[hotrod182]

I was pretty pleased that I was getting 2.0X secs on my 60Ft times with the stock runflats. I know most people think there are great gains to be made by switching to non runflat tires. I was curious too, so I took the 19" (245/35/19 front & 275/30/19 rears) from my 06 M3 and put them on my stock 335i steptronic sedan. The first 3 runs on the graph are on the 19" non runflats. (Exclaim UHPs). The very last run (Blue line), was a run on the stock run flats in February. It was much colder in Feb, probably 50F. This morning the temp was 70F, but very humid. As you can see, they are all within 100ths of a second. You can see how consistant the runs are. Launching/driving with consistancy is the same thing that has helped me at the track. The runs this A.M. were with the dtc/dsc off. The one on the run-flats was just with the dtc off. I don't really think it really made that much of a difference in my situation.
Interestingly enough, compared to the 100F 2700Ft LACR, you can see the car runs about 4mph faster under these cooler temps, at sea level. So this equates to about a 40hp average loss when I was at LACR. You can also see the consistancy of the GTech Pro RR. If you remember, last week when I ran it at the strip, it was amazingly accurate.
I was surprised the tires/wheels seemed to fit as good as they do. The front doesn't rub at all. But on some slower dips, turning in/out of driveways, I am getting some rubbing noises I believe from the right rear mainly. I want to figure out what is causing this noise. I can go over faster bumps, speed bumps, swerve left/right, and corner hard, and it doesn't rub. Just when turning into driveways, etc. Has anyone else had this problem? I know some people were running 265's instead of 275's in the rear, so maybe this is a common problem? Other than that, I love the way the car handles. It is less skittish at high speeds. (More planted). And the thing absolutely sticks like glue when flying through on/off-ramps. It almost seems like it corners better than the M3 with these tires on. And with these tires/wheels, it now has the high speed stablity closer to the M3 also.
A bit of a disclaimer though: The runflats have about 4000 miles on them, the 19's are 95% worn out (past the wear bar indicators). In fact, I just ordered new rear tires yesterday.

[ljg335i]

I hit 1.98 best on stock 18" RFT and have several 2.01-2.03 times

[hotrod182]

Originally Posted by ljg335i

I hit 1.98 best on stock 18" RFT and have several 2.01-2.03 times

Was that with the Turbo Tuner? Your best time, 13.53 @ 102mph was with the TT as well?

[ljg335i]

No no, all stock - no TT yet

[bnj]

Man, I really like the way you speak
Thank you for the information.

[musc]

If you launched at the same RPM, then you wouldn't expect any improvement. With the non runflats, you should be able to torque brake it higher and improve the 60ft some, that is, when you get new Generals.

Good info as always

[hotrod182]

Originally Posted by catm3

If you launched at the same RPM, then you wouldn't expect any improvement. With the non runflats, you should be able to torque brake it higher and improve the 60ft some, that is, when you get new Generals.

Good info as always

I tried one run with higher rpm, it just spun, and I think my time was a 13.7 or so at 104.7mph. I made 5 runs total. The 3 above, and the 2 below with excessive wheel spin. I too thought, "what if I launch with higher rpms?" and the resultant 2 runs below show what happens when you get too much wheel spin on take off.

[ljg335i]

Originally Posted by hotrod182

I tried one run with higher rpm, it just spun, and I think my time was a 13.7 or so at 104.7mph. I made 5 runs total. The 3 above, and the 2 below with excessive wheel spin. I too thought, "what if I launch with higher rpms?" and the resultant 2 runs below show what happens when you get too much wheel spin on take off.

Are you running any engine mods?

[hotrod182]

Originally Posted by ljg335i

Are you running any engine mods?

Nope, totally stock car, except for the 19" tires and wheels today. Didn't seem to help, or hurt the 1/4 mile times. But the thing corners amazingly.

[Cadillac Johnson]

Going from 18's with super stiff sidewalls to 19's with very small, pretty stiff sidewalls isn't going to do much, if anything. Probly a little lighter, but that's not gonna do much for traction. There really wont be much change in 60' times.

You'd be better off sticking with the 18's and putting some cheap winter tires on there.
winter tires = budget drag radials

[ljg335i]

Originally Posted by Cadillac Johnson

You'd be better off sticking with the 18's and putting some cheap winter tires on there.
winter tires = budget drag radials

thats the first ive heard of that method

[Cadillac Johnson]

Think about it, drag tires have big, soft sidewalls, soft, sticky compound.

Winter tires, have soft sidewalls, size depends on wheels, bigger the better, they are very soft so they stay soft in freezing weather, and they're made to grip as good as possible. Being siped doesn't hurt either when your only going in a straight line.

They really do work very well as a budget drag radial.