jr

Just curious as to how you like them vs. the stock 4.1's. I'm doing a 5 speed swap over the winter and was contemplating then vs. the 4.1's. Is it a noticeable improvement in accelartion? Anyone have 1/4 mile times stock vs 4.3's? TIA.

jackc

I have been using 4:3 for a couple years now. I should give you
2 tenths of a second in the 1/4 mile.

Better acceleration. You won't regret the 4.3 gears. I had a lightweight flywheel that I think was a little too much in combination with the gears. It made first gear kinda useless.
I still have the factory squencials so I put the factory flywheel in.

But if you have non-squential then the light weightflywheel should really help. regards jc

Astro

hey jackster
aleem here
so you're saying the 4.33's and a lighter flywheel would be a decent combo for some non-seq;s?

Freaky Monkey007

I thought when u increasesed ur gearing u made it harder 2 accelerate and easier 2 get a top end?? Do i just have this backwards? I always seem 2 forget this.

jackc

Hi Aleem"Astro"...

Yes a lightweight flywheel and non-squential would be excellent.
If both turbos are coming on line at the same time. You will have more lag. ..
But if you have less rotational mass to pull you can spool up faster with a lightweight flywheel.

Cheers... jc.

Now that I am steet ported I might get a slightly lighter one...
Maybe a 17 pd-er.

WhtRocket

I have been wondering about this. I don't really need the 180mph top end but a quicker 0-60 time or 1/4 mile would be nice. Only .2sec off the quarter mile time? really? Is it worth $450 + install?

JoeD

most people say they dont really notice a difference with the 4.30 or 4.33 gears. just go all out and get 4.777 from RP. it limits your top speed to about 155....but thats fast enough.

arie1955

Due to my insistence that my read end is making a clunking noise when I shift, i decided to buy the 4.30 rear to replace it. I think it was well worth the 500 dollar part bill ,ad 280 labor bill. The car feels so much faster. I can burn my kumho's all the way into the beginning on 2nd gear. My car is bone stock, and thats the only thing i did to it. Plus, i also have a secondary boost problem (10-8-5), and the car still feels so much faster. I plan to actually get the boost problem fixed (been tied up for 3 Months). Once I get it fixed, will repost the results. But once again, if your itching to spend 800 bucks, the gears are well worth it.

JoeD

how is the highway cruising with closer ratio gears?? like cruising at 65 in fifth...is the increase in RPMs and noise bearable if you are just tired and want to go home??

machinehead

I would think it would help a lot in the 1/4mi. Especially if you are running slicks which will offset the gearing some due to thier size. With MT ET streets in like a 26X10.5X16 I am just maxing out 3rd gear in the 1/4.
I am really thinking about doing these myself but i would like to think I would get more than .2 sec out of it.

FD Seeker

With 4.3, can you still hit 60 in 2ng gear?
If not, another shift will certainly hurt your time.

We need one of you math wizards to chart out the max speed in each gear using 4.3s.

rynberg

Here's the link to rotary performance website, they give the rpm's for different rear ends:

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

kwikrx7

I've heard with 4.77s that it is VERY noticeable in acceleration but will hurt top end and gas mileage. I'm sure they are worth atleast .5 sec off 1/4. I'm sure they scream on the highway and would get annoying after awhile especially if you just want to go home like JoeD said. Not sure if 4.3 or 4.33 would be worth it. Dunno

cymrex

iTrader: (2)

Did anyone else notice that with 4.30 you can still get to 62 mph (100 kph = 62.1 mph) in 2nd gear. That is why they were willing to upgrade the latest RX-7 in Japan, the can still get to 100 kph without a second shift.

GoRacer

iTrader: (2)

Haven't done my tranny yet cause i'm doing my JIC suspension and bushings. I was looking at the 4.33 from M2 or Pettit (probably the same) but what I was worried about is how high and loud the RPM's would be in 5th gear cruisin the freeway at 70mph. Especially if I change to a higher (Pettit)5th gear as well.

I think I read it's only 300rpm higher in each gear but I don't know how much higher in 5th if I also replaced 5th gear to.

JoeD

among all of the other questions...what can you do about the speedometer?? im pretty sure it will be off a significant amount after you mess with the gears.

i would also like to know, as aksed above, how is the highway cruising??

SPIN HRD

I heard if you run about a 285/40/17 it pretty much equals out with the speedo. I will have to find out when my car is running again. I know a cop that can clock me. Also if you are going to drag race dont get too light of a flywheel it will give a you a shitty jump off the line.

GoRacer

iTrader: (2)

I am at 3k RPM @ 80-MPH:

Can you guys that have the 4.30 and/or 4.33 check what the RPM's are @ 80mph in 5th gear...or 65/70, so we can compare them please.

thanks

BTW: It is $300 to recalibrate the speedometer.

justin

5 mph higher difference with the 4.33 gear on the speedo
I was hoping I could get into 4th gear sooner in the 1/4 but last year didn't notice a better et but did pull
1 mph faster.
BTW these gears are fine for the street no problem.....

jspecracer7

...backwards. 4.33 gears will get you lower top end and slightly better acceleration vs. the 4.10 gears. The 4.77's would be great quartermile time...but they'd suck driving around town since you'll be changing gears all the time.

RTS3GEN

Great option the 4.3's but good luck finding a set. Been looking for about a month and no one has them in stock. Just 4.77's at RP and I do a lot of hiway driving, 4400rpm in fifth at 77mph doesn't sound like fun to me, no thanks.
Art

spyfish007

If you change tire size to make your speedo right then what gain is there?

rynberg

Spyfish007, thanks for pointing that out, I thought something was funny about the earlier post, but I couldn't put my finger on it. Yeah, running a 4.3 and larger tires means you just spent a lot of money and accomplished nothing!

jspecracer7

...not exactly. You changed the tire size to correct your speedometer, however your car will still accelerate faster and you'll lose top end.

...we've proved it over here by changing the 4.30 out of Dragon's car to a 3.90. VERY tall gearing swap. Had it calibrated, and now the top of 2nd Gear is in the 120 kilometer/hour range vs. 80 kilometer/hour range.

...so do you see the difference?

JoeD

why did he change it?? i dont really see the point in loosing acceleration to gain some top speed.