tire size and quarter mile logic

[TEAMJACOB]

If my car stops making power at 6k but I'm trapping in 4th gear at 6300-6400 at 115 mph, then can I assume a faster et and higher mph if I switched from a 26in tall tire to a 28in tall tire? Car runs 12.1 currently and has 4:10s. Seems like it would be in the powerband longer if I had the taller tire. Tia

[Doug Hatton]

You could expect about 430rpm less when crossing the line at 115....

[TEAMJACOB]

So only engine speed is affected? Mph and et stay the same?

[Trick Pony]

It could also effect your 60-ft slightly. If you have traction problems it may solve them because of the taller tire; if you don't have traction problems then it may slow your 60-ft a hair due to the taller overall gearing.

[Doug Hatton]

Hell, I don't have a crystal ball... If it stops making power at 6000, I'd assume it'd pick up just a little ...

[holeshot]

Your running through your torque band.
Yes going to a 28" tall tire will hook better and you WILL pick up speed and E/T.
A pair of 28" X 9" slick on an 8" wheel is perfect for your set up.

[TEAMJACOB]

Yeah wheel spin has been an issue with a best of 1.72 and it should be lower. I thought it would help plus the 26 in looks too small on a 2v. Hopefully it can give me an 11.xx time slip finally

[Johnc]

Yeah wheel spin has been an issue with a best of 1.72 and it should be lower. I thought it would help plus the 26 in looks too small on a 2v. Hopefully it can give me an 11.xx time slip finally

spray?

[Moose Jr.]

28" tires are not always the answer. The right 26x10 will work fine. I'm assuming this is a stick car. What suspension mods do you have? What brand and type slick are you running? What size wheel? Do you know what your pinion angle is?

[TEAMJACOB]

spray?

Boost

[TEAMJACOB]

28" tires are not always the answer. The right 26x10 will work fine. I'm assuming this is a stick car. What suspension mods do you have? What brand and type slick are you running? What size wheel? Do you know what your pinion angle is?

Suspension mods are lacking. Upper and lower control arms is about it as far as suspension goes. It is a stick car and am running 26x10.5 mt et streets (not the drag radials). On an 8 in wheel. I agree with were u are going as far as suspension being the culprit on the 60 ft and that was brought up by someone else. The real reason for the 28in tire inquirey is trapping way over my redline and powerband at 6400 rpm with an unbuilt motor under being curious as to picking up any by staying in the powerband. I could always change gears but 4:10s are a lot of fun

[holeshot]

28"X 9"been there done that !!!!!

[TEAMJACOB]

28"X 9"been there done that !!!!!

Did u mean this as advice? U had similar issues?

[holeshot]

You asked and I just wanted to give you the best advice from experience !

[Doug Hatton]

I would think that a general rule of thumb would be to gear your car so that you're at the top of your 1:1 gear at the end of the 1/4. It shouldn't be rocket science. After that, you can focus on traction/suspension issues. I run a 3.27 gear and a 26" tall tire...why? Because I cross the line at about 5600 in Drive...