ABS and tire size questions... help me please

[Killercanary]

Hello all, I'm back from Vegas and on a mission to get my car done since the race season starts very soon. I'm waiting on my wheels to arrive (bogart RR10's in 17X9/17X10.5) and need to get my tires ordered. I have concerns regarding the ABS. I need to know how much or a difference in diameter between the front and rear tires I can have without adverse effects on the ABS. I am definitely running 315-35-17 nitto DR's, but my concerns are for the front. Discount tire keeps trying to sell me 275's, but I don't a tire that big up front. Ideally a 265/40/17 is what I need, but its not available from nitto. So I'm forced to run either a 255-40-17 or a 255-45-17. The 255-40-17 is the one I'd rather have as it has less of a sidewall and will look better, but it's overall diameter is 25.08" and the 255-45-17 is 25.95" The 315-35-17 is 25.79" Anyone running either of these setups or have any input?

On a side note when I run at the track I run 26X10.5X16 ET streets out back and 245-50-16 tires up front and I have never had an ABS light or anything come on, and I'm sure the ET streets grow some on the top end making the difference even greater between the front and rear... maybe I'd be OK.

 

[Joes95GT]

Paul, there are plenty of guys running a 17x9/17x10.5 tire combinations that have no problems with the ABS. I'd get the 40 series side wall, just for the aesthetic reasons.

I can't see how the 0.71" will make any difference as far as the ABS is concerned. Look at all the guys running skinnies on the front with regular street tires. I'm sure if there were adverse affects from doing so, there would be less people doing it.

Good luck going for the 11's. I can get moving when Edelbrock ships me my heads, then things could get ugly .

Joe

 

[swingline]

Are you dead-set on getting Nitto's for the front? Why not just get a cheaper tire for the front in the size you want? Like Joe said plenty of guys are running 17x9 and 17x10.5 without any problems.

 

[Killercanary]

Joe- I'm hoping those guys will chime in here and let me know what tire combos they are running. As for the 11's... I don't know what has changed in me, but my quest and desire for more power is slowly going away... I almost don't care anymore. I just want to make my car look a little better and continue to tweak what I have. BUT at the same time i will be at the spring SSOTN nats to try to dip even lower into the 12's. I highly doubt I'll see 11's in the shape my car is in now, but I know there is a 12.20 or better in the car with the changes I have in store... time will tell!!! I can't wait to see how your combo makes out. If I can help you out in any way, let me know! Will you be at the SSOTN race?

Mark, I'm dead set on getting nittos all the way around. I've run mismatched tires for too long, I want a matching set, or as close as I can get to one as possible.

 

[rel3rd]

Paul, Keep in mind that the Nittos are naturally "smaller" in width than most other brands. I use 275/40 Hankook Ventus HR2's on the front of mine, FWIW, and they are pretty big tire but I like the looks and handling alot. I have brand new 315/35 Nitto drag radials for the rear, but have decided to save the BFG's another few weeks just for you...

 

[Joes95GT]

I highly doubt I'll see 11's in the shape my car is in now, but I know there is a 12.20 or better in the car with the changes I have in store... time will tell!!! I can't wait to see how your combo makes out. If I can help you out in any way, let me know! Will you be at the SSOTN race?

Wait until race season, that desire will be back. Let's bench race a little bit - you have about a tenth left on the table just in your launch. We'll say that knocks you down to a 12.21. You've taken how much weight out of the car? There is the 12-teens right there. With the right conditions, 12-oh's are there. IMO, they are closer than you think.

I'll be PM'ing you in a few weeks about a few minor things. As you can tell, I called Ed about the cam. The combo should be pretty stout.

Unfortunately, I will not be at the spring SSOTN. I'll be away for almost two weeks and I will be coming back the day of SSOTN. I may be up to watch, but the car won't be in any condition to pound on. I'm planning my schedule around the fall SSOTN. I'm going to do everything in my power to be there.

Anyhow, back to the post, I talked to my old man about it and he said he's never heard of any such problems (with the wheel/tire diameter and ABS). Granted, just because he's never heard of anything, does not mean that it is nonexistant. He said that if differences in tire sizes would cause problems with the ABS, Ford would void warrantees on cars with aftermarket wheel/tire sizes other than the suggested size, and since they don't do that, everything should be fine.

Joe

 

[Killercanary]

Joe, I hate to bench race, but I'm normally good at it. I'm dropping roughly 60lbs off the front of the car with the 16lb weight loss in the PBR brakes, and roughly 40lbs with the bogart skinnies I'll be running. I'm also hoping to have the battery in the trunk at that point. I plan to run less air in the tires next time out, I had roughly 16-17lbs of air in them on the 12.31 run and they spun. My car squats too much on the launch and unloads the tires quickly, I hope I can bandaid tht with less air in the tires yo help cushion the power hit. I plan to run it without the pass seat again, but other than these things I don't know what else to lose in terms of weight.

 

[Slow5.0]

Paul , a few weeks ago I did burnout with my old tires and guy who installed my old rear tires on front mess up with one tire so he give me 2 use tires for front BUT those two tires are 235/35/17(23.5") , my rear tires are 275/40/17 nitto DRs and that same overall diameter like 245/45/17(25.7'')
So now at 48+ mph ABS light come on
I think if you have 2"+ difference ABS light come on But your difference is .7 so you don't have any problems

 

[Killercanary]

Thanks for the heads up!!! Your the first person to give me a definite answer as I don't think anyone else has experienced this. Thanks alot!