robertbartsch

This weekend I put 315s on all four corners and took it out for a test drive.

The wheels (17x11x35 front, and 17,11x50 rear), bolted right up. The car has HD Beilstiens, stock 1LE SS springs, Samie bars x 2, adj PHB, LCA.

I drove the car +100 for a brief time over a couple of twistie back roads and drove 55 on the highway for 60 miles.

All-in-all, this was a VERY good mod; one of the best I have done so far!

Pictures of the ride are posted on the "wheels and tires" section.

z28bryan

iTrader: (7)

Cool. What kind of tires are you on and what sizes?

Where did you find the 36mm wheels? Did you use spacers or use different wheel studs? I use spacers and longer studs and it worries me slightly, but I don't know if anyone has had any problems with it.

robertbartsch

I did not use spacers; just bolted the wheels on.

Tires = Verdestein 315x17x35

The tires have more of a rounded shoulder than others I beleive; no rubbing - period!

The wheels are ZR1 Factory Reproduction from TomZwheels ---->

They have these wheels in both 50MM and 36 MM offset in their inventory; it took only 5 business days for the shipping from California to NY.

Anyway, I bought the rear set on 50MM wheels first. I tried to mount them on the front - no deal - the rims rubbed bad on the spindle. I researched some threads in the road racing forum and the guys said I could use 36mm offset wheels on the front without spacers or BFH. (I think the older Vettes used 36MM spacing on the rear - so this wheel combination 50mm and 36mm is readily available.)

Surprisingly, there is a ton of room in the front. I can swing the wheels 100% right and 100% left with no rubbing issues.

The more I look at the car from the front, the more I beleive GM should have done this at the factory.

The cornering is an UNBELEIVABLE improvement over 275s! I threw this car into sharp corners at 90mph and the tires did not even squeel!

z28bryan

iTrader: (7)

I didn't know that Tomz had 36mm fronts.. I wonder if that's new or if I should have just asked? Those I think would stick out a little more than they do now, but you wouldn't need to grind the spindle nub and could run in ESP legally.

I use 315 wide 555r tires all around. In normal weather, they ride great. In wet weather though, I find the wheel likes to pull in certain directions on me.

robertbartsch

Yeh, I suppose if you use spacers and longer studs you have more options for wheels (e.g., use 50mm x 4 which are available in many styles) and you also can try a few different spacers to minimize the width in the front. Since I liked the original factory SS wheels, I kept the ZR1 style wheels.

So after weeks of research, I found a workable solution to getting 315s on the front. After driving the twisties at high speed this weekend, I can't imagine why this is not a popular mod.

Did you notice the increased unsrung weight? My HD shocks seem to handle this in stride but my next mod may be Konis - at least in front.

z28bryan

iTrader: (7)

I noticed it slightly in the rear. First of all, the car's ability to hook a lot better with my 555r tires compared to other less grippy ones and then adding on the extra weight. I cringed a lot feeling like I was gonna destroy my rear end, but it can handle quite a bit.

robertbartsch

Yeh, I added a few pounds to the front with the C5 brakes and a few more with the 315 tires and 11 inch wheels.

I've only driven the car a few times now with the extra poundage upfront, but the mods don't seem to have any downside, at least so far.