M20 and 2.93 LSD Question

[JCarp90]

I just built a brand new M20 and did the auto to manual swap and I currently have a 4.10 open diff in it. I've got a 2.93 LSD laying around that I'd love to trade for a 3.25 or 3.46 but that doesn't seem to be working in my favor.

My question is how dogshit slow will my car be with a 2.93? Anyone running an M20 with a 2.93 LSD wanna chime in?

[Wanganstyle]

I just built a brand new M20 and did the auto to manual swap and I currently have a 4.10 open diff in it. I've got a 2.93 LSD laying around that I'd love to trade for a 3.25 or 3.46 but that doesn't seem to be working in my favor.

My question is how dogshit slow will my car be with a 2.93? Anyone running an M20 with a 2.93 LSD wanna chime in?

Ive done this with my 10.5:1 2700cc. G260+3.07, 3.15 was all slow as hell

3.46 was more suited, 3.73 is actually perfect (OEM ratio for G260+e30)

[jeffw]

I have the m20b27 on a 2.93 lsd and it isn't too bad. I am auto for now too though

[mcr_driver]

stock m20b25 with a 2.93 is odd not m10 slow but no where near fast...really unless you are boosting on a budget or want mpg's look for a 3.25/3.46

[e30leigh]

why not stick with the 4.1? or get a 3.7? a 2.9 will be a slug. but for all the slow acelleration you will have one killer top speed. if you have the horses to push the car.

as for mpg. long diffs like the 2.9 dont always result in better mpg's they typically require more effort on the engines part to shift the car along, so you tend to have more throttle on, so even though the revs are lower, the engine is labouring more, using more fuel, so the mpg's dont always lower. i find with a proper suited diff like the 3.7 you get better economy. the engine isnt reving too much, its not labouring, so you dont have as much throttle on to maintain speed.

[JCarp90]

stock m20b25 with a 2.93 is odd not m10 slow but no where near fast...really unless you are boosting on a budget or want mpg's look for a 3.25/3.46

Not boosting for now. I don't want a 3.73 because that's still too short. I drive for close to an hour and a half daily on the highway. Like I said, a 3.25 or 3.46 would be idea.

why not stick with the 4.1? or get a 3.7? a 2.9 will be a slug. but for all the slow acelleration you will have one killer top speed. if you have the horses to push the car.

as for mpg. long diffs like the 2.9 dont always result in better mpg's they typically require more effort on the engines part to shift the car along, so you tend to have more throttle on, so even though the revs are lower, the engine is labouring more, using more fuel, so the mpg's dont always lower. i find with a proper suited diff like the 3.7 you get better economy. the engine isnt reving too much, its not labouring, so you dont have as much throttle on to maintain speed.

Have to have LSD. This open shit is not near as fun. The 4.10 sucks - way too tall. I'm turning almost 4k at 75.

[e30leigh]

what does the engine turn with a g260 and 4.1 at 60? as i have a 4.1 in now and plan to have a new m20b25 and g260 in soon and was tossing up what diff t run. i was thinking ill keep the 4.1 and lock it for events like drifting.

anyone know if the medium case comes taller then 3.7?

[bmwguy325is]

what does the engine turn with a g260 and 4.1 at 60? as i have a 4.1 in now and plan to have a new m20b25 and g260 in soon and was tossing up what diff t run. i was thinking ill keep the 4.1 and lock it for events like drifting.

anyone know if the medium case comes taller then 3.7?

http://www.csgnetwork.com/rpmcalc.html

http://en.wikipedia.org/wiki/BMW_3_Series_%28E30%29

[e30leigh]

thanks for the links

[Kogando]

188mm in E30 casing goes from 2.65 to 4.45 (and even higher like 5.00, but those are rare motorsport ratios)

2.93 on a m20b25 is really tall, especially when you want to have some fun with your LSD. When you run a 2.93 you're probably not able to spin the wheels that easy. I would say it's only okay from an economic point of view.

[e30trooper]

327i ( i head swap ) with a open 2.93 You can see wheel spin at 40-45mph thats the end of 1st gear lol. Still had power and great mpg.

[JCarp90]

327i ( i head swap ) with a open 2.93 You can see wheel spin at 40-45mph thats the end of 1st gear lol. Still had power and great mpg.

Did your first gear just go to 40

Fuck you.