4-speed blues

[georgeb]

I've been using Festivas for courier work since '08 or so. I originally used a '93 5-speed but it developed numerous issues and parked it. I bought an '89 to replace it. Driving it home I noticed it wouldn't go into 5th. Because it had none! The doofus I bought it from said it was a 5-speed and I couldn't check it because it didn't have tags. I know now that '89 L's don't have 5-speeds. I do primarily highway driving and this thing sounds done at 65 MPH. I found on this site the ratios. The final drive for the 5-speed is an incredibly tall 2.6: 1 vs. 3.5 for the 4-speed. (Auto is 3.22). 4th is lower than 5th and the final drive on the 4-speed is lower yet! I seriously need some taller front tires or am resigned to driving in the right lane. Mileage is consistently above 40 somehow.

[Safety Guy]

I suppose you could be glad you have a four speed instead of an auto.

One simple partial remedy which should help a bit would be to switch to 13" wheels with 155/80s. They should fit okay if you don't carry heavy loads in the back.

The best solution is to either swap to a five speed or trade the whole car for one so equipped.

Or just buy a five speed for your second Festiva, with your four speed as backup.

Karl

[Charlie1717]

My blue festiva has a 4 speed (although it's a 91 someone replaced it with a 4 speed :s). I've cruised at 75 for hours with it and it does just fine. Really loud but fine. I've been able to get around 45-50 mpg going 75 with my 4 speed

[georgeb]

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.

[htchbck]

You could always yank the 5 speed from the '93 and drop in in the '89. Trans is a direct bolt up. Just my $0.02

[91mcnasty]

Or he could fix the 93 ))

[htchbck]

^^

True, depending on how much this statement is refering to.

but it developed numerous issues

[FestYboy]

I've been using Festivas for courier work since '08 or so. I originally used a '93 5-speed but it developed numerous issues and parked it. I bought an '89 to replace it. Driving it home I noticed it wouldn't go into 5th. Because it had none! The doofus I bought it from said it was a 5-speed and I couldn't check it because it didn't have tags. I know now that '89 L's don't have 5-speeds. I do primarily highway driving and this thing sounds done at 65 MPH. I found on this site the ratios. The final drive for the 5-speed is an incredibly tall 2.6: 1 vs. 3.5 for the 4-speed. (Auto is 3.22). 4th is lower than 5th and the final drive on the 4-speed is lower yet! I seriously need some taller front tires or am resigned to driving in the right lane. Mileage is consistently above 40 somehow.

george, hate to burst your bubble, but the 4 and 5 speeds have the same ratios and final drive (4 spds just missing the 5th). i also have had no issue driving at 70+ for hours in 4th gear in my 89 with 40+ mpg to boot.

[georgeb]

According to a chart I found on this site, the 4-speed has a .9:1 4th and a 3.85 final compared to a 5-speed .69 5th and 3.77 final. That would make the combined final 3.5 for the 4-speed and 2.6 for the 5-speed. (You have to multiply the top-gear ratio by the diff ratio to get the overall final ratio). My '93 factory manual confirms the 5-speed numbers but I don't have an '89 manual.

[drddan]

I agree, the 4 and 5 speeds are different. There are folk here that will argue that, but every 4 spd i've seen runs about 400 rpm's higher than a 5 spd at 60-65 mph. THAT is a different final drive ratio!

[denguy]

Is someone saying that 5th gear is not overdrive, and 4th in a 4spd and 5th in a 5spd will be showing the same rpm at 60 mph?

[georgeb]

According to the Mazda gear ratio chart I referenced earlier, the final drive ratio (not to be confused with the diff ratio) is 2.6:1 for the 5-speed and 3.5 for the 4-speed. Multiplying the top gear ratio by the diff ratio will give you these numbers. 2.6 is 74% of 3.5. Which means that the 5-speed equipped motor only turns at three-fourths the speed of the 4-speed equipped motor at a given highway speed. Or the 4-speed motor spins one-third faster. That means that whatever speed a 5-speed car does at 3 grand a 4-speed car would be at 4 grand. I need to do a swap.

[drddan]

^ X2. Me 2.
65 mph = about 3600 rpm for my Festy.

....and i've got 14" tires too. The 12" run the engine about 3700 rpm!

[FestYboy]

ok i see the math you're doing and it's not wrong, BUT, the 4 speed trans (not including the Cali only early production models, which is where you're getting your odd numbers) have the same 1-4 gear ratios and final drive as the 5 speed trans. all the 5 speed does is add another gear to the 4 speed box. since you have an 89, you have the "standard" gear set in your trans and if you wanted to, you could take the input and lay shafts from a 5 speed trans (lay shaft contains the pinion gear as well) and slap it in your 4 speed trans WITHOUT changing the diff. (just need to add the 5 speed gate as well to allow the shifter movement).

[drddan]

Where is your proof of this, and the "early" california models?

I have an 88 4 spd, that was a midwest model all its life. NOT california.
It runs 400 rpm's above any 5 spd iv'e ever seen at 65mph. As a matter of fact, I have never seen a 4 spd that didnt. Every 4 spd i've seen has run higher rpm's than a 5 spd, on the highway.

5 spd = around 3200 rpm's
4 spd = around 3600 rpm's

Damkid has posted the ratio's on this forum, and it shows different final drives for the 4 and 5 spd's.
Show me a chart that backs up what you are saying.

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.

That also would mean there were 3 different manual tranny's made for the festiva, and I have only seen proof of 2.