I'm aware that IRS is generally regarded as 'better', however I was wondering if there's a case for a swing axle set up on a 356 replica? (other than being closer to an original 356) what are the pros and cons? And what set up are you running?
Cheers
Dan.
IRS vs Swing Axle
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mdmax72
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Here's my thoughts.
First, SUSPENSION GEOMETRY: In a nut shell, swing arm wheels don't go straight up and down - they travel around an arc of about 18 inches. As they go up, the bottom of the wheel goes out. As they go down, the bottom of the whel goes in and begins to tuck under. Hold your arm straight out at your side, fingers pointed straight down. As you raise your arm, your finger tips will angle out - that's what your wheel does.
When you install a camber compensator you are putting a leaf spring across the bottom of the axles (or swing arms, if you prefer) which is meant to (a.) hold both wheels parallel to each other as much as possible and (b.) attempt to keep the rear wheels on the ground and NOT tuck under on hard corners. The harder you take a corner, the more likely a rear wheel will, with the movement of the body from a "flat" line, try to tuck under and THAT causes less and less of the tire tread to remain on the ground. It has no choice - that's the way the susension geometry works. If a wheel tucks under and loses a significant amount of tire tread ground patch (it actually pulls up to 75% of the tread patch up off the ground from the inside to the outside), then it is possible to have a catastrophic event occur where the car can actually flip over as it rolls onto the outside edge of the Tyres.
The camber compensator will alleviate some of the oversteer which causes the movement of the rear axles, but it can't correct it - remember, those wheels HAVE to move that way and all you can do is try to limit some of the movement which will push the catastrophic event farther out in the performance profile.
Now, with IRS, the wheel is rigidly held by a triangular assembly (diagonal arm and spring plate) which holds the hub and wheel in strict alignment as the wheel goes up and down. The wheel HAS to go straight up and down - that's the way the suspension geometry works with IRS. The important thing is that, as the wheel goes down, the bottom never tucks in. The geometry holds the wheel straight, and the tire patch is planted on the ground. There is also the issue of sidewall flex which is exascerbated with a swing arm suspension for the same reasons. Tuck a wheel under with a mushy sidewall on the tire and it just buries itself faster if the wheel itself is already angled onto the outside edge.
If you never go out on a road track and never push your car to the limits, you'll never see any of this stuff. If you have to ask what it all means, you'll probably be too scared to try to make it corner that hard in the first place and will never notice the difference.
Then there's the suspension geometry which is another thread, maybe
First, SUSPENSION GEOMETRY: In a nut shell, swing arm wheels don't go straight up and down - they travel around an arc of about 18 inches. As they go up, the bottom of the wheel goes out. As they go down, the bottom of the whel goes in and begins to tuck under. Hold your arm straight out at your side, fingers pointed straight down. As you raise your arm, your finger tips will angle out - that's what your wheel does.
When you install a camber compensator you are putting a leaf spring across the bottom of the axles (or swing arms, if you prefer) which is meant to (a.) hold both wheels parallel to each other as much as possible and (b.) attempt to keep the rear wheels on the ground and NOT tuck under on hard corners. The harder you take a corner, the more likely a rear wheel will, with the movement of the body from a "flat" line, try to tuck under and THAT causes less and less of the tire tread to remain on the ground. It has no choice - that's the way the susension geometry works. If a wheel tucks under and loses a significant amount of tire tread ground patch (it actually pulls up to 75% of the tread patch up off the ground from the inside to the outside), then it is possible to have a catastrophic event occur where the car can actually flip over as it rolls onto the outside edge of the Tyres.
The camber compensator will alleviate some of the oversteer which causes the movement of the rear axles, but it can't correct it - remember, those wheels HAVE to move that way and all you can do is try to limit some of the movement which will push the catastrophic event farther out in the performance profile.
Now, with IRS, the wheel is rigidly held by a triangular assembly (diagonal arm and spring plate) which holds the hub and wheel in strict alignment as the wheel goes up and down. The wheel HAS to go straight up and down - that's the way the suspension geometry works with IRS. The important thing is that, as the wheel goes down, the bottom never tucks in. The geometry holds the wheel straight, and the tire patch is planted on the ground. There is also the issue of sidewall flex which is exascerbated with a swing arm suspension for the same reasons. Tuck a wheel under with a mushy sidewall on the tire and it just buries itself faster if the wheel itself is already angled onto the outside edge.
If you never go out on a road track and never push your car to the limits, you'll never see any of this stuff. If you have to ask what it all means, you'll probably be too scared to try to make it corner that hard in the first place and will never notice the difference.
Then there's the suspension geometry which is another thread, maybe
Rich
DDK Member 0547
Evolving Speedster Build
DDK Member 0547
Evolving Speedster Build