What gears would you choose?

[zerow]

This goes with Datzenmike's sticky about 4 speed automatic transmissions from Nissan Maximas for use with older Datsuns.

I now have the 4 speed automatic transmission, but I have questions about which set of differential gears I should use. I have an R-160 with 3.70:1 gears and I have an R-180 with 3.36:1 gears. I got the 3.36 gears because I wanted a little screamer with 5 speed, but now that I am home from the Army with permanent nerve damage in my legs, I just cannot drive stick anymore. I live in California where I would be likely to be on the freeway more, but I don't want to have a slug when I drive on the streets, either. I will be running a L20B with SUs under the hood, for originality.

 

So what would you guys do...? :confused:

[bonvo]

This goes with Datzenmike's sticky about 4 speed automatic transmissions from Nissan Maximas for use with older Datsuns.

I now have the 4 speed automatic transmission, but I have questions about which set of differential gears I should use. I have an R-160 with 3.70:1 gears and I have an R-180 with 3.36:1 gears. I got the 3.36 gears because I wanted a little screamer with 5 speed, but now that I am home from the Army with permanent nerve damage in my legs, I just cannot drive stick anymore. I live in California where I would be likely to be on the freeway more, but I don't want to have a slug when I drive on the streets, either. I will be running a L20B with SUs under the hood, for originality.

 

So what would you guys do...? :confused:

 

 

i personally would go with the 3.70im running 3.90 out the back of mine and it goes ok lol and there slightly higher gearing so it will take off slower then mine but have a higher top speed

[datzenmike]

A 3.36 is quite low giving poor take offs and slow acceleration. The o/d 4th gear is just under 0.70 (more than the close ratio 5spd 280zx tranny) and combined with the 3.36 would lower the revs so much on the highway that the L20B may not have enough power to even push the wind out of the way.

 

Just my opinion, but 3.90s or even 4.11 would put some sudden quick revs into the lower gears and the over drive would lower the revs at cruising speed and save a bit of gas. I have an R-180 4.375, (sorry it's sold) now that would move!!!

[pope_face]

My truck has a 4.88... ^_^

 

I would go with the 3.70... my Explorer had a 3.73 with a four-speed auto with O/D and it wasn't too bad... sat at around 1,750 rpm at 100 km/h. No idea what the transmission ratios were...

 

If you really want to get technical on which ratio to use, then do a search on google for a top speed calculator, but use it to find the final drive instead. All you do is put in the speed you want to run at on the highway, the rpm's you want to be at, your transmission ratios, and your wheel size, and it'll find the best final drive ratio to fit. You won't get a hell of a lot of top speed out of it, but it'll be good enough to run on the highway with enough power to kick around town.

[datzenmike]

One thing.

 

You have to take into consideration the engine's ability to push the car along. It takes 4 times as much power to only go twice as fast. Or 4 times the hp at 30 MPH to go 60MPH!

 

3.36 gears are very low and you could find that the car won't have the power at the cruise RPM to keep the speed up. Your foot goes further and further to the floor and actually you can go faster in third than fourth. This is called a power limited top speed.

 

You say you don't want a slug on the street so go with the 3.70, higher if you can.

[datsun dreamer]

I got 3.70's on my '74 with a 4 speed and I'm very happy with them:D.

[Fineline]

Definately 3.70's

[zerow]

It looks like the ayes have it - 3.70s for me. Now to pull the set for the back of the 610... Anybody want to buy a good set of 3.36s...?