swing-arm car and the potential for buckling a rear wheel under on an oversteered corner is always present (although I never drove a sedan with tires/wheels on it as wide as mine).
Of course, if the Cobras get anything more than 30 yards of moderately straight track they're right back on my rear nerf bars, but that's life.
I've also let an SCCA Race Driving instructor drive it on the track and his best comment was: "Hey! THAT was FUN! Corners like a Bansheee!", so I guess I got what I wanted, even with the harsher ride. (He also had lap times somewhat lower than mine!)
Hope this helps......
gn
BTW: the picture below is at Roebling Road, just fooling around (hence, no helmet) but that's coming out of turn 5 (the big lobe on the right rear in the track schematic) at about 80.
after reading (several times) the article on aircooled.net and thinking about my set up, I ended up with this:
1969 VW IRS rear suspension (NOT swing-arm)
205XR16 tires on 7" wide 911 Fuchs rims up front
225XR16 tires on 7" 911 Fuchs rims in back
19mm sway-away anti-sway bar up front
STANDARD HEIGHT front spindles (NOT drop-spindles)
Battery and compact spare both in front, as well as anything else with weight I could conveniently put up there.
Avis adjusters top and bottom on front, both adjusted equally
19mm Sway-away anti-sway bar in back
First, that's a lot of tire for a car as small, as low and as light as this, no doubt, and the 7" wide rims make them stay relatively flat on hard cornering. I also have a flared body, so these tires are outward, what?, something like 6-8" overall (side-to-side) more than stock. That makes a BIG deal on these cars.
Second, I noticed a reduction in steering effort in normal driving once the rear sway bar was installed. Didn't bother to do a study of why, it just was. I also noticed a somewhat harsher ride, especially with cracks in the pavement - you'll feel every one in the seat of your pants. You'll also corner flatter.....much flatter on any corner you hit. No surprise there, that's what I installed the rear bar for.
I've driven the car very hard at Roebling Road Race Course in Savannah
http://www.roeblingroad.com/track.html
along with other members of our local car club in hot pursuit, in particular a couple of well-set-up Cobras running VERY stout Roushe 427's, as well as a Carrera C4.
Admittedly, they have a lot more power than me, but I can out corner and pull away from any of them on the back corners at will. So far, I have understeer because the 148hp or so that I have isn't enough to overcome either the stickiness of the Continental tires or my courage or both. Believe me - I have pushed the living heck out of it on track corners and I can't make it oversteer (the rear won't come around to meet the front) but I CAN make it hang out there under moderate to full power and lock (you feel the sidewalls reach their limit) and it just digs and goes. I've also had a club member take pictures of it cornering on several different corners there, and if it's lifting a wheel I can't see it. The tires lock, the body plants and it goes.
I am absolutely certain that I could not corner like this with a swing-arm rear. I've driven race-prepared VW sedans with both swing-arm and IRS and there's no comparison. Oversteer is over-pronounced in a swing-arm car and the potential for buckling a rear wheel under on an oversteered corner is always present (although I never drove a sedan with tires/wheels on it as wide as mine).
Of course, if the Cobras get anything more than 30 yards of moderately straight track they're right back on my rear nerf bars, but that's life.
I've also let an SCCA Race Driving instructor drive it on the track and his best comment was: "Hey! THAT was FUN! Corners like a Bansheee!", so I guess I got what I wanted, even with the harsher ride. (He also had lap times somewhat lower than mine!)
Hope this helps......
gn
BTW: the picture below is at Roebling Road, just fooling around (hence, no helmet) but that's coming out of turn 5 (the big lobe on the right rear in the track schematic) at about 80.
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Thanks Gordon! I figure it'll go like this: Once I finish the front brake conversion and reposition the rear shocks and put the rear sway bar on, and once the engine, trans, ect are in, I'll get a front and rear alignment and see what I have. Then I can start to tinker a little with shocks, caster, camber, toe in and the rest. I get the feeling with these cars there is no 'standard' whenit comes to this stuff. It all depends on what you're trying to do. I'm hoping to get it all sorted out by the end of the season. If all goes well I'll only have to paint and do the interior.
Gordon,
Loved your post. Your setup is virtually identical to mine, with the only exception of having 8 inch rear Fuchs instead of 7s. Everything you say is right on the money. Your observation of "hanging" the rear end out just a bit is consistent with my experience (though I am limited to vacant public roads!). At first I thought I must be mistaken, because everyone talks about how the rear end suddenly breaks away and off the track you go. As you say - au contraire! You CAN slide it out just a bit and it comes back very nicely with your (and mine) setup. Not at all bad for a 39 year old VW and (in my case) a driver that was born about the time that Dr. Porsche designed that suspension.
Loved your post. Your setup is virtually identical to mine, with the only exception of having 8 inch rear Fuchs instead of 7s. Everything you say is right on the money. Your observation of "hanging" the rear end out just a bit is consistent with my experience (though I am limited to vacant public roads!). At first I thought I must be mistaken, because everyone talks about how the rear end suddenly breaks away and off the track you go. As you say - au contraire! You CAN slide it out just a bit and it comes back very nicely with your (and mine) setup. Not at all bad for a 39 year old VW and (in my case) a driver that was born about the time that Dr. Porsche designed that suspension.