Would this be possible, would the shift point be messed up? Is it hard to swap?

 

Won't be that much of a difference, rpms wil go up just a tad.

 

If you are going to swap might as well go to the 4:30 or 4:33

 

Hell if you're willing to sacrifice top end for some good acceleration, go with the 4.777. With the tall auto ratios, that would be a nice combo.

 

I second that...Dont bother just going to a 4.1 get a 4.33

From what I've heard from other people who have done it, it will require about 5-7 hours of labor (around $400)

Sure its a steep price ($800 including install) but I think its one of the better if not first mods that should be done to an auto. That gives a ~10% performance gain across all RPM ranges, without requiring any additional mods (ie ECU upgrade)

Thats a big advantage, as most of us auto owners know we have a disadvantage Vs. the 5spd when it comes to modding. Namely the lack of aftermarket ECU support that integrates with our cars well. Yes there ARE several solutions out there but none that I would call ideal.

I think a lot of us are stuck at the same point I'm at. DP, CatBack, PowerPulleys and other reliability mods. With no clear upgrade path.

Even so, I've read countless posts where auto owners mod the **** out of their cars and still only manage stock 5spd times. How can that be? Because the ignore the only thing that seperates our cars.

The stock FD auto tranny and driveline. This by far the weakest part of the performance equation and should be the first thing fixed. 4.33 gears and an upgraded Torque Converter, whatever.. Anything you can find to help.

This can only benefit all your future mods.


Look at the other 5spd/AT sports cars that share our delima and you wont find the same HUGE performance gap.

Supra TT
Corvette C5/C6
300zx

I dont have the numbers off hand but I doubt any of them are more than .5 secs difference in 0-60 times and lower in the 1/4 mile.

 

I forgot here's a link that shows rpm's & speeds for the different R&P ratios


http://www.rx7.com/cgi-local/3catalog.cgi?cat=2&part=6

 

i wish those could be done in auto gear ratios, thanks for the link

 

i have an automatic as a daily driver....hehe
my other is a 5speed so no flamers

i have the 4.3 in my car. you have to buy some shims to make it fit perfectly. its a real pain in the *** but worth it. sadly, the car still shifts into fourth gear at 120mph lol
you still get good gas milage. at 80mph my rpms are still around 3300.

 

I just swapped my 3.91 to a 4.30 and could feel the difference right away. Should have performed this mod years ago. Cost for gears and installation should be close to $1,000. Suggest a transmission shop do the work, for special alignment / shims will be required. Note that your odometer will be off by about 12% and your speedometer by 5% (with 16" wheels). These will require adjustment by a speedometer shop or with aftermarket devices. The best way to describe the difference in driving with the 4.30, is when in Drive the car feels like its between 3rd and Drive, as for rev's will increase by up to 750 rpm versus the 3.91.

 

is that +/- 12% on the odo?

 

Its +12%. Check your current rear against 10 mile markers on a highway (do not use 1 marker). After the new 4.30 is installed, repeat the process. My odometer read 11.2 miles.

 

If you go, go to 4.3. It should improve your 1/4 mile time .1-.2 seconds depending on your RWHP.

Ken

 

Every1 beware of this ******* MrBrain...he tried to scam me on PAYPAL and then not send out the product i gave him $ for...DO NOT purchase anything from him!