6 Speed Swap?

[Digitalwave]

Your top speed has more to do with your gear and differential ratio from what I understand. The higher the diff ratio the faster your acceleration is but your top speed is lower - the lower the diff ratio the higher your top speed is but your acceleration is slower.

Not necessarily. A 4.10 has a higher top speed than a 3.73 in a stock 325i. The gearing allows the engines power to be used more efficiently against the terrible aerodynamics of E30's.

[RobertK]

I stand corrected..

So I know this is way off topic sorta.. but what is the top speed of a 325i?

[rs4pro3]

IF you wanted close gear ratio's just go for one of the Euro dogleg E30 boxes. A lot cheaper and will bolt right in.

[KenC]

IF you wanted close gear ratio's just go for one of the Euro dogleg E30 boxes. A lot cheaper and will bolt right in.

You can find them for about a grand on s14.net usually.

[RobertK]

Bolts right up eh? Is it a Getrag as well?

[erik325i]

I would prefer it just for the closer gear ratio.

From what I've read, the Euro 6-speed found in the e36 m3s, are not close ratio. The first 5 speeds are pretty much the same. The 6-speed is just an extra high gear, probably to help gas milage.

Here are the numbers:
euro 3.2L 6 speed----------US 5 speed
4.23 ---------------------------4.20
2.51 ---------------------------2.49
1.67 ---------------------------1.66
1.23 ---------------------------1.24
1.00 ---------------------------1.00
0.83 ---------------------------