I just got done pulling the 904 out of my 72 Cuda and putting it back in after a torque converter change. Then I fall upon a 904 with the low gear set. Would it be easier take the gearset out and intall it in the tranny in the car now or just replace the tansmission. I can pull it without removing the headers, but still have to do everything else, headers back etc.
EDIT: The tranny in the car now was completly gone trough last summer and the new one has to be gone trough before installation.

either way, you'll need to R&R the tranny again. just run what you got, and leave the other tranny for your next project.

I had a low gear set in an '83 cordoba 318/904. It was just a daily driver but I did not notice any great advantage with the 2.74 vs the std 2.45:1 ratio 1st gear in how it took off.

Depending on your intentions with the car I doubt that you will notice a whole bunch of difference and not worth the time and effort involved. Rebuild it and have it ready for next time and drive what you have in it.

I have 3:23's in now and want a little more umph in the low end. I have a set of 3:55's and like the low end umph with them. But I would like the 3:55's with the mileage I get with the 3:23's. Would I be close with the 3:23's and low gearset?? I'm in northern Maine and still have at least a month to go before hitting the road so I have time to do the work.

3.23 X 2.45 = 7.9135. 3.23 X 2.74= 8.8502. 3.55 X 2.45= 8.6975. 3.55 X 2.74 = 9.727. You could pull your trans & R&R the front pump & a bit more & add the low gear set & you're all set.

So, if I leave the 3.23's in and change to low gearset I will have basicaly the same as a 3.55 off the line thru 2nd with the same mileage as the 3.23????

I Think the low gearset is a BIG plus in a car with 3:23 or 3:55 gears. It will give you the equivalent of a 3.61 or 3.97 gear on launch. For optimal 1/4 mile times you will shift 1-2 a bit higher than 2-3.

You could think of it as a half step to an OD trans with a .80 OD ratio (and the same overall launch ratio).

make sure you know if one is lock up or not

tc will not interchage with them

I allways get a stock high stall lock up tc for mine with the low gear sets

I would rather have non lock up for hot rodding them

but the lock up will deff help MPGS with the 3.55s

run it till she then slam the other one in and save the time and $ for now...

The low gear set has a lower second as well
2.74 1.55 1
vs
2.45 1.45 1
My GTX gained about a tenth or a little more