paulmoore

Ok, I currently have a WC T5. I understand that it has a 2.95 1st gear with a .63 overdrive(5th gear). I will either be installing 3.73 or 4.10/4.11's when I get my rear end built. I was doin some thinking today and I just wanted to throw this out here and see what you guys think. If I took my 2.95 first gear, and multiplied it by the rear end ratio of say 4.10 I would have an efective 1st gear drive ratio of 12.10. With 3.73 it would be11.00. Now, if I were to take the 1st gear ratio out of the V6 T5 which has a 4.03 1st gear, and and run a higher(numerically lower) rear end gear, could I still keep the same acceleration rate in 1st but have the benefits of lower engine rpms at cruise? If you plug the V6 1st gear into the above math, I could run the 4.03 1st gear and a 2.73 rear end ratio, and have the same effective 1st gear drive ratio as the 2.95 1st gear with 3.73's. Not to mention that my engine rpm would be low 2.73x.63=1.72 final drive ratio for the highway. Is this feasible? The only drawback I see is that my tranny is a WC and I don't know if the V6 tranny were WC units. Any input/suggestions are welcome. Thanks, Paul Moore

rjmcgee

The ratios from 1 -4 in the V6 box will not be spaced as good as the V8 box. I have 4.10's and a T5 and I think that they work great together, infact I wouldn't want to cruise at a lower RPM on the highway because the engine doesn't really want to work well there. With the 0.63 overdrive you can run alot of gear in the back.

greezemonkey

iTrader: (14)

I`m thinking that v6 1st is gonna wind up like a FARM ALL even with a 2.73..that of course being behind your 8 cyl

dr1

unless your going to be able to get traction, you could be doing as much harm as good
something to think about

gmgod

I believe the v6 boxes are also weaker, that coupled with the super wide ratio of gears 1-4 would be enough to steer me away from it.

paulmoore

Well, if I were to do this, I would only use the 1st gear from the V6, and put it in the V8 box. As for traction, the V6 1st gear 4.03 with 2.73's in the rear would have the same traction and acceleration capabilities as a V8 1st gear 2.95 with 3.73's.

rjmcgee

If that is even possible than you will have a huge gap between first and second. Just use the V8 box and get the gears you need in the rear.

Sonix

iTrader: (1)

Not to add anything helpful here, but I recently made an excel spreadsheet that you can input your tire size, gear ratios, diff ratio, and it'll give your speed in kmh (or I guess MPH) at RPMS.
I saw your post and thought you may want it, lemme know if you want it. -J

paulmoore

sure, that would be great. Only problem is that I don't know the gear ratios for 2nd and 3rd. I know that 4th is 1:1.

Rustydawg

I'm running the V6 gearbox behind my 292, I wouldn't recommend it at all.

Granted, you get lots of torque multiplication in 1st gear, but the gearbox is inherently wide-ratio to help a small, torqueless 2.8 get a relatively large car moving from a stop.

Here are the V6 ratios as far as I know:

4.03
2.37
1.49
1.00
0.85

Compared to the relatively tight ratios of a V8 box:

2.95
1.94
1.34
1.00
0.73

With the V6 box cruising in 3rd gear around town (with a 3.42 rear and 25" tire) the engine speed is about 2500 rpm, drop it into 4th and it's lugging along at 1670. That's my biggest beef with the V6 box. Also, the 1st gear ratio is too low except for drag racing - here it works well with a small motor (like an overcammed, bored out 283...)

You'll be reaching for 2nd gear in the middle of an intersection when you pull away from a stop sign, even driving 'granny style'.

The additional torque multiplication of the 4.03 1st gear also makes the gearbox capable of that much less torque handling.

From what I've read on the 5-speeds.com website, the V6 parts will not swap into the 5-speed box. It's a different mainshaft etc...

paulmoore

Well, thanks for the input guys. I was just playing around with the idea in an effort to get better than 8 MPG while still having the ability for tire shredding acceleration.