Minimum side clearance on slicks?

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Cope

Cope

Fusing with fire
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My buddy from Hitman racing came over today to seem my mini tubs.
He took one look and said "Nope, that ain't gonna work"

He thinks on launch when the car twists its gonna ketch the sidewall on the inner fender and outer fender lip, destroying the tire and my quarter.

These guys build serious race cars and know what they're talking about.
He says cut the frame and make more room now before I shorten the axle, or hurt my car, my self or some poor bystander.

He want me to cut 1 1/4 inch out of the frame giving me 2 1/8" on each side
At this point I may as well just start over and back half the dam car... he's a good friend and some one I fully trust when it comes to what works, what's safe, what's not and what just may get you killed...

The only good news he had was that he will lend me his axle jig so I dont have to pay to get mine done...



I got about one inch on each side of the tire. What do you think, not enough?
 
Hey, if you trust him then follow his judgement.

I drag race my 408 stroker Dart on slicks with Cal-Tracs @ about 1/4 inch of fender clearance. Meaning you have considerably more then I do. Doesn't mean I am right, just means I do it with my set up.
IMG_8849.jpg
 
An inch on each side isn't enough? Plenty of cars have that or a little less and never rub.

Is this friend a drag racer, or circle track?
 
He's a drag racer but he is running almost 1,600 HP so maybe that's why he want so much room?
 
Yeah, one of his concerns was if the car goes sideways at high RPM.

I guess this is one of those posts where I'm just looking for the answer I want when I already know the answer I dont like..

Cut it all out and start over....
 
I'd be happy with the static clearance you have. During hard acceleration (and spinning), Slicks get taller and narrower.
 
harrisonm said:
I'd be happy with the static clearance you have. During hard acceleration (and spinning), Slicks get taller and narrower.
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I think yes under acceleration they get taller and skinnier but I believe what the Builder or his friend was saying is when you drop off the throttle they sponge down and it gets a little sideways now they're fat soft and stretching sideways in the wall if it gets left or right out of control a little bit? Now this is just what I'm thinking in my head.
 
j par said:
I think yes under acceleration they get taller and skinnier but I believe what the Builder or his friend was saying is when you drop off the throttle they sponge down and it gets a little sideways now they're fat soft and stretching sideways in the wall if it gets left or right out of control a little bit? Now this is just what I'm thinking in my head.
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I do see what you are saying, but will they get any 'fatter' during deceleration than they are when static? During deceleration, there is more weight on the nose.
 
harrisonm said:
I do see what you are saying, but will they get any 'fatter' during deceleration than they are when static? During deceleration, there is more weight on the nose.
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I guess because I have leaf springs and my car raises under acceleration and kind of drops it's weight under decelerating. When I hit the brakes it seems like the weight rolls forward and off the back a bit. I don't know if you're supposed to accelerate decelerate hit the brakes when things get all out of whack on one of those 9 second runs? I think the suggestion that his friend was making- when you're trying to real some nasty happenin's back in that's not when you want a tire to go down!?
 
It’s all good while everything goes to plan! I think your clearance will be fine as long as everything hooks up well but if it all gets out of shape and those big *** tyres start to wobble then you risk tearing up you nice clean panels and shiny paint.

I’d be taking the advice and adding extra clearance while you can (do it once, do it right).

Cheers
Anthony

Cope said:
My buddy from Hitman racing came over today to seem my mini tubs.
He took one look and said "Nope, that ain't gonna work"

He thinks on launch when the car twists its gonna ketch the sidewall on the inner fender and outer fender lip, destroying the tire and my quarter.

These guys build serious race cars and know what they're talking about.
He says cut the frame and make more room now before I shorten the axle, or hurt my car, my self or some poor bystander.

He want me to cut 1 1/4 inch out of the frame giving me 2 1/8" on each side
At this point I may as well just start over and back half the dam car... he's a good friend and some one I fully trust when it comes to what works, what's safe, what's not and what just may get you killed...

The only good news he had was that he will lend me his axle jig so I dont have to pay to get mine done...



I got about one inch on each side of the tire. What do you think, not enough?
Click to expand...
 
Horse power ,tire size, and torque multiple, come into big effectively, here ...Your asking the question ( s) ,here ..
Dyno the engine first,see the peaks between peak torque, and horsepower peaks... .finding the spread, will set this... Ask lots of questions...
 
Cope said:
My buddy from Hitman racing came over today to seem my mini tubs.
He took one look and said "Nope, that ain't gonna work"

He thinks on launch when the car twists its gonna ketch the sidewall on the inner fender and outer fender lip, destroying the tire and my quarter.

These guys build serious race cars and know what they're talking about.
He says cut the frame and make more room now before I shorten the axle, or hurt my car, my self or some poor bystander.

He want me to cut 1 1/4 inch out of the frame giving me 2 1/8" on each side
At this point I may as well just start over and back half the dam car... he's a good friend and some one I fully trust when it comes to what works, what's safe, what's not and what just may get you killed...

The only good news he had was that he will lend me his axle jig so I dont have to pay to get mine done...



I got about one inch on each side of the tire. What do you think, not enough?
Click to expand...

I ain`t got that much on my drag radials for the street, they just barely touch on an off camber turn Inside, have about 1" on the outside /never touches. I know a lady that has a 10 second 340 barracuda that has a 1/2"to the springs w/10" slicks and she doesn`t have a problem.
Probly depends on how much squirm ur gonna have ! Sway bar, rear end locator, 1600 h.p. ??
 
first question is what tire are you running, Im using drag radials and they don't grow like a Bias ply also what kinda power are we talking 500? 800? 1200? One inch sounds like plenty to me I have about 1/4 inch on the inside with drag radials 800HP car.

LETS SEE SOME PICS PLEASE :lol:
 
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Cope said:
These guys build serious race cars and know what they're talking about.
Click to expand...

Cope said:
I guess this is one of those posts where I'm just looking for the answer I want when I already know the answer I dont like..
Click to expand...

Allow me to put things in perspective for you, as if you didn't already realize it.:D
 
So by these standards we should all be mini tubbing just for what we have now let alone putting a seriously big tire under there?
I think there's many levels of cars and the amounts they are used and the amounts of risk people are willing to take with them. For instance your weekend warrior with four or five maybe six hundred horsepower can probably get away with lower clearances on an every other weekend basis.
On the other hand when you're talking a career racer who races daily with 1600 horsepower or more they are are in danger way more often and are taking way more precautions.
Safety is their number one concerne when they get to pull the trigger on 1600 horses everyday no problem.
 
I call BS. I run slicks with 1/2" maybe and I run them on the street. They scrub slightly on tight 90 degree turns or where the ground gets really uneven where the chassis has to articulate.

They definitely don't scrub on launch and if it gets sideways at drag strip speeds your done anyway half the time.

With stock springs you'll gain clearance at launch as seen below.

60391970-DSC07017.jpg


660ft June 14th 2015.jpg
 
If you can fit your fingers between the tire and fender/chassis then you're fine (roughly 3/4"-1" ish). This was my rule of thumb when I built my car, and it works just fine.
 
One thing worth mentioning that no one has touched on is making sure there are no sharp edges anywhere in your wheel well.
 
Rocco hit the nail on the head, "no sharp edges". My 10 second Demon running 29.5 x 10.5 x 15 has between 1/2" & 5/8" left & right respectively. I've been running it that way for about 10 years.
 
Them are some big tire. Think about that slow mo video.
Think about the play in the leaf spring/ shackle and then thing about that small end play in you axle......they could all add up to a problem.
My tires are way smaller than yours. have a finger width between the spring clamp and side wall of slicks.
has never rubbed.
wheel lip is above the slick.

Honestly, i would have to suggest you read post 15 again.:steering:
 
Do it right the first time, save money in the long run when you go bigger tire, We are always looking for more power and will be in need of a BIGGER tire. I've spent time and tons of money over the years redoing stuff.
 
fishmens67 said:
Do it right the first time, save money in the long run when you go bigger tire, We are always looking for more power and will be in need of a BIGGER tire. I've spent time and tons of money over the years redoing stuff.
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No one here needs more than a 10.50 slick. No one.

Small tire car now run over 200mph, run sub 1 second 60ft times and can have HP in the thousands.
 
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