I'm about to order a 9 inch and was curious what gears you high power blower guys are runnin? Car is an M6 with a 26" tall tire aiming for around 700rwhp.
Looking at 3.70's or 3.89's

 

I like my 3.50's in my 9". It takes some practice to launch it with a street twin. 1st gear doesn't last long with 3.50's in a high hp m6 and it will be even shorter with lower gears.

 

funkybird, what transmission?

 

I would say 3.42. A FI car with that much power will need something along those lines. Unless its an all out race car. Is it? What are your plans for the car?

 

The trans is now an M6 with a Mcleod street twin, just did the swap this winter. Car is mostly for street use but sees the track a handful of times a season.
Thanks for the responses guys, it helps alot!

 

I would go something like 3.23,3.42,3.55. I think you be seeing 5th gear in the 1/4 if you go with a 3.73 or 3.89, but its up to you. good luck

 

If you don't mind me asking, what times you run, power you make and what rpms your runnin at the end of the track?
our setups sound pretty similar.

 

My car is approximately 525 HP since I pullied down to 10 psi(4.5" pulley). I don't have any track times with my 9" yet because our track was flooded this year. Mine is mainly a daily driver. Sorry I cant help out more. I've been doing alot of upgrades to the suspension trying to find traction. I will try to make a run this summer some time. 3.50 or 3.23 would be my recommendation with a M6 tranny because of the close ratio of the gears.

You can fly out here and drive it if you want...Its a beast when I go WOT but drives like a BMW around town. LOL

 

Wow, thats a very nice offer! Haha I have a 4.25 pulley on mine and it's gettin me about 12-13psi and feels like an animal! I almost have the suspension done on mine. Full BMR but I still need a torque arm and a body mount and I would like to get the extreme rear sway bar too. Isn't that list never ending? LOL

 

Ya. The F1A makes alot more power at the same psi as my old P1SC. I thought I had pretty good traction until I put the new blower on. Let me know how your suspension works. Best thing I've done so far is the spohn relocation brackets. When you order your 9" ask them if they can weld on their relocation brackets so you don't have to buy them later. Do you do your own OBD2 tuning?

 

I have lt1edit and a tune from pcmforless just to get it in the ball park. I know a few local guys who have done alot of tuning and i'm slowly gettin into it, i'm pretty hesitant to change things with it haha!

 

I have a 3.89 and have a lot less hp than you do and my first gear is worthless even with 315 Nittos. I agree with the above posts that you should look at a 3.50 or higher gear. I think the next time I am ready to spend some $$ on my car, I'm going to try a 3.50 gear. Like you, I drive mine mainly on the street and just go a few times to the track on test and tune night to play.

 

3.42's in mine and I wouldn't change them.

Rich

 

I'm glad I threw this out here, thanks guys!

 

I'm with the others that reccomended around 3.42's. With 700 to the wheels, anything in a higher gear ratio will not do anything but give you less traction and force you to not be able to finish the 1/4 in 4th.

If its gonna be over 700 RWHP, I might even reccomend a 2.73.