Redtop tranny

[mr220v]

I'm going to start buying parts for my redtop swap in the next few weeks, and need to make a decision about the tranny.

My main problem is that the later 3sge's trannys seem to have a higher final drive than the earlier s54's (its the same as the turbo tranny). I know the UK gen3 3sge mk2's advertised a top speed of 150mph. Unfortunately, the byproduct of this was that the 0-60 was rated at 7.8, whereas the gen2 3sge was rated at 6.8.

Did the redtop 3sge have this same, taller final drive? Seeing as how I don't plan on cruising above 100mph, if the redtop tranny was the same or similar to the gen3 tranny, I will probably just reuse my original 1991 s54. A higher final drive is only going to help my fuel economy, and i'm not getting a beams motor for that reason.

[Roman]

A higher final drive ratio means that you'll be doing more RPMs at a particular speed...

IIRC the early ones had a 3.9 ratio, and later ones had 4.1 ratio.

The 0-100 time is slower because you have to change into third before you get to 100 I think, and the later model cars are heavier too.

I wouldnt be fussed with either, I've got a gen 5 gearbox, and the gears definitely feel shorter than my old gen 1 box. I'd rather have the higher final drive ratio personally, but wouldnt be too fussed either way.

[PHOENIX]

hey Dave, you should do a complete tranny write-up for the beams, there seems to be a lot of questions about what tranny to use if they don't have the gen 5 tranny. It would be really beneficial i think and definatly website material.

Try to cover both the turbo and non turbo trannies, what you need to do to adapt them to the beams, and what parts would be needed.

[mr220v]

Originally Posted by Roman

A higher final drive ratio means that you'll be doing more RPMs at a particular speed...

IIRC the early ones had a 3.9 ratio, and later ones had 4.1 ratio.

The 0-100 time is slower because you have to change into third before you get to 100 I think, and the later model cars are heavier too.

I wouldnt be fussed with either, I've got a gen 5 gearbox, and the gears definitely feel shorter than my old gen 1 box. I'd rather have the higher final drive ratio personally, but wouldnt be too fussed either way.

Its funny you say the final drive for the later 3sge's was 4.1, because the usdm 5sfe tranny had a final drive of 4.1. The usdm ratios were:

5SFE S54
1 3.285 13.718
2 1.960 8.185
3 1.322 5.521
4 1.028 4.293
5 0.820 3.424
Final Drive 4.176

So maybe ratio wise, the two trannies are the same?