Central 20 - 3.9 Final Drive
 

Ordered from Z-1 Performance and received the 3.9 drive last week. Had it installed and picked up my car yesterday. Feels great, just like stock but will rev much easier in every gear. On the freeway I could tell that my RPMS were a little higher ~10% than before, 6th gear is much more usable now. I'm sure gas mileage will go down a bit, but whatever it sucked to begin with so no big deal. I'd recommend this mod to anyone with a 6MT. The car certainly FEELS faster to me, which in the end is all I really care about.

The only question now is what I should do next, I've got the MREV2 + Spacer, the 3.9 gears, and z-tube intake. From what I've read on these forums it doesn't look like there is a whole lot I could do improve my car's performance without getting crazy or expensive. Will probably just do sway bars, intake (just for kicks) and call it a day.

Questions... how exactly do 3.9 gears make a 6mt faster? What gears are stock on our cars?

Thanks!

im nott 100% but i think they make the gears a bit "shorter" as people would say.. maybe lighter is a better word resulting in quicker revs

Stock ratio is 3.5 (3.3 if you're an automatic), so a 3.9 makes the gears about 10% shorter.

Did you buy the install kit 1 or the install kit 2?? when you bought these and are these necessary to buy?? the install kits that is.

install kit 1...don't think the 2nd kit is nescessary unless you have a lot of miles on your car.

So you opted for the $700-something package, that's just the internals (as opposed to the whole assembled unit)? How much labor (time or cost) was it for the install?

Paid 528.50 shipped from z1 performance inc. Install was $550 - could have had technosquare do it for $100 less but they're all the way up in LA and I was eager to have it done. Either way I'm happy with the result.

Thank you. Getting close to a month now. Still loving it just as much?

Absolutely - car is a blast to drive.

I'm really considering this again. My hesitation is that I might trade in a year or two and I could just add the money to a downpayment fund...

...or spend it, forget about it and enjoy it, and then think about trading or not later down the line. I'm leaning toward the second option. :p

Before you trade the car in, you could probably find someone who would be willing to swap their stock 6MT rear pumpkin with you for $$ plus pay for the install - so you could get back some of your money.

True. Either way, this mod is looking better and better. That is, after I get the clutch install sorted and completed.

Well, in reality, it doesnt really make a car faster. What it does is just make your gears shorter, so in fact, you do have a quicker acceleration in the lower gears.

It works just like it works on a bike; the shorter the gears, the faster you can pedal and get up to speed. The longer the gears, the longer it will take you to get up to speed, but will have a better top speed.

(Anyone correct me if im wrong).

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^^ Thanks, that makes sense