A6 Coyote, inconsistent track prep...ET Street Bias or Radials?

[KrisR]

The track that I typically go to is a little 'marginal' with their track prep (if they do any at all)...last time I went there with my current setup (Boss mani, CAI, O/R X, tune, Circle D 5C, stock 3.15s) I was only able to manage 1.67-1.68 60-foots on 255/50-16 ET Street radials. Another track I went to (farther away) later in the season I was able to get a best 1.59 60-foot with the same tires and setup.

I got a set of Racestars from Beefcake (15x8 and 17x7). I already have the front tires (215/55-17s) but I'm shopping for the rears.

I know that most cars can run quicker on radials if they can hook, and that most people use radials on automatic cars. I also believe that bias-plies can be more consistent on marginal tracks, and are lighter, but drive like shit on the street if I need to drive on them.

I'm trying to decide between 275/50-15 radials or 26x10.50 (or 11.50) bias plies...assuming I keep the 3.15 gears. I could also throw in a set of 3.31s and go with 275/60-15 radials or 28" bias plies, but that obviously will be more expensive.

Thoughts?

 

[beefcake]

The track that I typically go to is a little 'marginal' with their track prep (if they do any at all)...last time I went there with my current setup (Boss mani, CAI, O/R X, tune, Circle D 5C, stock 3.15s) I was only able to manage 1.67-1.68 60-foots on 255/50-16 ET Street radials. Another track I went to (farther away) later in the season I was able to get a best 1.59 60-foot with the same tires and setup.

I got a set of Racestars from Beefcake (15x8 and 17x7). I already have the front tires (215/55-17s) but I'm shopping for the rears.

I know that most cars can run quicker on radials if they can hook, and that most people use radials on automatic cars. I also believe that bias-plies can be more consistent on marginal tracks, and are lighter, but drive like shit on the street if I need to drive on them.

I'm trying to decide between 275/50-15 radials or 26x10.50 (or 11.50) bias plies...assuming I keep the 3.15 gears. I could also throw in a set of 3.31s and go with 275/60-15 radials or 28" bias plies, but that obviously will be more expensive.

Thoughts?

for hooking, the 275/60/15 tire is hands down the best tire you can get as far as a DR. the radial pro is ridiculous, it's what I'd recommend

 

[Jenkins]

for hooking, the 275/60/15 tire is hands down the best tire you can get as far as a dr. The radial pro is ridiculous, it's what i'd recommend

x2

 

[Benchracer]

Go with the 275/60/15 PRO radial. You wont regret it.

 

[spdracr0]

I have been 1.246 in my fox. 302 based/C4/4.56 on motor at a track that I though was marginal at best. Coming off the brake at 6600, so it shocks the tires a lil...they work

 

[spdracr0]

dang sorry, on the pro radials

 

[KrisR]

Thanks all. I was hoping to avoid switching the gears for simplicity's sake but if the 28" DR really works that much better than the 26", I guess I will consider it.

As it is right now I am going through the traps at 7400-7500 in 3rd which is perfect. The 28" would drop that down to around 7000. 3.31s would get me back to where I want to be with the 28s.

 

[JohnRichard]

Gear Ratio Speed Calculator

Optional 6-speed automatic

1st: 4.17
2nd: 2.34
3rd: 1.52
4th: 1.14
5th: 0.87
6th: 0.69

 

[KrisR]

Gear Ratio Speed Calculator

Optional 6-speed automatic

1st: 4.17
2nd: 2.34
3rd: 1.52
4th: 1.14
5th: 0.87
6th: 0.69

Yeah, I use another one at www.f-body.org/gears all the time. Thanks though.

 

[1Bad5.0]

I have 3.15 gears and run the 275/60/15 DR ....I have very similar mods as you and go through the lights at 7250 rpm.....also get consistent 1.56/1.57 sixty foots...I have a 4C

 

[KrisR]

Well I guess I said 'F' it. I found a nice low mile takeout 3.31s for $60 and I will probably get them put in this spring. Car has 45k miles and should probably have the diff checked out/fluid changed anyway.

Going with 275/60s most likely.