Has anyone tried them on an HHR yet?

yep 255/50/16 on factory steals. Just clears

How much did it improve your 60'? I'm thinking of downsizing to 17's so I can get the 225's that BFG sells. But then I wonder what the difference would be between that and using a wider tire on my stock rim in a fairly sticky compound. 235R18 or 245 even. Maybe Falken Azenis. What do you think?

I only went one night and it was a crap one at that....sooooo I really cant say, but what I can tell you is the smaller the wheel and less weight you can spin the better every thing will be.....on my old cobalt ss I seen a 10hp gain going from the stock heavy 18 to light weight 17 (9 pounds lighter a piece.)

Right. Unsprung weight ftl. I'm trying to find the best compromise between looks and performance, and the 18's look SO hot.... thanks for your reply.

Just get a couple for the fronts on track day and run the 18 the rest of the time. If you need a little more sticky for every day use just buy a better tire for the 18's.

I think that's what I'll do, and go wider too.

I have been thinking 245/40/18 for tires....wonder if any one has tried them.

I have been thinking 245/40/18 for tires....wonder if any one has tried them.

that's exactly what i'm planning when it comes time to replace my tires. get a set of BFG KDWs or something.

that's exactly what i'm planning when it comes time to replace my tires. get a set of BFG KDWs or something.

+1, but I may go wider front than back. I did it on my Sentra with great success, the point being that I didn't need the extra grip in back, therefore I didn't want the extra weight and rolling resistance. I was running 235/35/18's in the front and 225/40/R18's in the back. No one ever noticed, but it sure did help off the line. Thoughts?

+1, but I may go wider front than back. I did it on my Sentra with great success, the point being that I didn't need the extra grip in back, therefore I didn't want the extra weight and rolling resistance. I was running 235/35/18's in the front and 225/40/R18's in the back. No one ever noticed, but it sure did help off the line. Thoughts?

hell of a good idea IMO. in fact, i think i'll "borrow" the idea come new tire time haha. keep the stock size out back and go for the 245/40R18 out front. should keep the diameters close enough to not goof anything up (is there anything that could get goofed up by this? ABS or TCS or something?), and give us some good grip out front, while keeping the rolling resistance down out back, maybe even step the rear down to a 215? i suppose i have some time to kill before i HAVE to make that decision. see how other people's experiments pan out, as far as fitting the larger sizes, running different sizes front to back, etc. if no one else has any problems, i'm all over it. i've only got 7400 miles, and i've heard these tires are good for about 30K or so.

You can vary the aspect ratio (I think that's the right term) so that you get as close to the same diameter as possible between the tires. There are tire size calculators everywhere for you to fool around with. The 225's in the rear were still one size up on the Sentra, and the 235's were plus two. I like the way it made the sidewalls bulge out in the front. Looked mean and muscular as hell.

I don't know if I'd go with 245's and 215's. Having that much difference in contact patch might make you oversteer if you got aggressive in the twisties. That, and it'd be really obvious to the casual observer. That's almost an inch and a half more meat in the front, so you'd definitely have the drag racer look.

But it's not like your ride is a sleeper anymore anyway with the Wilwoods. ;)

haha, fair enough! :lol: we shall see. might just go 245 front and 225 rear. as i said, i've got time to figure it out.

the 245/40/18 are pretty close to the same height as the stock 225/45

the 245/40/18 are pretty close to the same height as the stock 225/45

thats precisely why i'm looking at that size, it's almost identical. such a slight discrepancy in size front to rear shouldn't cause a hassle with TCS or ABS or anything, right? can a discrepancy cause trouble for any of those types of systems? like say you've got a fairly significant diameter difference, say like 1/2", are those systems configured in such a way it could cause problems? does anyone know?

Stop being a wuss and be the guinea pig. If nothing breaks, I'll do it too. :lol:

FWIW,Pontiac did this very thing on the Bonneville GXP a couple of years back.

Stop being a wuss and be the guinea pig. If nothing breaks, I'll do it too. :lol:

jerk lol :lol: if i had the money to do it now, i would, believe me haha. you get to guinnea pig this one, i bought the expensive (but oh so SEXY) brakes, remember?