the_glass_man

iTrader: (2)

Where is the best place to get 4.77 gears???
I know RX7.com has them, does anyone else have them???
Jason can you get them for me???

GoRacer

iTrader: (2)

That's weird, I thought both Petttit and M2Performance both carried them?

RE Amemiya from jt-imports
http://www.jt-imports.com/U.S.Atop.htm

RecKleSs

It's a pain in the *** to get the ring & pinion from a shop. It took me a really long time and I ended up purchasing it off Shane Racing.

Also, the 4.77 is a little overkill, however, you might like it. I've done a lot of research and the 4.33 turned out to be the best for my needs.

Try Ari's shop at www.RX7.com They carry a lot of parts and they are awesome.

Good luck, because you are really going to need it.

black99

Ari I think has/had 4.33's(??) in his car so that should tell you if you really need 4.77's. In fact I haven't ever seen anyone running 4.77's in a FD. Also the RE Amemiya or nice but I think they are in the upper $700.00 range shipped. RE is the king but you might be able to find them cheaper over here.

the_glass_man

iTrader: (2)

The only guy to ever do 10's on a stock engine and stock turbo car had 4.77's.
I've heard that if you are going to bother doing the swap at all, it makes almost no difference if you go to 4.3 gears.
Notice that the fastest stock turbo cars in the county have upgraded gears of some sort.
Besides I have 275/40/17's which will dampen the effect.
I think the reason you don't find many cars with them, is because 1) they are harder to get and 2) they cost more.

black99

Well you know more than me. I've never seen any written info on the effect of 4.77's on an other wise lightly modded FD but it seems like you've researched them.

For all our sake I hope you do get the 4.77's test them out and see what kind of numbers you can pull at the track. At least then they'll be some track tested idea of what they can do for us.

black99

BTW you were speaking of Kevin Wyum?

black99

Sorry to post ***** but to correct myself. Canman's price for a 4.77 RE Amemiya gearset isn't bad at all: $520.00

the_glass_man

iTrader: (2)

I've done some researching, nothing really deep. Messing with gearing and ratios isn't for the faint of heart.
There are some performance numbers, Both Ken and JimLab have been kind enough to provide cartest information in a few other threads.
While not track tested, the info seems to prove that the gearing would provide for better acceleration at the cost of a redline limited topspeed (which it is if you have enough power anyways) but how often do you plan on going 204 mph??? And of course more fuel consumption while driving on the highway.
So if it offers better accelertion why wouldn't you want to do it???
Yes.

Thanks for the tip, that is a good price, much better then most I have seen.

I will look for performance data later and post it.

the_glass_man

iTrader: (2)

Here is some data that jimlab posted in another thead.


So back to the question... gear limited top speed in the RX-7 is as follows (P275/40-17 tire)...

4.10 - 207.2 mph
4.33 - 196.2
4.50 - 188.8
4.77 - 178.1

In a ~360 RWHP RX-7, 60-150 (highway acceleration) is as follows...

4.10 - 16.21 sec.
4.33 - 15.99
4.50 - 15.77
4.77 - 15.48