Hi,

I drag race my 07 6mt Z quite a bit, and was thinking about getting 3.90 gears to improve my times. If I'm not mistaken I have 3.54 gears stock. My first 350z was an 05 6spd base, and I raced that quite a bit as well. In that car I had to shift to 4th gear well before the end of the 1/4 mile.. but in my 07 I am at about 7400 rpms in 3rd gear as I go through the traps. It's pretty much a perfect drag gear for the engine.

My concern is this-- Since I know that I'm going to want to do some N/A mods on this car eventually, are gears a good place to start? If I add let's say.. 30 or 40hp to the car, are my RPMs going to climb faster than stock so that it will force me to shift to 4th gear before the traps? If I get 3.90 gears, I will of course have to shift to 4th before the traps.. so I'm concerned that this will hurt my times rather than help them. Sorry to throw so many questions out there at once, just figured it would be better to get them all out of the way.

Biggest question/top priority-- Does anybody here have experience dragging a 350z with 3.90 gears on a 1/4 mile track? How did your times compare to running with the stock gear? Thanks.

 

i say if your worried about messing up the drags/shift times then dont get gears, just get basic bolt ons. Although if you did get the 3.9gears then i would venture to say you would be able to use a little of 4th gear before you go over the line. Sense you will be loosing a couple hundred rpms. i hope this helps with your ?'s

 

Thanks for the reply. I know that if I get 3.90's, I will definitely have to use 4th gear before the stripe, since I'm at the very top of 3rd gear with the 3.54's. I was hoping that someone who ran their HR down the 1/4 mile stock, and then with 3.90's could tell me if it's worth it. I'm wondering if that 1 extra shift will negate most of the gains from the improved acceleration gear.

BTW- do you ever take your Z to San Antonio Raceway?

 

O, wow i never realized you were in austin lol. Ya, i have a couple of times and to me i honestly dont like the drag strip. Maybe it the days i go or something but i can never hook up at the start. Also, when you shift you do loose a little time because you cant keep the power going. I usually shift into 4th by the time i get to the end, but i try to do it as fast as i can .

 

What RPM do you usually shift at? I've taken my Z's to 4 different drag strips.. so far I think San Antonio Raceway is my LEAST favorite in terms of traction. You would think it would be better than alot of the smaller tracks due to the budget for track maintenance, bigger events there, etc.. but I haven't found that to help my times. I'm almost always slower there than at other tracks. Plus the track officials there are a-holes about going through the water if you're not running drag radials or slicks. Just generally a less pleasant experience for someone just trying to have a little fun with their street car.

 

I'd run 4.08's if you have an HR....

 

You can finish 1/4 mile in third gear? I find this guestionable, but if you say you can do it than OK. Anyway lets see some of your best time slips.

 

Well san antonio race way the one drag strip i been to. I usually toping out of 3rd, some times i just bounce the rev. limiter for a mili-sec. Ya, i agree with you about s.a race way, they use to let me go in the water when i first started going there now they dont 0_o. either way water wont help to much sense we have street tires, but i did get my best time there at a 13.8 with going threw water and a small rolling burn, also i have to launch low around 2k. If i go any higher i get major while hop and i have that csc issue, so i cant do anything to hard unless i want my clutch to stick to the ground 0_0.