getting more aggressive gears put into the s2k seems to make a humongous difference in acceleration, and they are a really popular mod for that car.

what's the reason that they are not as common in the Z?

 

It is common. Not everyone has the brains to do it. And install cost ads to the reasons

 

gears are byfar the best mod u can get on the car if its NA.. cost is like 1500ish installed, but most people like to do othe rmods w/ the install to save money...and it ends up costing like 2500 for just a gear swap
Plus, the gears are expensive as eff.

 

Actaully not^^ I think a company just recntly released a new one for like 600. So its really not that expensive anymore.

 

it is not the gears that are expensive, it is the labor, since if you are only buying or upgrading the gears; you would have to get people to take the whole **** apart and install it PROPERLY. That alone can cost you way more than that of the $600 worth of gears. That's why you hear people mostly do swaps..

 

Parts and labor generally cost around $1k now w/ the Central 20 gears.

 

what type of 1/4mile increases could one expect from swaping for new gears on a stock z?

 

You guys are confusing gear sets with final drives. A properly set-up final drive in a Z can drop .2-.3 down the 1/4....some will not see anything at the track due to worse 60ft's because of 1st gear being shorter with a 3.9 FD, others who can take avantage of the FD can see more. I havent seen any good 6MT data yet, but it will work.

 

im throwing the idea around but then i would be deep into 5th, that means one more shift...

but i have the traction so far, but that might lead to some axle-snappin fun!!!

 

Nice, central 20 gears are pretty cheap. Nissan has a set of 3.7's that fit the R200 diff also..its milder than 3.9's but almost as effective.