[enkeivette]

You already have to drop the motor out of the bottom of the car and dismount it to install long tubes, so how much more difficult can it get?

And no, all street cars are not built with understeer. Most are, yes. But the two examples that I've been leading with both have an oversteer bias from the factory.

Your philosophy sounds intelligent, but any way you slice it, with a front engine rear drive car that already has a tendency to oversteer, putting more weight in the back is just going to make that worse. Bet on it.



I'm not making any claims about rear engine cars.

[Ultraperio]

Originally Posted by enkeivette

You already have to drop the motor out of the bottom of the car and dismount it to install long tubes, so how much more difficult can it get?

And no, all street cars are not built with understeer. Most are, yes. But the two examples that I've been leading with both have an oversteer bias from the factory.

Your philosophy sounds intelligent, but any way you slice it, with a front engine rear drive car that already has a tendency to oversteer, putting more weight in the back is just going to make that worse. Bet on it.



I'm not making any claims about rear engine cars.

You have to separate over-steer due to chassis setup and oversteer due to which wheels are driven.

When I talk about over-steer and under-steer I'm talking about steady state cornering tendencies with no throttle influence. Sure you can get any reasonably powered RWD car to over-steer very easily, but that is an entirely separate issue from the chassis tendencies. I haven't driven a viper so i cant speak from experience, but i do know at the limit(however high) late model corvettes tend to under-steer. You're not going to get a corvette to over-steer unless you give it some power, turn in under hard braking, or give it a scandinavian flick.

You are making blanket statements about over-steer. A rear biased car will not always over-steer more than a front biased car. For instance again under hard braking in a turn a front biased car can unload the rear wheels to the point of loss of traction. In a rear biased car the additional weight over the rear wheels might keep them loaded up and prevent over-steer.

Another example on the other hand is what jedhead alluded to. A rear heavy car will tend to under-steer on corner exit under power. This is because of the weight transfer unloading the front wheels. A front heavy car will plant more effectively on corner exit under power. This is actually the current GT2's achilles heel as it has too much power and too little weight in the front causing near loss of control(due to under-steer) under hard acceleration in a turn.

[enkeivette]

No blanket statements. Statements from reading motor trend magazine for years. They tested all the hot cars a few years ago and published a report. Vipers and Vettes had slight oversteer. And I'm pretty sure they know the difference between breaking the tires loose with the motor and breaking the tires loose with lateral g force.

So, yes, a Corvette will oversteer in neutral. Wanna go for a ride? I'll show ya. And as physics would have it, more weight in the rear would make that bias worse.


The Corvette frame has been completely transformed 3 times since my frame was conceived in 1963. The front end is about 2 feet shorter now and the transmission is in a different spot. I don't believe that maintaining a 50/50 weight distribution again and again was an accident. Too much has changed and the weight distribution is no accident. The fact that the other American front engine rear drive supercar has almost the exact same weight distribution with a different frame, engine, and transmission location is no coincidence either.

I'm not saying they got it exactly where they wanted it, I agree there is always a need to compromise. But I'll bet 50/50 was and always has been their goal.

[BRUTAL64]

[BRUTAL64]

Originally Posted by Ultraperio

Another example on the other hand is what jedhead alluded to. A rear heavy car will tend to under-steer on corner exit under power. This is because of the weight transfer unloading the front wheels. A front heavy car will plant more effectively on corner exit under power. This is actually the current GT2's achilles heel as it has too much power and too little weight in the front causing near loss of control(due to under-steer) under hard acceleration in a turn.

Well, I'd like to agree-- but my C2 may have it own ideas. It goes into the corner with a little under steer and goes to OVER STEER in the middle and neutral out.

That's with a 47/53 weight. Over the years it has always been this way.

[Ultraperio]

Originally Posted by enkeivette

No blanket statements. Statements from reading motor trend magazine for years. They tested all the hot cars a few years ago and published a report. Vipers and Vettes had slight oversteer. And I'm pretty sure they know the difference between breaking the tires loose with the motor and breaking the tires loose with lateral g force.

So, yes, a Corvette will oversteer in neutral. Wanna go for a ride? I'll show ya. And as physics would have it, more weight in the rear would make that bias worse.


The Corvette frame has been completely transformed 3 times since my frame was conceived in 1963. The front end is about 2 feet shorter now and the transmission is in a different spot. I don't believe that maintaining a 50/50 weight distribution again and again was an accident. Too much has changed and the weight distribution is no accident. The fact that the other American front engine rear drive supercar has almost the exact same weight distribution with a different frame, engine, and transmission location is no coincidence either.

I'm not saying they got it exactly where they wanted it, I agree there is always a need to compromise. But I'll bet 50/50 was and always has been their goal.

50/50 may have been the goal. 50/50 weight distribution may indeed be the best compromise for a street car but this does not make it ideal. What i am saying is in terms of outright performance a rearward weight bias allows for quicker changes in direction and better braking performance which is proven time and again by purpose built race cars and very high performance street cars.

[Ultraperio]

Originally Posted by BRUTAL64

Well, I'd like to agree-- but my C2 may have it own ideas. It goes into the corner with a little under steer and goes to OVER STEER in the middle and neutral out.

That's with a 47/53 weight. Over the years it has always been this way.

Again, over/under steering tendencies are not just effected by weight bias. Suspension setup/alignment, damper and spring rates, and relative tire sizes pressures and compounds all greatly effect a cars tendencies around a corner.

Besides, 47/53 isn't exactly what I'd call 'tail heavy'

[enkeivette]

Originally Posted by Ultraperio

50/50 may have been the goal. 50/50 weight distribution may indeed be the best compromise for a street car but this does not make it ideal. What i am saying is in terms of outright performance a rearward weight bias allows for quicker changes in direction and better braking performance which is proven time and again by purpose built race cars and very high performance street cars.

The Viper broke the lateral G record in 97 with its 50/50 weight distribution, not sure who has it now. Probably the Mosler, but that's not really a fair take since the Mosler comes factory with slicks.

I won't argue your point about race cars, because I really don't know. And maybe a rear weight bias works better with Porsches and Ferraris, I really don't know. But it doesn't with Vettes and Vipers, so I really can't agree that your theory has been proven time and time again with very high performance street cars. Unless you can provide examples like I've been doing.

IRAC-RAFADC!

[Chuck]

I am with Brutal on this one!

[Vettezuki]

Originally Posted by enkeivette

. . .

Your philosophy sounds intelligent,

Actually, it's called physics. Different discipline.

but any way you slice it, with a front engine rear drive car that already has a tendency to oversteer, putting more weight in the back is just going to make that worse. Bet on it.



I'm not making any claims about rear engine cars.

Out of curiosity, what mystical life force differentiates a FRWD with say 45/55 and RRWD with 45/55 all other things being equal? We're controlling for weight bias (and punting on mass centralization a bit).