Team Camaro Tech banner

1 - 5 of 5 Posts

·
Registered
Joined
·
2,716 Posts
Discussion Starter #1
There's several here that have asked questions about fitting 275/40/17's on all four corners of my '68. There's now a new section on my website with pictures and text that shows the swap. Hopefully it explains most of the changes needed to make the fitment work.

If there's any questions please fire away.
 

·
Registered
Joined
·
2,716 Posts
Discussion Starter #3
Jody,

Geocities bandwidth limitations. One of these days I'll have to figure out how to write html and transfer everything over to my cable modem webspace.

Here's the text and pics from the website:
------------------------------------------------

With a stock subframe? Yes. With stock A-arms? No. In the following section the installation of Speedtech A-arms is covered, and they are the key to fitting big rubber on the front of the car. The arms allow for more clearance of the rim and have a built-in steering limiter that makes adjustments easy. Some steering needs to be dialed out and the suspension rebound travel must also be limited to around 2.5" from ride height. This is with -1.8* camber. With less negative camber the clearances will be better (upper arm is the limiting factor) and will allow for more steering and rebound travel. The car needs to be on a track to determine the best track-only camber setting, but for the street a -1/2 to -1* setting should work fine. Steering is fine around town with the limited turning radius if care is taken to allow for a bit more turning room than normal. The rears require rolling the fenderlip from the 10-2 o'clock position if you have the stock full-width fenderlip. The fenderlip on this car is very wide and can be rolled fairly easily. The difference in cornering power is like night and day. Braking is much improved as well. The ride with the RII autocross tire is harsher than the more ballon-like BFG Comp T/A ZR 245/50/16's that were on the car, but it's well worth the tradeoff. The 275/40/17 size is the same as the C4 'Vette so availabity and compound choices are very good Due to the increased backspace of this rim it was necessary to slightly re-clock the flexible brake lines at the caliper for rim clearance.

The overall width difference of a 255/50/16 on an 8" rim vs. a 275/40/17 on a 9.5" rim is only 1/4" (275 is wider). However, the 275/40 lays down nearly 1.5" of additional tread width to the road. That's huge.



 

·
Registered
Joined
·
2,443 Posts
I would say that tread width difference depends on the brand tire you get. Some of the 255/50/16 tires are very close to the 275/40/17. It comes down to the brand of tire, width of the rim and what you're willing to spend.
 

·
Premium Member
Joined
·
4,817 Posts
Carl, what's the tread width? Thanks much.
 
1 - 5 of 5 Posts
Top