Wider wheels and move suspension inward?

[Code510]

I've been thinking a little bit, so bear with me.

It seems one of the biggest factors that holds back these Pro Touring cars is tires. With the 200 treadwear, that limits the car quite a bit. My thought was if I could stuff a really wide tire up front, that would be a huge gain.

Then I thought I could build some one off suspension that was narrower, so the extra wide wheel could fit over that suspension.

And to get to my point: What if I moved the front suspension, both sides, inward 6" each? Just throwing a number out there. Then I could run a wheel that was 6" wider with offset?

I know this is probably crazy and doesn't work...but why not? The track width would be about the same. The only thing I can think is that the degrees of camber/caster and toe would change more dramatically.

Thanks for listening to my crazy idea. :) Hoping Mr. Sutton can chime in and school me on this.

[Ron Sutton]

You're on the right track about needing to run wider front tires.

But simply moving the suspension "in" is not a good way to get there. The scrub radius increases ... and you run into packaging problems. Either the UCAs & LCAs run into the engine & exhaust, or you make the UCAs & LCAs shorter. Both are bad.

I'll be unveiling a new track front suspension design on here in the near future that should give you some ideas.

Until then, best wishes. Ron Sutton

[jovozx12]

It seems to me that the reason for all the changes throughout the suspension travel is caused by the Unequal length of the upper and lower control arms. Could you narrow the frame a bit then add length to the uppers and shorten the lowers?

[BMR Sales]

Anumber of possible problems with that Idea - Putting a Motor in will be cramped if even possible, also Radiator. New Mounts, etc. Suspension Geometry.

T.C.

[Ron Sutton]

It seems to me that the reason for all the changes throughout the suspension travel is caused by the Unequal length of the upper and lower control arms. Could you narrow the frame a bit then add length to the uppers and shorten the lowers?

Hi Jovozx12*

That is the common way for hot rods, because they don't care about actual cornering performance.

I think what Code510* is asking about, is for actual handling performance on tracks, AutoX or curvy roads. Shortening the lower control arms is the one of the worst things you can do for the roll center. It migrates far & erratically during travel with short lower arms. Just the opposite ... longer lower control arms ... is the goal.

*Please post your names. I dislike talking to a handle.

[Code510]

Hi Ron,

I'm Tim. Sorry, I need to add that to my signature!

My idea...mounting engine and everything practical aside...is if I cut the cross member out, and moved both sides of the suspension in, but leave all the geometry of the suspension the same, would that handle better since the wheels could then be wider? I know there is gains in suspension geometry, but this is just purely going off going with a wider tire.

[Ron Sutton]

Hi Tim,

It's still the wrong direction. The key with wider tires is to build the wheels with deeper back spacing to reduce the scrub radius.

[Code510]

Hi Tim,

It's still the wrong direction. The key with wider tires is to build the wheels with deeper back spacing to reduce the scrub radius.

I gotcha. I figured it was wrong, or people would be doing it. Just need some confirmation on that.

Thanks again,

Tim

[whiteknuckle]

couldnt you just run a wider wheel and tire:headscratch: combo with the correct offset and be fine? assuming you are ok with going with a wider fender and some fender vents to release trapt air?

[TheJDMan]

Have you seen the One Lap Camaro? Rather than move the wheels inboard to gain clearance he had the front fenders modified to fit a wider wheel/tire combo. IMO, this is with out a doubt the best fender flare job I have ever seen because it is so subtle that you don't even notice it but the huge tires fit like a glove. Check out the pictures in this thread.

http://www.lateral-g.net/forums/showthread.php4?t=43688&highlight=lap+camaro

There is a thread on here that shows how the fenders were flared but I can't seem to find that thread just now.

Found it:
http://www.lateral-g.net/forums/showthread.php4?t=38370

[71RS/SS396]

Brian Finch and I did some testing last month and since our cars are essentially the same it was easy to do. He has (had) a 335 front tire and I have a 315. We swapped cars and I notice his car had quite a bit of oversteer on turn in, he was surprised at how much more balanced my car was. We swapped my wheels onto his car and it cured the oversteer with no other changes. Imho there's a point where you have too much front grip and it upsets the balance of the car.

[Payton King]

you not increase rear grip to balance the car instead of limiting front grip?

I believe both of you run the DSE rear...lower the panhard bar. I know it is not adjustable, but you could make it that way.

What is the track width on both cars? He could also increase track width in rear to tighten the car up...acording to Ron Sutton's teachings.

[syborg tt]

Tim Allens Camaro widen fenders and Quarter Panels.

I tried to get a picture of the stretch but it was a no go with the Camera.

http://garagescene.net/gallery3/var/resizes/Events/2013-Sema/2013%20Sema%20Tim%20Allens%2069%20LS%20COPO%20Cama ro%20%2816%29.JPG

http://garagescene.net/gallery3/var/resizes/Events/2013-Sema/2013%20Sema%20Tim%20Allens%2069%20LS%20COPO%20Cama ro%20%2806%29.JPG

http://garagescene.net/gallery3/var/resizes/Events/2013-Sema/2013%20Sema%20Tim%20Allens%2069%20LS%20COPO%20Cama ro%20%2805%29.JPG

http://garagescene.net/gallery3/var/resizes/Events/2013-Sema/2013%20Sema%20Tim%20Allens%2069%20LS%20COPO%20Cama ro%20%2810%29.JPG

http://garagescene.net/gallery3/var/resizes/Events/2013-Sema/2013%20Sema%20Tim%20Allens%2069%20LS%20COPO%20Cama ro%20%2812%29.JPG

http://garagescene.net/gallery3/var/resizes/Events/2013-Sema/2013%20Sema%20Tim%20Allens%2069%20LS%20COPO%20Cama ro%20%2801%29.JPG

Very cool well done Wide Body early 1st gen Camaro By Bodie Stroud Design for Tim Allen.

Spec that I am aware of
DSE Subrame, Connectors and Quadra-link, Brembo Brakes and custom Rallye style Wheels. 427 cubic in LS Dry Sump

[syborg tt]

Okay I am not a suspension guy and I don't claim to be either. However look at the new Z28 and it has 305's all the way around.

I've talked with the Lotus guys (Suspension & Chassis Engineer) for year about suspension and chassis design and they all agree more isn't always better. There is a balance and before you figure out the balance you have to know how to tune a suspension which I am willing to bet 99% have no clue how to actually do it.

I also talked with a couple guys at Ride-Tech at Sema and the subject of 295's all the way around came up and they thought it was a good idea and now you just have to figure out if all 4 tires should be the exact same height or should they be staggered. Lots to think about and I know there is a post from a couple years ago that I made that had some great information.

My future plans with my car is to run 295's on all 4 corners and spend a bunch of time tuning the suspension with someone that really understands how they work.

There are so many things to consider and I think it would be great if one of the experienced guys to chime on with suggestions as to what they think about the tire pressure, Spring rates, rebound, dampening, weight bias & so on as I really would like to learn as much as I can over the winter so I don't look like an idiot next year when we start to thrash on my camaro.

[Ron Sutton]

Hi Payton,

Why not increase rear grip to balance the car instead of limiting front grip?
Agreed.

I believe both of you run the DSE rear...lower the panhard bar. I know it is not adjustable, but you could make it that way.

What is the track width on both cars? He could also increase track width in rear to tighten the car up...acording to Ron Sutton's teachings.

That is stated backwards. Narrowing the rear track will tighten the car up. Widening the rear track would free/loosen the car up. If I have stated incorrectly somewhere in my posts, please point it out so I can correct it.

Thanks & take care ! :thumbsup:

[Payton King]

I know it is hard to believe, but that is the first mistake I have ever made. LOL

I would also be curious as to what the tire temps are at the end of a run front to rear.

Sorry, we are getting so far off the original posted question.

[syborg tt]

I know it is hard to believe, but that is the first mistake I have ever made. LOL

I would also be curious as to what the tire temps are at the end of a run front to rear.

Sorry, we are getting so far off the original posted question.

Don't be sorry it's helping me learn

[71RS/SS396]

you not increase rear grip to balance the car instead of limiting front grip?

I believe both of you run the DSE rear...lower the panhard bar. I know it is not adjustable, but you could make it that way.

What is the track width on both cars? He could also increase track width in rear to tighten the car up...acording to Ron Sutton's teachings.
Payton, we have spent a ton of time working on different set-ups with the shocks and springs, we've made it pretty good. I like my car a little on the loose side but not on corner entry. Brian tried all of my shock and tire pressure settings and could never get his car as well balanced as mine.
Okay I am not a suspension guy and I don't claim to be either. However look at the new Z28 and it has 305's all the way around.

I've talked with the Lotus guys (Suspension & Chassis Engineer) for year about suspension and chassis design and they all agree more isn't always better. There is a balance and before you figure out the balance you have to know how to tune a suspension which I am willing to bet 99% have no clue how to actually do it.

I also talked with a couple guys at Ride-Tech at Sema and the subject of 295's all the way around came up and they thought it was a good idea and now you just have to figure out if all 4 tires should be the exact same height or should they be staggered. Lots to think about and I know there is a post from a couple years ago that I made that had some great information.

My future plans with my car is to run 295's on all 4 corners and spend a bunch of time tuning the suspension with someone that really understands how they work.

There are so many things to consider and I think it would be great if one of the experienced guys to chime on with suggestions as to what they think about the tire pressure, Spring rates, rebound, dampening, weight bias & so on as I really would like to learn as much as I can over the winter so I don't look like an idiot next year when we start to thrash on my camaro.
Marty, it will really depend on what is comfortable for YOU to drive. Different tires like different pressures, the Rivals seem to have more lateral grip at higher pressures and more forward/braking grip at lower pressures.