Hello fellas. I have a protouring look going on on my 68firebird and was curious to know if i could possibly fit a set of 20x9.5 Torque Thrust II's in the rear without any major rubbing issues. If so what offset would look great? and for front i was thinking of going with a set of 18x8 or should i do 18x7.

NOTE: Front will be lowered with 2-3" drop coils AND 2" drop spindles and disc brake conversion on all 4 corners. REAR will be dropped with drop spindles as well

thank's i would really appreciate your help.

bump. anyone?

First impression, absolutely not a chance without at least mini-tubbing the car.

This guy here with a '69 worked hard to get the largest rims and tires he could on a stock FGF: He came up with 18 x 9 in the rear.

Wicked Bird

Detroit Speed and Engineering says they can get a 335 mm tire max in with their mini-tubs for 1st Gen F-bodies:

Detroit Speed Mini-Tubs

My first thought was "not a chance". But I didn't want to come across negatively.

If you do a search regarding "tire sizes", there have been many threads regarding this subject.

do you think perhaps the 20x8 would fit without having to tube the rear?

I did some more checking.

1) Our FAQ's section here also says 18 x 9 is the largest. It does not even deal with larger wheels. However it says a 5.5 inch backspacing

2) The guy with the cool '69 installed a customized Ford 9-inch rear in his car. I had forgotten. Because of that, he could use different backspacing than above (3.75 inch)

The Camaro types seem to be more into "wagon wheels". You can wade through this thread I found for info:

20 inch Wheels on Team Camaro

I believe somebody mentioned using 20 x 10 Foose wheels at the rear at the end of the thread.

i wonder if some of the first gen camaro's running 20's in rear with 8" width had to tube their rears..

this is the look i want:
http://www.dericksamsondesign.com/Articles%20Publications/Superrodjuly-07/SR_0707_67CAMARO_2.pdf

the stance is perfect

I see why they did'nt re-install the wheel well chrome. It would get peeled off with the first turn and road bump!

Looks like this guy on team camaro (last post) is running his camaro with 20x8.5" rear with 255/35/20 tires and a 5" back space

front 18x7 on 235/40/18 with 5.5" of back space BUT mentioned his tire rubs against the frame when turning sharp. and a narrower tire would do it

Please don't call it the "protouring look." Protouring is about function, so we put on larger rims, but only to clear larger brakes (and I don't know any runnimg 15" brakes). So most run 17s or 18s.

That large a rim requires a very short sidewall making it hard to "feel" the limits, and forget traction in a straight line, or powering out of a corner (hence the drifting crowd runs ultra short sidewalls). It's more like "proshow" or if you raise the car a few inches, it's a donk.

A 275/30R20 should fit on the rear with a 9.5" rim and 5.5" backspacing, but it will be tight.

A 2" stagger is too much stagger and look even more goofy. I'd suggest, if you really want to go that big, do a 18/19 combo. Max on the front would be a 245/40R18, with 275/35R19 on the rear. My real preference would be to do 18s all around though.

Think I'm gonna hurl.

I know you didnt ask for this , but my first answer is "WHY"?

imho those are way too big rims for a good look....of course we all build our cars the way we want ...but IF you ever want to sell it, you better save the stock wheels.

Eddie, you may want to check the PY forum on this.

that blew my Friday....

i've decided 20's are wayyy too big. So i'm just going to go ahead and get the 18x9.5 on the rear. the front and rear drop should make it look better all together.

FYI if you plan to drop the rear you'd best check your cross sections and heights first. Same with the front; turn the wheels full lock left and right, measure clearance to subframe and clearance to wheel lip, then correct for the new tire dimensions and wheel offset. On bumps, all bets are off.

The thing to keep in mind is that NONE OF THESE PEOPLE HAVE WHEELS THAT FIT THE CAR!

A$$holes spend millions of dollars on everyting else, claiming that the car ia perfect, and the a$$holes cannot turn the car because the wheels don't fit.

In other words, if you view proper steering as a requirement, you cannot even get small 15' on the car, and this was a done deal 25 or so years before the birth of this board--before any of the folks around here had any interst in these cars.

Telling it like it is...

So, if my rear tires don't fit properly into the fender wells, that means I am an a$sh0le?

I've certainly been call this before, and deservingly so but, never due to the size of my rims and tires.

Ya learn somethin new everyday...

Who are "these people" that you are referring too?


Again, who are "these people?" Do you have proof they don't fit? What size tires, what width rims, what backspacing are "these people" using? Is the car height lowered? Disc brakes or drums? Has the camber gain stock or corrected for negative camber? Are the alignment settings stock or modified, and to what new specs? Is the frame stock or aftermarket and if so, which brand?

I wouldn't call 15' rims small. It wouldn't even fit through my garage door. I don't even think an earth mover as 15' tires, let alone rims. Largest I could find are 140.9" which is less than 12'.

not so sure thats right Amervo, Jim has had his since new, I had a used one in 1969...thats 40 yrs ago...