b25 - what's all the fuss?!

[jimbom30cab]

Yes it will be bags of fun and plenty of fast gear changes.

You might get a little bored of the high engine revs on the motorway though

I'm no expert but when new the 325i models had 3.64 to 3.91 fitted.

Many people say the 3.64 is the best all rounder for the M20B25, the ideal compromise between acceleration and easy cruising.

If your car is a touring you might want a higher number as i believe they are a little heavier and of course are designed for carrying loads.

Perhaps 3.91 would be a nice ratio for a 325i touring.

[HairyScreech]

Around where me and Rog are there are more lanes and country a roads than 70mph roads, most of the a road are 50s or winding so it's less of a busy diff around here.

It must have been a 4.45 I started with then as before my G250box and z3 diff I was on an identical conversion at one point.

[Jesus325iTouring]

Around where me and Rog are there are more lanes and country a roads than 70mph roads, most of the a road are 50s or winding so it's less of a busy diff around here.

It must have been a 4.45 I started with then as before my G250box and z3 diff I was on an identical conversion at one point.

Nail on the head there Hairy, this week i've driven just under 400 miles, all local, 80% of roads were B's or unclassified, and all the while the boot, back seats, fronts were crammed with tools and or children

Not fussed about motorway/dual carriageway speeds and TBH, rarely use them.

Should be fun, glad it was this way around than the other

Happy Rog

[HairyScreech]

For what it's worth, I'v tried a b25 with a G240 coupled to a 4.45, a 3.64 and now a G250 box and Z3 3.15.

The G250+ 3.15 (numerically similar to 3.91) is very similar to the G240 box and 3.64.

The 4.45 was brilliant fun, then the spool cracked and it made awful noises.

The 3.64 was slower than the 4.45 but not by as much as I expected, in the real world you just hung on to a lower gear for longer.

205/50 profile tyres make a 3.64 more like a 3.7.

The 4.45 was fine even at 70mph, just means the engine spins a bit more.

[DanThe]

I think you need more power Jim