right now im running 16x8 wheels with the 26x11.5 et streets out back... i just ordered those centerline skinnies for the fron so i wanna get some centerline wheels for the rear...

im wondering whats the BIGGEST wheel/tires combo that can be run on an lt1? i dont mind having to pound on the fenders just a lil but i dont really plan on doing any tubbing anytime soon so lets just keep it at that also which size wheel is the best as far as 15's 16's etc..

thnx

 

15" is better for the track. More wrinkle in the sidewall.

You can fit 28" diameter tires in the back, but be sure you look at the manufacturer's published diameter, because not all 28" tires are actually 28.0" diameter. I've run 28x11.5-15 QTP's on 15x10 Weld Pro-Stars, and there was very little problem with fitting them in the fenders, until I went over 125MPH trap speeds. Then the tires were growing enough to start hitting the sheetmetal at the front of the wheel opening. I had to move the axle back about 1/4" to make more clearance. The QTP's were 28.0" diameter.

Now that I've switched to 28x10.5-15W ET Drags, which are shown as 28.1" diameter, I've had to hammer the crap out of the inner fenders, and cut more than 1" off the rubber bumper cover to keep it from rubbing. And that's just standing still... the car hasn't been to the track yet with the new tires, so they might still require a bit more hammering and cutting.

 

nice... so wait with 10.5's they rubbed... but with the 11.5's they didnt?? or is it just because the 28's were 28.1??? is that what the issue was?? why did you switch to a lower size?? 11.5 to 10.5??

which 15x10's are you using?? what size backspacing?? this highest ive found is 15x10 5in backspace... is that the one i wanna go with??

btw what wheel/tire combo do u have on trailer queen??

 

A 28x11.5-15 Hoosier QTP:

Diameter - 28.0"
Section Width - 11.2"
Tread Width - 10.0"

28x10.5-15W M/T ET Drag (maybe you missed the "W".... that is for "W-I-D-E"..... ) :

Diameter - 28.1"
Section width - 13.1"
Tread Width - 10.9"

So... slightly softer compound, wider tread.... more traction.

Wheels are Weld Pro-Star 15x10 with 7.5" Backspace. You might be able to get away with a 6.5" backspace, but it would move the tires 1" further out on each side than mine are. No way you could run with 5" BS, unless you wanted to make sure you had somewhere to sit between passes...... .

You won't find the 7.5" BS in any catalogs, like JEG's or Summit, but Weld does show them on their website, and if you get the part # off the website, you can enter it in the Summit online catalog and it will show up.

Weld Pro-Star and Draglites in 15" sizes require longer studs, and grinding the rear calipers. Not sure if Centerline makes a 7.5" BS, but I know a friend of mine run the 15W's on his 97 SS convert with the AutoDrags.

The ET Drags, being almost 2" wider, and slightly larger in diameter caused a problem with the inner fender (width) and also with the bumper cover (diameter). I need to actually measure them, because they seem at least 1" larger than the QTP's. If you have "rod end" LCA's you will have less problems, because the axle can not move forward under heavy load, like it can with my poly bushing LCA's.

The "trailer queen" shot is with the 28x10.5-15W ET Drags/

Here is the same picture with the 15x11.5-15 QTPs:

QTP's

and several more on this page:

QTP's

There are more pic's with the ET Streets on this page:

ET Streets

 

Actually we have a TA that with minor trimming on the inside of the back ground effect we run a 28X10.5 True Hoosier Drag with a Pro Star 15X10 with 7in backspacing with no problems what so ever.

I know of a few local 4th gens that are now running a 29X11.5 on 2 camaros and one firebird with minor trimming.

 

There must be no clearance between the tire and bumper cover/ fender lip with a 29" tire. These things grow at speed, and as far as I'm concerned they should not rub, as a safety measure.

Rich Krause

 

nice thanks man... so lets say i plan to go with the

weld pro-stars 15x10 7.5in backspacing and a set of et streets size 28x11.5x15 will those work ok then??? also would i still need longer studs with these wheels? wouldnt the 7.5in backspacing equal out with the stock studs?

thanks man

 

A buddy of mine put 29.5's on a 30th SS and it required major bodywork. I've also seen some posts by an individual on the Drag Racing forum who couldn't even fit the 28x11.5 QTP's without cutting away the complete jounce bumper and 6" of sheet metal above it.

29.5" tire on a 30th SS convert

What you find after you work on enough of these things is that THERE IS A HUGE VARIATION FROM CAR TO CAR. When I show pictures of my 315/35-17 Drag Radials, and the inner fender hammer work that was required with the 17X11 GS offset wheels, people tell me I'm nuts, their's went on without doing a single thing.... same wheels, same tires. There is an unexplainable variation among the cars, and it can't be traced to Camaro vs. Firebird, etc. I think if you look at the pictures I posted, you can see that there is no way a 28" tire would have fit in the stock Formula wheel wells, with the SPECIFIC configuration I have. I'm not convinced that the Strange 12-bolt width might come into play here. Also mentioned the the poly LCA bushings become a factor. Mine were fine until trap speeds went over 125mph. Above that, they grew too much.

And we had the exact same problems with 28x10.5-15W's on the 30th SS covnert.... we spent an awful lot of time with a 3# hammer.... and the converts have a lot more meat behind the inner fender sheet metal than the coupes. He was running rod-end LCA's and was able to get away without moving the axle, even at 155mph trap speeds.

The 28x11.5-15 ET Streets are only 27.6" diameter, and 11.1" sidewall width, so you shouldn't have a problem with those.

You need longer studs. The backspace won't "equal out" anything, and backspace has absolutely nothing to do with the stud length. The Welds have a center hub disc that is more than 1" thick. You need to use "extra long shank mag style lugs" with washers. NHRA requires that the stud engage the threads "IN THE HEX PORTION OF THE LUG" by at least "one diameter".... that means the studs have to be at least 1/2" into the "hex" portion of the nut. They give you no credit for the 1" that engages the lugs in the "shank". I run 3" studs in the back, 2.67" studs in the front.

 

like injuneer i too am running the 28x10.5x15" w's of course. 28.2" dia. and they grow upwards of 1.5" 's.

yes the jounce bumper and complete bracket is all gone, trimmed in front of and behind the wheels. but i need the tire to have the mph i want. so a trimming we did go, lol!!!!!

7.5" back space is the way to go! stick with the 10.5"W's, just my .02 . i don't know how much fitting would be required for a 11.5" tire. i also had to pound on the inside towards the front of each rear wheel, in the well. i hope that makes sense.

only 2 weeks from now i will be spraying the old girl once again! boy do i ever look forward to that!!!!!!!!