GtoRx7

iTrader: (5)

Wondering if anyone knows the tranny ratios for a 1976 4-speed Rx-4 coupe. I have been searching for hours with no real luck. Thanks!

GtoRx7

iTrader: (5)

I guess I am not the only one! lol.

RX3SP

iTrader: (62)

Here you go:

1st 3.683
2nd 2.263
3rd 1.397
4th 1.000
5th 0.862

RX3SP

iTrader: (62)

By the way, there was no 4 speed tranny that came from the factory in a 76 RX-4. It was either 5 speed manual or 3 speed automatic. If it has a 4 speed in it, it's either not a 76 or the tranny is not original.

GtoRx7

iTrader: (5)

That is very interesting, I bought the car from a guy, original owner. The car has 54,000 miles on it as well. When I pulled the engine and transmission, everything looked entirely factory, as did the entire car. Where did you find no 4-speed was offered in 1976? Did they offer it in late 1975?

GtoRx7

iTrader: (5)

Ah, there is something else. The car is definitely a 1976, and pretty sure had a 4-speed, as the transmission mounts are much further forward on the chassis. The 5-speed tranny mounts further back, and I dont think somebody would go through all the hassle to make it look like a perfect factory job on the chassis. So, you have me wondering now!

Siraniko

iTrader: (13)

If the intake manifold has the reverse intake runners, then its a 76.

13BT_RX3

Reverse? Long primaries and short secondaries?

Siraniko

iTrader: (13)

The 76 runners are in reverse order of a typical manifold. The primary runners ran straight to the rear and front plates. Secondaries to the center plate.

Jeff20B

iTrader: (13)

This resulted in stronger primaries but weaker secondaries. Perfect for an RX-4 or Cosmo.

GtoRx7

iTrader: (5)

This car is without a doubt a 1976, it has the reverse primary/secondary runners, the improved fuel mileage stuff, the americanized front end revison and taillights, and the revised front suspension system using A-arms. Plus it says 1976 on the title.

RX3SP

iTrader: (62)

What's the build date on the car? Now that I'm digging through the cobwebs in my old feeble mind, it does seem like Mazda did use some 4 speeds in some of the early 76 RX-4's and RX-3's.
The gear ratios on the 4 speed are the same as gears 1 through 4 of the 5 speed.
Mazda didn't change the ratios until 1977 when they went to the closer ratio box.

Jeff20B

iTrader: (13)

5th is tall on those close ratio trannies.