stock 91 z28 that has 145-50-16 all around. my back tires have little tread left and i need new tires. i wanted to get really wide tires in the back and keep the 245 50 in the front. my question is how wide can i go in the back without having to make mods to the car. 275-45-16? i have no idea

Why are you wanting to go to a large rear tire? Traction or looks?

295

both

Interested in this as well, id say somewhere round 295 too.

If your wheels are the stock 16x8 255-50-16 is the widest you should go.

That is a matter of OPINION.

I ran the BFG 295/50R16s on the stock 16 x 8s years ago, with zero rubbing, even lowered, on my 92 RS.

see the only problem is that i cant find anyone that sells them that big

I just told you though.....BFG.

BFG 295/50R16

From the tire ratings on those, I'd think you'd be better to go with a newer sticky compound tire in 255s or 245s. Might not look as... the look your going for, but they'd probably perform better.

I have had 17x11's in the rear with 315-35-17 and no rubbing as long as no one was in the rear, and it looked so go, it was just before I joined this web site back in the day, 17x9.5 and 17x11 had just came out...

What bs did you have on your wheels? 4th gen bs, with spacers? 4th gen rear end? Or inner fenderwell trimming?

I had pics on this site,back in 2002-2003, but when the server went down years ago they where lost, the rims where for my 87 IROC, they where Welds, It was back in 2001 wish I could remember the BS for you, I got them used at a used tire shop for $900 with tires, we tried them on I drove home no rubbing, not yet lowered, they said they where for a Chevy 454SS, the wheels where unilug style with a spin on center cap, that kept falling off going down the road. I did no fender trimming and a lot of work with a BFH and bump stop removal after lowering the car with the Sportline springs, but in stock form it never rubbed, looked killer, wish some one could find the pics I had, my laptop died a few weeks after the TGO website server went down so I lost the pics, I still know where the rims are, a friend of mine put them on his 69 El Camino and it looks BAD A$$, when I get home from IRAQ I will get the rim specs if he still has them.

I was more getting info for other readers of TGO, than for me, really. You had a stock 3rd gen rear end?

I already have my 11"/315s (7" bs), possibly going on today, If I can figure out the e-brake cable.

yea stock Alu. drummed rear from a 1987 Iroc, just, I have asked all my family if any one has any pics, and no one has any, well my sister did but her comp. crashed, like mine and lost them all. If thier is a way, I did have them on this site in 2002-2003 and you would be able to see how they fit, it blew every ones mind, no adapters, no BFH treatment, well untill I lowered it, then it was BFH all the way,and the sawzall to the bumpstops...454SS wheels fit 3rd gens, just have to be the uni 5 lug type,or just order them in 3rd gen's lug size, back spacing is all the same, trust me I looks bad a$$ and fit like a champ, no rubing up front with 275-40-17 up front and 315-35-17 out back, just dont lower it, or its time to BFH/Sawzall it up. Oh I just thought about it, I had NEW SHOCKS out back and struts up front, maybe it made the differance?? sorry I cant spell and dont have the iespeel.com stuff sorry..

yeah i think im gonna go with 255-50-16 bf goodrich gforce sport

http://www.tirerack.com/tires/tires....omCompare1=yes

They're a pretty good tire. Had them on my 16s and 17s. Not the best, but pretty good for the money.