Solid Axle Vs. IRS For Road Racing

[79TransAm]

I'm planning on building a 79 TATA for driving on the street and occasional road racing. I also want it to stand out from the crowd. We had a 02 Z06 come into the shop at my work yesterday and I was thinking bout using one of the rears for my car. How hard and expensive do you think this would be. I was originally gonna use the ride tech 4 bar system for the rear. Would I possibly be able to still use that? Or would it not be worth the trouble for a car thats only gonna get occasional track time?

[vintageracer]

A lot of work for not much gain! That assumes that since you did not mention as front suspension upgrade you are not going to install a front suspension that will match the rear suspension you describe. There are suspension systems/products out there that will make your car far out-handle your ability to drive the car. Unless you want to spend LOT'S of money on parts and LOT'S money/time for fabrication, buy a car done or buy a proven suspension system and install it on your car.

The easist and cheapest was to improve 5-10 seconds a lap at an open track event is to spend BIG money with a top notch driving school and really LEARN HOW TO DRIVE a car fast and safe. None of us are as good a driver as "we" think we are!

[astroracer]

This subject gets beat to death here but I'll post my .02 cents... again...
The first thing I want you to do is re-read your initial post and think about how the car will be used. Really...and, if the hi-tech/wow-factor of an IRS is high on your list, read no further...
I thought long and hard about the rear suspension for my Astro project. My Astro is designed as a street driver. It MAY see a track but that, honestly, will probably never happen. I looked at 4 links, 3 links, panhard bar vs triangulated, you name it... I looked at it. The conclusion I came up with was, if this is a "street" oriented car that you want to DRIVE, stick with leaf springs. There is no better suspension for a street driver. If the car does see some track time the leaf spring suspension can put up good numbers with a little tuning. Good articulation, no binding, no hiem ends to rattle or wear out, fully tuneable with a pair of adjustable shocks and some front hanger and shackle mods. Once set-up, this suspension is, essentially, a zero maintenance suspension. Running polygraphite bushings will stiffen it up and sway bars are a dime a dozen for experimenting with diameters.
Granted there are better RACE suspensions available but that is what they are... race suspensions... They were never designed nor intended to manuever a city or country road with potholes and speed bumps... In my book the binding, high maintenance and pothole vunerability of these suspensions just can't be justified on a street driver.
I am sure there will be arguments, that's fine, this is just my opinion. When I build a car to drive, I want to DRIVE it, not spend countless hours underneath it adjusting, re-adjusting and replacing parts in a high strung suspension that will NEVER be utilized to it's full potential.
Mark

[novanutcase]

First, let me say that I am in no way qualified to say that I know beans about rear suspensions but I will say this. Part of the reason that we modify our cars is to go fast, but part of it is also the WOW factor. C'mon be honest! If it wasn't then why would we be putting on billet parts and the such. As far as the IRS, I wonder why every car manufacturer on the planet uses them. Yes, they are expensive but that is exactly my point. Since they are so expensive then why wouldn't car manufacturers use a solid axle with a triangulated 4 bar? Wouldn't this be better for them since these parts would be easier and cheaper to manufacture? Why don't todays cars have leaf springs? I think that for most of us that are going to be driving on the street, if you have the money, an IRS is the way to go. It's pretty much set it and forget it and I think that it can handle most situations the streets can throw at you better than most of the other setups which are made for more controlled situations.