wastintime

Hey everyone,
Well, pretty much all of our budget was moved from the Camaro into the Sonic. Both of which are going to be in the DC Auto Show in the GM display, btw. And both are getting a whole new vinyl scheme!

So, having our wheel budget cut by 75% we came up with the best solution available. 18x10 fronts running 285s or 295s and 19x10.5 rears running 305s or 315s in for a street tire/OLOA setup and it looks like we may have to run either a square 295 or 305 setup in race tires... possibly a 295/315 setup if we run one specific compound tire... we'll see though. I'll take some more pictures tomorrow in the sunlight, and obviously we haven't repainted them yet (the roll bar is getting welded in next week and painted fluorescent green to match our vinyl scheme, and we're painting the wheels to match). I figured I'd throw some pictures up anyway though. Partially because I'm just really happy they fit.

I'd heard a lot of griping about putting BMW wheels on Camaros, and how the offsets don't work at all, but they really fit well! The car was clearly designed with a 20" wheel in mind and as you go down in diameter you begin to run into clearance issues with the emergency brake cables (although we may just pull those out), and the front uprights. So you end up needing the BMW offsets anyway. Our fronts fit almost perfectly, and the rears are only a bit more to the outside. Actually the right rear fits better than the left rear. Lol, we used to see that on 911s all the time. Bodies don't always sit perfectly straight on the frame...


As you can see we had to machine the front uprights so the 18"s would fit. There's a knuckle for adjusting camber on whatever other car GM puts this upright onto, but it serves no purpose on the Camaro, so we just lost some weight in aluminum. Ground them down this afternoon and just finished testing the range of motion on the fronts... looks like we've got enough clearance to run a 295/315 setup if we need or want to.



Fronts: Tire Rack Motorsports TR-1M 18x10s with 285/35/18s



Rears: BBS CH-R 19x10.5s with 305/30/19s



And the whole picture:




Lol, it looks like the car is sitting up really high, but it's about 2.7" lower than stock... I'm hoping when we get the JRZs installed it'll help the stance some, but we may have to just deal with the fender gap. I don't know that we can lower the car much more and have it working for OLOA. Probably going to roll the fenders tomorrow, that should help the look a little.

wastintime

Figured I'd throw some better pics up... completely forgot to take any while the sun was up... or on the good camera, lol, but...







And the new race seats went in today too!

JasonD

Really doesn't look bad at all. In fact, looks pretty good. I know someone else who has smaller diameter wheels on their car, and it is very surprising because they don't appear smaller unless you really take a sharp look at it.

wastintime

Yeah, I think it looked better yesterday after the suspension settled some. I think if we'd put taller tires on them it would look even better, but we picked tire sizes purely on tread width and performance. The wheels look pretty good on the car too, even though they're completely different styles on each axle. I don't usually like having drastically different weight wheels on different ends of the car either, but in this case I think it's the right choice. The fronts are like 12lbs lighter than stock, each. So that combined with the 50mm wider tires should really help keep the brakes cooler (which has been a BIG problem) and working more efficiently. Although the brake ducts going in next weekend will probably do more for cooling them. The rears are only about 7lbs lighter than stock each... but that still helps with rotating mass and I'm sure improves acceleration. In fact... we've basically shortened all of our gear ratios with this tire diameter, so, in theory we really should have improved our overall acceleration.

2010_5thgen

so those wheels are from tire rack made for a BMW M3 right? i was wondering about this. 18x10 front and 18x11 rear? and all that was needed was the knuckle shaved off the front uprights? hmmm. i need a set of track wheels that i dont mind F'ing up. i was thinking 19's though.

wastintime

You also need the hubcentric rings, but TR can set those into the wheels for you and ship the correct lug nuts (as opposed to bolts for a BMW), but for actual racing we'll probably run Porsche race lugs (same thread M14x1.5). We're running 18x10 Fronts and 19x10.5 rears... there really is no 19x11 that is under $1,000 so over 2 sets of wheels we saved about $2,400 and it doesn't really affect our tire size choices, without a 12" wheel we weren't going to be running a 335. A 19x10 vs. 18x10 = $1,200 over two sets of wheels, so it was a no brainer to go with the 18s when there are plenty of tire combinations that work.

The other thing I might suggest is talking to Baer Connard at D-Force wheels, they might have something that works and might be a middle of the road price. They make a ton of BMW wheels, and as you can see it's really easy to make BMW wheels work, and the offsets aren't bad at all, if someone went with tires narrower than 305s they might not even stick out of the fender at all, and we're running like no camber in the rear right now either.

a 19x10 front probably wouldn't even need the knuckle shaved off because it would be 1/2" higher at the top so it wouldn't be touching. Again, going to 18s was purely for cost... and it also worked out well that the 18s were almost 10lbs lighter than the BBS 19s so... all around it's a really good thing.

wastintime

btw, by same thread, I did not mean Porsche and BMW have the same thread pitch, the Camaro and Porsches have the same thread pitch... which is nice because I have a ton of those lug nuts laying around. So you do need to specify that if you order them.

2010_5thgen

hmmm. the only issue i would run into with going from a 20" street wheel to a 19 or 18" track wheel, is id need a new alignment and camber adjustment every time i take the car out.......

wastintime

Why do you say that? I mean, the wheel/tire combo is not going to affect your toe, at least not to any measurable degree. Changing wheels doesn't affect the direction the hub is pointed in. So you don't need an alignment beyond camber. If you mean you'd want to be changing camber from a street to track setting, that is something different than needing to change it simply by putting different wheels on. The difference in camber will be incredibly negligible going from a 20 to a 19, although it's really more about tire diameter than wheel diameter. slightly more pronounced going to an 18, but you also have to remember, as you're decreasing the overall diameter of the tire you're lowering the ride height of your car and increasing the amount of negative camber you have... which is a good thing for the track, but again it's very negligible, and while depending on the suspension configuration, camber can affect toe, a negligible change in camber is going to make an even more negligible change in toe.

I think when we checked our alignment the rear hadn't changed at all, literally not by .1 degrees on anything, and the front may have had like .1 degrees of extra camber. Now the downside of running a shorter tire is you maintain your camber setting less through a turn, because the sidewall is less flexible and the tire is less likely to distort to a trapezoidal shape and maintain it's contact patch (that's why formula cars run such tall tires), but you gain a crisper initial turn-in. Of course, there's only so much camber you can run on a street tire anyway before you're overheating and/or wearing just the inside of it. Now if you're running r-comps, your alignment changes drastically and I can't imagine wanting to run the same street/track alignment.

wastintime

Now, having said that... I just realized, the hankooks we had on the car were a smaller diameter than the OEM pirellis and that's what we did the alignment on... so you might see a bigger change going from OEM to the sizes we put on the car vs. having a step in the middle. I think the OEM tires are 28.9" tall and we're at ~26.3" so we've lost ~1.25" of ride height just to tire diameter changes.

The only other issue you'll run into is having to remember the speedometer is no longer accurate, and/or retune it. But I seriously wouldn't even give two thoughts to the alignment changes... just figure out which alignment is more important to you, street or track, set it and forget it. It's not like you're competing and need the perfect setup for the perfect lap time.

Inferno X

Don't look bad at all. I bet u saved a lot of weight compared to stock SS rims. Plus R compound tires are cheaper in 18" sizes than 20".

wastintime

Exactly. In fact decent sized R comps simply don't exist in 20". 18" has the most variety of sizes and 19" has some fairly wide choices for the rear which is why we went with a 19" rear.

2010_5thgen

i object! lol the toyo R888 is a great tire that comes in a 20".you can get a 275 and a 315...which happens to be what im running now and what id like to switch to after seeing how these nittos do.

wastintime

Well, fair enough... lol, but the RA-1 doesn't exist above 18" and that's infinitely better in the rain compared to the R888, not to mention Hoosiers and Hoosier Wets.

Btw, D Force wheels, is one of our sponsors and is providing us with wheels for the Sonic race car (which we're picking up the stock car tonight), may or may not be coming out with some pretty cool wheels for the Camaro in 2012...

2010_5thgen

you guys arent looking for any drivers, are you?