Couple questions?
Couple questions?
on 2" drop springs i know you can run 18's with them wrapped in 35's but car have them wrapped in 40's and make clearence for the tire with no rub? If i drop my car 2" will a 3" exhast make enough clearence for the road not to hit anything like speed bumps? Does any one have a silver, gray car (perfer gunmetal) and have either a all black interior or a 2 tone interior with black and gray
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From: Elgin, IL
Car: 1997 Corvette
Engine: LS1
Transmission: 4L60E
Axle/Gears: 2.73 IRS
As for what fits, that would depend on the width of the tire as well. Do you want to run 215/40R18s or 295/40R18s? Obviously exaggerating to create a point. My car has 275/40R18 in the back with DropZone springs (1.75" drop?) and the only time I ever get any tire-to-car contact is when I make a sharp right turn, but that will be fixed as soon as I get my custom panhard rod installed
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Joined: Mar 2004
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From: Clearfield,Utah
Car: 1987 IROC, 1989 IROC
Engine: built 305, stock 305 tpi
Transmission: Corvette 700r4, t-5
Axle/Gears: 4.10 posi, 3.08 posi
when you drop your car with the stock panhard bar what happens? do you need an adjustable one?
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From: Elgin, IL
Car: 1997 Corvette
Engine: LS1
Transmission: 4L60E
Axle/Gears: 2.73 IRS
I live in Bloomingdale, not Bloomington 
Yes, you need an adjustable panhard rod when you lower your car or you will get rubbing issues like I get. I'm going to pick up my adjustable bar whenever me and the guy that made it are both free at the same time

Yes, you need an adjustable panhard rod when you lower your car or you will get rubbing issues like I get. I'm going to pick up my adjustable bar whenever me and the guy that made it are both free at the same time
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Joined: Mar 2004
Posts: 948
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From: Clearfield,Utah
Car: 1987 IROC, 1989 IROC
Engine: built 305, stock 305 tpi
Transmission: Corvette 700r4, t-5
Axle/Gears: 4.10 posi, 3.08 posi
so it basically pushes the car to one side right? would it hurt anything to run with out a pan hard bar until i can buy one?
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From: DC Metro Area
Car: 87TA 87Form 71Mach1 93FleetWB 04Cum
OK, one more time… measure the length of the panhard rod and then pull out your HS trig… you’ll find that lowering the car 1” will move the axle over roughly .01”. If you look in your FSM, you’ll find that the factory tolerance for location is somewhere in the +/-3/16” range, meaning that that .01” dislocation is roughly 2.6% of the acceptable dislocation as per the factory tolerances.
That being said, you’ll find that cars really did come from the factory with the rear axle located all over that range, so you might actually end up with the rear better or worse centered after lowering it. Second, if you really think you’ll see .01 or even if you _really_ dropped the thing, .02” change with your naked eye then… I’m impressed.
An adjustable panard rod does not fix any geometry problem caused by lowering the car, and is in no way necessary. It does compensate for the tolerances built into the car, but is only necessary for getting things dead even so that you can maximize the tire size that you run on the back of the car, but of course, if you’re running a near stock size then you aren’t going to have an issue anyway.
That being said, you’ll find that cars really did come from the factory with the rear axle located all over that range, so you might actually end up with the rear better or worse centered after lowering it. Second, if you really think you’ll see .01 or even if you _really_ dropped the thing, .02” change with your naked eye then… I’m impressed.
An adjustable panard rod does not fix any geometry problem caused by lowering the car, and is in no way necessary. It does compensate for the tolerances built into the car, but is only necessary for getting things dead even so that you can maximize the tire size that you run on the back of the car, but of course, if you’re running a near stock size then you aren’t going to have an issue anyway.
depends on your offset... tire brand, wheel width and many other examples. for the fronts a 245/40/18 is perfect on an 8-8.5" wheel and you will have no issues with rubbing assuming that you stick to a 4.5 or 4.75 backspacing/offset. any wider of a rim, larger tire or different offset you may have issues.
for the rear it's an entirely different issue... a 265/40 or 35 should be no problem, however again it depends on the width of the rim and the offset/backspacing to wether it will fit.
for the rear it's an entirely different issue... a 265/40 or 35 should be no problem, however again it depends on the width of the rim and the offset/backspacing to wether it will fit.
ok ive change my whole setup this is what im wanna go for dropzone springs 1.75", billeston shocks and struts and for the front wheels im going for 245/40/18 and the rear 275/35/18 the front wheels are 8 in wide and the rears are 9 1/2 both tires are both about .3 and .4 shy of 26 in tall
Originally posted by unbonyr
so you think 245/40 in the front and 265/40 in the back will have no issues with a 2 inch drop with about a 8 in wheel 8 1/2 the biggest
so you think 245/40 in the front and 265/40 in the back will have no issues with a 2 inch drop with about a 8 in wheel 8 1/2 the biggest
245/40/18 on a 18x8 wheel with a 4.75 with baer brakes. basically a 4.5" backspacing if you have stock disc brakes in the front would look the same.
Last edited by Kandied91z; May 23, 2005 at 08:01 PM.
how low of a drop do you have on you car kandie, do you think i could put 285/35 on a 9.5 in wide wheel and what should my backspacing be for my wheels front and back cuase i have no clue wat backspacing is
Last edited by unbonyr; May 23, 2005 at 08:23 PM.
backspacing is very personal but there is a guideline which can be found just by checking out other cars on here. as far as my drop, it's airride so it's adjustable...
yes you could fit a 285/35 on a 9.5x18. my street tire was a 285/35/18 on my last 10" wheel. i used the 295 for drag racing.
yes you could fit a 285/35 on a 9.5x18. my street tire was a 285/35/18 on my last 10" wheel. i used the 295 for drag racing.
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Joined: Jan 2000
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From: Santa Rosa, CA
Car: '91 Formula
Engine: L98
Transmission: 700R4
18x9's Up Front??
I'm sorry if I'm rehashing things already discussed, but I don't feel I've found a clear answer to my search in this post so far. I contacted GroupAWheels for some 17x9" wheels, and they didn't have that style and size in stock for my car, but they do have the 18x9" size. From what I've gathered, an 18x9" rim shouldn't have too much of a problem fitting in the rear unless there's some real geometry problems, but I'm a little concerned with the front. With stock backspacing/offset, and stock brakes on a slightly lowered car, do 18x9's with let's say a 275mm tire width fit up front without rubbing or causing problems??
will it bolt up with ease assuming it's the right offset? yes.
will a 275 cause problems in the front on a lowered car? depends on how lowered. 275 is very wide tire for that area. with the proper offset... which would have to be different the factory to really make it work you could make it work with a minor lowering with such a vehicle. you could not have such extreme lowering as above but that's an extreme case anyhow.
i had 275's on the front using a 9.5 wide rim. it tracked all over the street and slowed my car down. never again. you really should use a 265 for your 9" wide tire anyhow and that might make enough of a difference to make it easier to fit.
in the end it will take some research and work from you to get it just right. 8"-8.5" wide is really the ideal width on our cars for lowered vehicles but that doesn't mean it can't be done if you want it to. your strut choice also makes a difference. anything larger then a 2.5" diameter will throw all of your equations off. for example bilsteins are a 3" diameter shaft so you will have to be careful on what your running.
just more to consider...
will a 275 cause problems in the front on a lowered car? depends on how lowered. 275 is very wide tire for that area. with the proper offset... which would have to be different the factory to really make it work you could make it work with a minor lowering with such a vehicle. you could not have such extreme lowering as above but that's an extreme case anyhow.
i had 275's on the front using a 9.5 wide rim. it tracked all over the street and slowed my car down. never again. you really should use a 265 for your 9" wide tire anyhow and that might make enough of a difference to make it easier to fit.
in the end it will take some research and work from you to get it just right. 8"-8.5" wide is really the ideal width on our cars for lowered vehicles but that doesn't mean it can't be done if you want it to. your strut choice also makes a difference. anything larger then a 2.5" diameter will throw all of your equations off. for example bilsteins are a 3" diameter shaft so you will have to be careful on what your running.
just more to consider...
well i was goin get the bileston shocks and struts how bad will that mess things up and im thinking im just goin go back to my orignal with dropzone springs 1.75'' drop or the intrax 2'' drop springs. and 245/40/18 on a 8in wide rim
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