No, what I mean is the backspace remains the same for our application, no matter what the width is. If you run a 7" wide wheel you'll want 5.25" backspace. If you run an 8" wide wheel you'll want 5.25" backspace. If you run a 10" wheel, you'll want 5.25" backspace. This keeps the distance between the inside of the wheel and the suspension components the same no matter the width of the wheel.
Obviously if you keep the Backspace the same, the offset changes; and if you keep the offset the same, then the backspace changes.
Are you basing your logic on the particular Bogart wheel you are using? Because it does not apply to most wheels.
A 7" wheel with a 5.25" backspace equals to a 32mm offset. A 8" wheel with the same backspace is a 19mm offset. Although both the backspacing and offset play roles in fitment of the strut and caliper in most cases you do not need extreme measurements UNLESS the design of the wheel spokes do not allow caliper clearance. Which is why I asked if your measurements are based on your Welded R/T model drag wheels.
In any case to all reading this, before purchasing dedicated drag wheels I would ask the manufactuer if they can provide some sort of template to help determine what offset would be needed to clear the calipers.
Are you basing your logic on the particular Bogart wheel you are using? Because it does not apply to most wheels.
A 7" wheel with a 5.25" backspace equals to a 32mm offset. A 8" wheel with the same backspace is a 19mm offset. Although both the backspacing and offset play roles in fitment of the strut and caliper in most cases you do not need extreme measurements UNLESS the design of the wheel spokes do not allow caliper clearance. Which is why I asked if your measurements are based on your Welded R/T model drag wheels.
In any case to all reading this, before purchasing dedicated drag wheels I would ask the manufactuer if they can provide some sort of template to help determine what offset would be needed to clear the calipers.
You're still not getting what I'm saying.
No matter the width of the wheel (7, 8, 10, etc) The distance from the Wheel Mounting Surface to the Back Side of the wheel needs to remain the same for our cars. This does not change (unless you're trying to make the slicks stick out further than necessary). YES, the offset changes but the backspacing (distance from the Wheel Mounting Surface to the Back Side of the wheel) does not.
Hence, if you know the backspacing (which is what custom wheel manufactures like Bogart want) then you don't need to calculate the offset.
No matter the width of the wheel (7, 8, 10, etc) The distance from the Wheel Mounting Surface to the Back Side of the wheel needs to remain the same for our cars. This does not change (unless you're trying to make the slicks stick out further than necessary). YES, the offset changes but the backspacing (distance from the Wheel Mounting Surface to the Back Side of the wheel) does not.
Hence, if you know the backspacing (which is what custom wheel manufactures like Bogart want) then you don't need to calculate the offset.
And your not getting what I'M saying...
I've asked you to clarify if what you speak of is in regards to the Bogart wheels which then would make sense. Because if its not in regards to the Bogart wheels then you are wrong.
The backspacing DOES NOT have to remain the same on our cars for proper fitment. A perfect example is comparing the stock wheels backspacing of 5.25" to my 18x8.5 wheels which have a 6.25" backspace. They are not the same and fit fine.
In one of your previous posts you mentioned about needing to run a 5.25" backspacing on a 7 and 8 inch wide wheel. On the 7 inch, the offset translates into 32mm which although is slightly on the low side its within reason. But on the 8 inch the offset translates into 19mm which is WAY too low. We're talking about a wheel that will stick out way past the fender. A backspace of 5.75" on the 8 inch is more than acceptable and more within the proper range.
Comparing Street tires and Street wheels to Drag Slicks and Wheels is not going to work. They are two completely different animals.
On street tires I agree with you, there is more room to deepen the backspace and move the wheel inward. My 245's are 9.7" wide (section width) on 8" wheels, with about 8" of tread width. Which means the tires overhang the wheel by about 0.85" on each side. These are 8" wide wheels with a 35mm offset and are about as close to the struts as you'd want to go. And the backspace is about 5.75", which is deeper than stock.
However with slicks, there is no more room. I have about 3/8" to 1/2" between my coilover and the edge of the slick at the closest point, that's with the narrower 8" Hoosier slicks. With the M&H 8.5" slicks its is about 1/8" to 1/4" (the M&H's also have a considerably larger section width). There just simply isn't any more room to deepen the backspace. So the backspace must remain the same, as the wheel width increases (to accomodate larger slicks).
Here's some graphics to help explain the problem:
As you can see there isn't alot of room to start with between the slick and the strut. If you try to deepen the backspace then the slicks will start rubbing. The section width on the M&H 8.5x26 tires is 10.5" meaning they overhang the 8" wide wheels by 1.25" on each side.
You can only deepen the backspace so far before the tire starts rubbing on the strut. And when running slicks, it's even worse because of how wide the slicks are in relation to the wheel.
Will the exact specification of the Bogart wheels you have not rub the "stock" strut assembly (because they are obviously wider than aftermarket coilovers)?
I ran the Hoosier 26x8 slicks on these wheels with the stock struts, however, I had trimmed the overhang of the spring perch off (there's a thread w/ pictures in this forum).
I have been looking for slicks and the wheels to go with for my 2005 ACR.
I am worried about the fitment with the struts hitting them. None of my friends have ACRs so I have not been able to get any good info.
Those bogarts that the above link leads to looks good and If I went with such a good looking wheel I might as well get the set(skinnys) for the back.
Can anyone help me out with some recomendations for a wheel/tire set set up for drag racing slicks??
I have been looking for slicks and the wheels to go with for my 2005 ACR.
I am worried about the fitment with the struts hitting them. None of my friends have ACRs so I have not been able to get any good info.
Those bogarts that the above link leads to looks good and If I went with such a good looking wheel I might as well get the set(skinnys) for the back.
Can anyone help me out with some recomendations for a wheel/tire set set up for drag racing slicks??
I have been searching threads for days now talking to everyone I could get to listen about this issue. I have finally come up with what I want and what most people want to know. This is however totaly unrelated to this particular thread.
After speaking with John at M&H slicks a supporting vendor for the board I have come up with the perfect size for my application. As far as the slick size goes I am going with a 24.5x8.5x15. I will be putting these on 15x7 Kosei Silver rims.
If you go with a 26 inch tall rim you will have to go with a 6 inch wide slick to make it clear the stock perch. You can go to an 8 inch slick if you cut the perch to make for the clearance or you will have to switch to coilovers.
By the way John at M&H was very helpfull and I would recomend anyone with questions or looking to buy a slick call him. Or contact them. There is a link in supporting vendors and here is the email addy mhash@att.net or you can call him at 1-661-706-1576 .
How did you come up with those specs? Did you specifically order them like that or was that recommended to you by Weld? Have you mounted these wheels on the car with the slicks on?
How did you come up with those specs? Did you specifically order them like that or was that recommended to you by Weld? Have you mounted these wheels on the car with the slicks on?
yes thay r mounted.. nemo helped in makeing sure thay where going to fit.. also i think he had to use a spacer in the rear.. ill get pics up soon of the car.. for yall. also i run ipp's coilover and my slick r 26/8.5 mickey thomas. and rear r 24.5/3.5 mickey thomas.. weight of wheels r 6 lbs..
Last edited by smellmyface : 02-20-2006 at 04:46 PM.
yes thay r mounted.. nemo helped in makeing sure thay where going to fit.. also i think he had to use a spacer in the rear.. ill get pics up soon of the car.. for yall. also i run ipp's coilover and my slick r 26/8.5 mickey thomas. and rear r 24.5/3.5 mickey thomas..
I think when you said 5" backspace for the rears, I think you might be off a tad since the rears are only 3.5" wide.
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