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WIKDCUT
07-12-2011, 06:52 PM
Ok, first off I love the look of slammed muscle cars and late models as well as trucks. There is just something about wheels and tires tucked up into the fender wells that make cars and trucks look absolutely sinister. Stance is everything when it comes to looks.

The question that I have been wondering for years is how all of these cars are able to turn without major rubbing issues. My car is equipped with Air Ride so I can slam it in the parking lot but ride height is quite a bit higher in order to have no tire rub issues. Many of these Pro Touring cars are equipped with coilovers without that option. They tuck massive tires and wheels AT RIDE HEIGHT and they are driven hard at autocross and road race events. It seems to me that these cars can't have a very tight turning radius yet they are raced.

My question is, what is the secret? How do all these cars do it? The G Force Cuda is a perfect example. I realize that it was built for straight line speed and braking and mostly show but its cars like that I wonder how they do it.

Anyone care to share the secrets to tires clearance and rubbing issues? Thanks.

robertjra
07-12-2011, 08:03 PM
mini tub kits and narrowed rear ends, front after market front sub frames and rolled fenders and the right back space on the wheels that is all you need to know!!! (in a nut shell)

79-TA
07-12-2011, 09:51 PM
and the occassional 4 pound sledge hammer

Ash
07-13-2011, 12:21 PM
I've wondered that myself. Not on the rear, but on the front. The front wheels are pretty flush with the fender at ride height, and the fender drapes over the top of the tire. "Big Red" is a perfect example. It looks like a sharp turn is impossible, not on the inward facing wheel, but the outward one. I can't find any picks of it with a partial or full lock outward turn.

vette427-sbc
07-13-2011, 02:50 PM
Fender rolling, and perfect backspace.
Heres my car at full compression. Close, but it doesnt rub!
https://static1.pt-content.com/images/pt/2011/07/DSCF1153-1.jpg
https://static1.pt-content.com/images/pt/2011/07/DSCF1154-1.jpg

At ride height, the tire is tucked in about .5-.75"

If you think about it, the wheel "loses" diameter at the point of contact on the fender when it turns. Notice on the last pic that the point where the tire would contact the fender is no longer the center of the wheel.

Bill Howell
07-13-2011, 03:07 PM
The G-force Cuda was not made just for straight line stuff. It absolutely was slammed and never scrubbed. The secret to it and any build is doing it right and spending the money to do it right. Bob Johnson has always said anyone can give a car the "look", its the making it work part that is expensive and he was right, lowering the body over the frame is part of it. The Cuda had Superbird style outlets over the tires, but functionally they were there for clearence. A huge part of this is doing your homework, taking proper measurements and double checking everything. Otherwise you end up with expensive wall art. Funny thing about the cuda, it has 6 or 7 inches of clearance under it, whowooda thunk?

Matt@BOS
07-13-2011, 03:49 PM
Bill pretty much summed it up. The G-Force Cuda did it without any compromises, which meant that the whole car was designed around that stance in mind.

After my last autocross, my front springs settled a little bit more, and by the end of the afternoon, the front was really low. I think the wheel opening was about even with the rim. The wheel might have even tucked 1/8." Still, I never had any problems with rubbing, even after two days of throwing it around cones. I attribute this to several things ranging from: 1. aftermarket subframe, 2. larger inner fenders, 3. rolled fenders, 4. dead on backspacing.

That is about all that has been done to my car. Now, doing all of this is relatively easy. Not hitting speed bumps is the hard part:)

Matt

CFster
07-13-2011, 04:01 PM
Proper suspension geometry. With the correct camber curve once the suspension compresses the top of the tire has moved inwards from the fender lip.

TonyL
07-13-2011, 04:05 PM
Proper suspension geometry. With the correct camber curve once the suspension compresses the top of the tire has moved inwards from the fender lip.


That. Many older cars lack this camber curve, but with the proper upgrades it can be corrected.

Ash
07-13-2011, 05:21 PM
Those pics are Sauce..thanks for the further explanation. vette427-sbc, do you have a pic of the wheel turned outward with the same P.O.V.?

WIKDCUT
07-13-2011, 05:25 PM
I seem to notice that a lot of these cars seem to have the outside of the tire quite a ways inboard from the inner edge of the fender too. Some of them I just can't figure out but I guess that is part of the allure. Project II Much is another example of a completely slammed car that tucks tires way up yet is raced.

WIKDCUT
07-13-2011, 06:10 PM
https://static1.pt-content.com/images/pt/2011/07/hrdp_1102_35_oholley_ls_festmark_stielow-1.jpg

Here is Red Devil. Unreal that the tires don't rub.

Another.https://static1.pt-content.com/images/pt/2011/07/DSC_6662-1.jpg
Here is II Much.https://static1.pt-content.com/images/pt/2011/07/2qsyof5-1.jpg
And of course the aforementioned G Force Cuda.https://static1.pt-content.com/images/noimg.gif
Keep in mind that all of these cars are coil over cars, no air. I have seen the G Force Cuda in person as well as many other slammed pro touring rides and still cannot believe that they have no rubbing issues.

WIKDCUT
07-13-2011, 06:25 PM
Here's Big Redhttps://static1.pt-content.com/images/pt/2011/07/2774509480_2d7ef5f827-1.jpg

sn75
07-13-2011, 07:38 PM
I'm sure most, if not all (for the most part) have "some" rubbing, but most just deal with it. My Chevelle is only lowered about an 1.5" front/rear and when I'm taking corners fast and hit dip/bumps/large undulations in the road I get some rub (real quick, but rub). Do I care, no (if I did I would ditch the 18" wheels and go with a different diameter wheel with more backspacing and/or different height tire).

Ron S
07-14-2011, 02:08 AM
My Mustang is pretty low,I think its less then 4" at the rockers. The poor thing has really been leaned on, and it doesn't rub. I say, you make the body fit the tires, not the other way around. Ron

https://static1.pt-content.com/images/pt/2011/06/5862000770e71e48f263b1L-1.jpg

elitecustombody
07-14-2011, 04:15 AM
Using right offset wheels helps,but to have it tucked and not rubbing like on G-Force Cuda,takes a lot of fabrication .It's either channeling the body, building custom control arms,building custom chassis for wheels/tires to fit stock body or modify the fenders to accommodate wheels/tires or a bit of everything.

Ron, good looking Mustang.

parsonsj
07-14-2011, 05:15 AM
Project II Much is another example of a completely slammed car that tucks tires way up yet is raced.Putting the car at that ride height without rubbing took a *lot* of work. A quick list:
1. Complete custom floor. I cut the floor out of car and lowered the body over a custom Art Morrison frame.
2. Custom inner wheel housings, both front and back.
3. Hand-built suspension.
4. Shaved wheel flanges in back
5. Replaced front wheel flanges with 1/4" stainless steel rod in front
6. Perfect backspace, spec'ed to the 1/8"
7. Notched frame (yes, even after all that, I had to notch the Morrison frame) for full wheel lock turns.

And even then, I had to have the rear end narrowed 1/4" per side. The point is that the entire car was built for that ride height, and it took hundreds of hours to get it to work. You can't get a basically stock car to look like that and still work.

jp

406 Q-ship
07-14-2011, 06:35 AM
Putting the car at that ride height without rubbing took a *lot* of work. A quick list:
1. Complete custom floor. I cut the floor out of car and lowered the body over a custom Art Morrison frame.
2. Custom inner wheel housings, both front and back.
3. Hand-built suspension.
4. Shaved wheel flanges in back
5. Replaced front wheel flanges with 1/4" stainless steel rod in front
6. Perfect backspace, spec'ed to the 1/8"
7. Notched frame (yes, even after all that, I had to notch the Morrison frame) for full wheel lock turns.

And even then, I had to have the rear end narrowed 1/4" per side. The point is that the entire car was built for that ride height, and it took hundreds of hours to get it to work. You can't get a basically stock car to look like that and still work.

jp

John pretty much covered it if your not willing to compromise. If you just want to lower a car with out building your own suspension system then it requires alot of measurement and compromises in tire size or on how low the vehicle can be in the real world. I will know the tire that I would like to run and then play with rim sizes to make it work with in the envelope I have, it requires alot of time, measurements, and moving suspension through its full expected range of motions. Now when all that is said and done my cars will usually have a light rub when the front end is turned to full lock and the suspension goes into heavy compression (an unexpected dip when turning). When things get tight for clearance then thinking of how the wheel will deflect underload, it might require a solid or stiffer suspension bushing to keep the tire off the bodywork. With the suspension it can be found that too fit a wheel you can make the vehicle not work or ride well, so this is where compromise kicks in. Ask yourself would you rather have huge wheel on the car at the expense of ride and handling? Of course there is always the hammer method to gain clearance, for the extreme a re-arched wheel opening will do the trick too.

wellis77
07-14-2011, 11:15 AM
7. Notched frame (yes, even after all that, I had to notch the Morrison frame) for full wheel lock turns.

Hey John, do you have any pics of the notch you made? I'm curious how you did it. I've been thinking about this recently and I'm pretty sure I'm going to have to do it. I've been on the II Much site a few times and I don't recall seeing the notch. I may have to look again. Thanks.

parsonsj
07-14-2011, 11:41 AM
Hi Will,

Go to my main page, and scroll to the bottom The photo second from the bottom shows the notch pretty well. I "wrapped" the back side of the notch with additional 2x4 tube, and filled the notch itself with bent 1/4" plate. That was hard work, bending that 1/4" plate.

Hope that helps.

Tony_SS
07-14-2011, 12:12 PM
Proper suspension geometry. With the correct camber curve once the suspension compresses the top of the tire has moved inwards from the fender lip.

Interesting. I like to think this is the case for me.. I run 3" drop springs from OPGI and a Stage II from Marcus. I had a buddy spend a couple hours setting up the SPC arms with the alignment specs from the kit. And I have run a 17x8 with 3.5"bs and and 4.5"bs. No rubbing on either one ever.

The question is, what about when you're running an Air Ride system like the OP is? I imagine you set the alignment specs at the desired ride height and drive it as such. So essentially, there should be 2 settings when you're running an air ride system. Driving and Parked.

John Wright
07-14-2011, 12:13 PM
When lowering take this into account: suspension travel
The handling can go from neutral to pushing in one single bump...the suspension runs out of travel and everything packs out solid....very disasterous if it happens in a corner with some speed.

DriverzInc
07-14-2011, 12:20 PM
mini tub kits and narrowed rear ends, front after market front sub frames and rolled fenders and the right back space on the wheels that is all you need to know!!! (in a nut shell)


exactly...

Alot of cars are built around the wheel and tire, at ride height. Order your wheels they way you want them to look, and build the car around them is a common practice. Other tricks of the trade are running a slightly narrower wheel for a front subframe then suggested, like SpeedTech's front subframe will take up to a 10" wheel with a 275 wide tire, but for the LOW riders, I'd suggest a 9 or 9.5 with a 265-275. Narrower wheel pinches the tire just a bit, which in some cases looks better anyway, will also leave you some tire bulge to protect your rim, and help clear better at a lowered ride height. All things relative, bigger isn't "always" better.

Ripped
07-14-2011, 02:10 PM
It's a process, especially on the front.

On the rear, the only issue I had to confront was the axle hitting the exhaust pipe, where it loops over the axle, under full suspension travel. (less clearance)

The front, was 2 tire size changes, an "adjustment" on both the wheel backspace, and shaving the hub face on the wheel. Next the wheel was hitting the UCA's under full turn.

Both sets of fender lips were rolled long before the car was painted or bodywork was done. I also changed the front radius of the front of the fender, where the tire comes close, under full turn. I run a very agressive camber, which helps also.

I have a couple things left to solve, is the headers and exhaust, which will contact speed bumps etc. I was planning on possibly ordering another set of tri-y headers, and modifying the collector area, raising it if possible.
Next, I have to make a custom oil pan, or run a dry sump system. (tagged that once)

I don't have air bags and I refuse the raise the car LOL

wellis77
07-15-2011, 01:11 AM
Hi Will,

Go to my main page, and scroll to the bottom The photo second from the bottom shows the notch pretty well. I "wrapped" the back side of the notch with additional 2x4 tube, and filled the notch itself with bent 1/4" plate. That was hard work, bending that 1/4" plate.

Hope that helps.

Thanks John, definitely helps. I've seen that pic before, just never noticed the notch. Very subtle, and nice work bending 1/4" plate. Thanks again.

Hunter68
07-17-2011, 03:56 PM
how are you supposed to know what your camber, and all that is supposed to be?

Norm Peterson
07-20-2011, 04:00 AM
Experience, research, testing, and some ability to visualize in 3-D.


Norm

Hunter68
07-21-2011, 07:09 AM
but that could be some body damage if its your first time like it would be for me and that could be a lot of money already spent to figure out its not right