bigj85z-28

I would like to run a 15x8 prostar with a 28x10.5 tire in the rear and a 15x3.5 skinny on the front. Whats the correct backspacing for this on an 82 camaro? My buddy also wants to run the same combo on his 74 camaro. Whats the backspacing for those too? Are they the same width? Thanks so much for your help guys.

-Justin

mw66nova

iTrader: (13)

for your car, run a 4.5" backspacing, it will put it right inside the lip. looks good imho

for your buddies car, run a 3.5" backspacing.

bigj85z-28

Thanks for the info man... is that for both the front and the rear wheel spacing?

Nice to see someone else with a bored 305...were a rare breed.

mw66nova

iTrader: (13)

front only comes in one backspacing and will work fine. what i posted was for rear only.

what's your car running? my desperetly need some head work/cam/double pumper carb, but so far i have managed some 13.7's.

bigj85z-28

Unfortunately I have never ran it at the track with the new cam... it also has a 3.23 non posi rear now. Before the comp cam, with a dirty paper filter, crappy summit muffler, and street tires, and the 4spd with a badly slipping clutch it ran a 10.23 in the 8th! I was rolling on the floor laughing at that performance.

Now, it has the KN filter, comp 280H cam, a 2 chamber flow, and its getting a TH-350 in it. Ive never really gotten to drive the car much with this setup. The clutch went 2 weeks after the cam was in. It is a beast from a roll though. The heads are l98's that have had a lil work done to run the springs that can handle that lift... and a lil port work. nothing special by any means. Carb is an edelbrock 660 jetted as fat as possible. With a posi and slicks... I can easily see mid 12's. Desktop dyno shows about 350hp with this setup. and it honestly felt like that when she ran.

once the trans is in.. ill probably end up trying to get rid of it and movin on to another project... I have a sweet 406 with 2 stages of spray thats looking for a home... 750hp... will make just about anything fun though...haha. Thanks for the help again man.

-Justin

mw66nova

iTrader: (13)

with the l98 heads, are you using the aluminum 113 castings from a corvette or are you using the iron castings from a camaro? i'd think the larger combustion chamber of the iron ones would decrease power.

bigj85z-28

theyre just camaro castings. The pistons are 10.5:1 hypereutectics... and im honestly not sure what the chamber sizes nor compression ratio is in the car now...i just figured they had to be better than the stock 305 heads from 82.

mw66nova

iTrader: (13)

the stock heads are the 416 castings, which are actually, really good with a little work. but with 10.5:1 pistons and the 64cc combustion chamber of the current head, you still pretty good with around 9.5:1, which is what i am running with my bonestock 416...

1BADRZ28

iTrader: (2)

you can also run a 28x11.5x15 hoosier quick time pro with that backspacing. I had to massage the front part of the inner fender though. It was no big deal and you can't even tell I did it after I painted it black. That tire looks good on the back. Hopefully you got the goods to need that size and it doesn't hang out the fender lip.

likeenz24

iTrader: (2)

5.5 backspacing on rear wheels is a good choice also..it tucks the tire inside the rear quarter nicely....might have to massage the front part of the inner fender (which is no big deal)

phoenix305

How did you get a 311 cid? I'd like to see your 305 run a mid 12. Those heads are no better than stock if they are the iron castings. I'm not trying to make you mad i'm in the same boat as you ( bored 305). Let us know if you break into the 12's cause i'll have to copy your combo.

AutoRoc

iTrader: (1)

I did 15X8" Draglights with 4.5" BS and the normal 3/5" up front.

So far I have tried 26X10.5" ET Streets which are too skinny and now I did 28X11.5" ET Streets which look great on the rim and under the car. Not anywhere close to sticking out from the fender BUT...I wouldn't run a true 10.5" slick/Et Drag on an 8" rim. Seems too wide. The 11.5" Et street only has about a 9" tread width, where a 10.5" Slick has just that...10.5" of tread. I'd run a 10" wide rim if I did that. and more BS.

Oh! and the 28X11.5" ET Street is really only 27.3" tall, not 28"

I got a 12.80 @ 110mph proven combo recipe for a stock long block 305 if you want it. probably good for mid 12's with tuning.

Goodluck!

bigj85z-28

Thanks for all the input guys... this is really going to help me out with my decision. As for the comment about running 12's, I did forget to mention that fact that my car has no interior whatsoever and is very much gutted. Its been on a pretty good diet. And from what I hear the 82 is a light year. Im hoping for mid 12's, but if theres issues with that, theres always a powershot system in the garage. Thanks again for the help.

83 Crossfire TA

iTrader: (2)

5” will tuck them under the fenders, 4.5” will put them right even with the sides of the fenders. You’ll need to mess with the outer fender lips with the 4.5 and a tire bigger then roughly a 275/60/15, where they’ll tuck right in with the 5”.

On the second gen use ˝” less backspacing for the same look. If going with a really wide tires you may need a little less backspacing since things start getting tight with the exhuast on the inside pretty quickly

88IROC350TPI

28x10.50" ET Drags with 15x8 5.5" BS ...tuck in absolutely perfect. Had to beat the crap outta the front part of the wheel wells.