I know there are wheel size threads here so go easy on me. i couldnt find what im looking for. Im installing a 4th gen rear end. I know the 4th gen is wider by 3/8 inch or so. I know that will make the tire stick out of the rear a bit. What im wondering is will that extra 3/8 in give clearance for more wheel if the back spacing is adjusted. I want to run old school centerlines. I found a pretty nice set that are 15x10 and a set that are 15x13. Im not sure where to find this information. Any and all help is appreciated guys. Also if it makes a difference i want to run as much tire as i can. I have 235/75 on it now and really like the fat tire look

 

Changing the axle doesn't increase tire capacity, just changes the offset needed.
A 4th gen axle is almost 2" wider on each side, not 3/8, not sure where you got that number from.
15x13 will never fit without backhalfing the car.
15x10 with 6.5 is ideal, but does require inner wheel well modifications.

 

I knew the axel was longer but I didn't know how much. I was just throwing a number out there. I appreciate the info. thanks man

 

The axle is 1-5/8" to 1¾" longer on each side.

It's REAL tough to get tires wider than about 315s in the wheel wells; that's all the space there is, between the LCA mount on the inside, and the fender lip on the outside. Axle length has nothing to do with that. All ya gotta do is make sure you get the right offset/backspacing to locate the tires accordingly.

 

I'm going to jump in here and hopefully will not highjack this thread. I, too, have a gen 4 reared and I have a set of Corvette wheels (1992) that we would like to use. It appears that the Vette wheels are front wheel drive offset. Any idea if these will work? Thanks.

 

Yes, they will. May need spacers on the front though, virtually for sure, probably around 1-3/4". Rears will likely fit fine.

 

I have found a 295/55/15 on a 15x10 is about all you can get under a camaro. 7.25 bs but 7.5 would be more ideal

but if you drag race you wont need any more tire than a 275 pro radial mickey. Cant get it done on that you have other issues. On the street you may like the street versions more

 

To be exact, the tire size I want to use is 275/40-17 on a 9.5" wide rim. Which is standard on my 92 Vette. Will these work on my 83 Camaro?

 

That's what I have on the rear.

 

How about the front?

 

I think I have 245/50/17 on the front but can't remember exactly.

 

About any of the stock Vette or 4th gen wheels will fit on the front, with the right spacers. Can't recall what tire size mine are either but they're stock (looked em up and bought em at tirerack.com) for about a 97 Vette, that being what my wheels are.

Which as mentioned, the right spacers are going to need to be about 1¾". You could maybe go with 2" if your car has bonked something on the front with the nose, and the fenders are warped outward and upward as a result like so many are, but since my fenders are straight, 2" was too wide.

 

will 315s fit without modification or would I have to add a tub?

 

Hard to say for absolutely sure. There's variation from one car to another, they're just simply not that precisely accurately consistent. It should though. My guess though, would be, anything more than that, no.

The inner limit is the place that the LCAs bolt to the "frame". Hard to move that without wholesale suspension alteration. Most of the rest of "The Car" is just a wad of sheet metal, basically tin-foil trim, and you can beat that into submission with a big enough hammer. But not that. It's not about "add a tub"; it's more like, COMPLETELY redefine the suspension, THEN put in a tub to keep the road debris out of the back seat. What a tub alters, makes no difference to the issue at hand, in and of itself.

The outer limit is the fender lip. Which of course, since it's not really "The Car", but rather only a piece of tin-foil trim hung randomly and loosely out in space somewhere, can be "adjusted" substantially, although it starts to look REAL STOOOOOPID past a certain point.

What justification is there for wanting more tire on there than that?

 

315 is a pretty wide wheel. I think that would be more than enough if it fit.

 

The LT and LS rears are slightly different lengths. I thought the difference was around 3/8" overall.

 

With offset LCA's you get some additional clearance. However, to Sofa's point, the next interference will be the side of your spring mount (wad of sheetmetal). You can cut that off and replace it with a plate that doesn't protrude towards the direction of the tire. I installed a tub so that I could have a more consistent inner diameter of the wheel well allowing me to tuck the rear tires under the fender lip. I measured extensively, and even with my mini tub, I am not sure I could aesthetically fit a 315 tire out back and not have it rub to some extent. You see lots of photos of guys running 3XX wide tires, but I bet the pictures are fooling you and the wheels don't "tuck under" as nicely as the pixels are showing you.

However, do to car to car variability (although I believe this to be very minimal) I have seen some guys running 315 + tires that seem to fit on an unaltered tub, making me scratch my head given the amount of time and money I have put into mine. Then again, that also lets me think that maybe they don't fit all that well as mentioned above.

 

I think 300mm-305mm is a big tire for a non race street car. once I finish my rear end install I will have to do some serious measuring and figure out what I need as far as width and backspacing to shove a big ole fat meat back there.

 

Not all 315 measure true! Goes for all sizes really. I’ve had two sets of 315s that had over an inch of tread width difference

my current 305/35/19’s are just tucked and very tight on the inside. Its a tall tire tho. Alot of inner well beating
but even that tire is only 12.1” section width. Its an old street radial 2 by mickey. The newer version is advertised at 12.9 width.