4-speed blues

[georgeb]

I see what FestYboy is saying. That there is a later 4-speed that had the same ratios as the five speed up to the OD gear that it lacked. Having the same diff ratio with different top gear ratios would not produce the same result. The chart I looked at must have the numbers from the earlier 4-speed.

[crazyrog17]

Auto gear is taller than 4-speed (3.22 vs. 3.5). '93 is the one with the scored snout issue. Also have '92 auto eligible for historic tags (MD) Jan '12.

After torque converter losses, it should be about the same.

A transmission can gear the the trans 1:1 on an automatic but it doesn't come out 1:1 at the wheels.

[htchbck]

It doesnt even make sense to add a 5th gear and still have the same final drive. The whole purpose of adding another gear is to lower the rpm's to improve gas mileage.

I don't think you understand the concept of the gears and final drive. I will let FestYboy explain it if he wants, since he is the one you are having the discussion with. If he doesn't, then I'll probably jump back in here and try to set it straight

[roycehof]

Folks, I have had both of these apart. The 4 and 5 speed have the identical gearing for first through fourth gears. The 5 speed has another gear set that give it an "overdrive" which will drop the RPMs down some at highway speeds. I had a 4 speed in my car while I rebuiilt my 5 speed and there was only a slight difference in mileage (I drop about 2 MPGs) and it was slightly louder (due to the engine revving higher). The car had no problem burying the speedometer (85 MPH) with the 4 speed in there and cruised comfortably at 75. If you are having trouble holding speed with the 4 speed, it isn't because of the transmission. Have you replaced your fuel and air filters lately? Perhaps it isn't getting enough fuel or air? The earlier posted suggestion of puttiing the 5 speed in is excellent - these are really simple cars to change transmission in (the 4 and 5 speed are interchangeable). The car likes the highway a lot better with the 5 speed in it.

[georgeb]

If what those who have been inside both gearboxes say is correct, then the final drive ratio of the 4-speed would be 3.24:1 (top gear X diff ratio) which is better than 3.5:1 using the chart figures. Which would mean that a 5-speed car runs at 80% RPM of a 4-speed in top gear. (4 grand vs. 5 grand).

[FestYboy]

^ you're still confusing lol

ok guys, when i or any other car guy talks about the final drive, they mean the diff ratio and ONLY the diff ratio. don't mistake that with final gear ratio, which is the result of multiplying the selected gear ratio and final drive ratio.

also, BOTH 4th and 5th gears in either trans (4th in a 4 speed and 4th and 5th in a 5 speed) are overdrive gears (they are below 1.00:1 BEFORE the diff gear). so, the 4 speed IS an overdrive trans.

drddan, go to a factory 89 manual and in the trans section, it will list the ratios for both the 4 and 5 speed boxes (which are the same) and will also list the SAME diff gear for BOTH trans. the early trans i speak of is the one listed in damkid's graph and was only a cali model (so far as we can tell) and was only available for less than the first 6 mos of sale in the US (cali got the festy before the rest of us and the very early production numbers were the ones to get that trans).

is it possible that the trans in your car came from an early production car because the original was replaced?

[roycehof]

Putting all the gear ratio talk aside - Your car should have no trouble traveling at highway speeds with a four speed. If you are having difficulty keeping speed on the highway, you may another issue going on, but it isn't the fact that you have a four speed instead of a five speed. Trust me other than making more revs (and some more noise), a Festiva with a four speed is comfortable cruising at 75 (and even higher). You should make sure that the engine is getting all the fuel and air it needs and that the exhaust isn't restricted. These engines LOVE to rev and make good power above 3500 RPMs. They are Mazda engines after all - you know - ZOOM ZOOM!!

[FestYboy]

^ correct! and since you have a carbed engine, you have no rev limiter = 7500 rpm shift points!!!

[georgeb]

My 4-speed '89 will go faster than 65 no problem. I'm just used to a 5-speed. 65 MPH is about where I would shift into 5th. It just sounds like I'm ragging on it above 65.

[drddan]

is it possible that the trans in your car came from an early production car because the original was replaced?

I have the original papers on this car. It has been a Missouri car all its life, the tranny has not been changed. I am the 2nd owner!

^ correct! and since you have a carbed engine, you have no rev limiter = 7500 rpm shift points!!!

I have hit 7000, but dont like to. My engine is old, and has blow-by. It still runs great, but I am starting to baby it 'till I rebuild another B3 for it.
I fly up hills at 75+ mph, 'cause the B3 does like the higher rpm's for torque.
I want to drop the rpm's for cruising with a 5 spd. I would have no problem shifting to 4th for steep hills.

[IdealSociety]

I have had two differently geared 4spds, the best mileage i ever got from a festiva was from a 4spd (52mpg pretty consistently on the highway).

i would assume it was the cali model though since the other 4spd cars i owned never made the same returns. pretty sure it was an 88 or 89 LX.

other than that i cant tell ya much, i dont tend to keep festiva transmissions/motors in my cars long

[FestYboy]

All the LX models should have 5 speeds in them. all other 88-89 manual cars would have the 4 speed from factory.

[IdealSociety]

may have not been an LX then, its been probably 9 years since i had that car

another possibility would be that somebody changed the trans gearing before i purchased it too.

[litesong]

Trees

Trees aren't kind to me...

You're right.............

http://www.youtube.com/watch?v=6ucahb5GGeo

[litesong]

Trees

Trees aren't kind to me...

You're right.............

http://www.youtube.com/watch?v=6ucahb5GGeo