Author Topic: rev limiter (Read 5654 times)

pappouszx6r · « **on:** October 05, 2009, 08:45:55 AM »

Hi to everyone!!!
I am new to the club and i want your advice.
At what rpm can a normal m42 (with stock valve springs, valves and retainers) can run without any problems?

bearsbmw · « **Reply #1 on:** October 05, 2009, 11:14:03 AM »

NA 6800rpm and you start loosing power
FI 7000rpm is power limit

this is based on stock internals

pappouszx6r · « **Reply #2 on:** October 05, 2009, 11:39:01 AM »

I am planning to replace the chip on the ecu so i want to know where is safer to set the rev limiter.
Hope that the chip will work so i won't run out of power at high rpm.

Warsteiner · « **Reply #3 on:** October 05, 2009, 01:22:28 PM »

FYI: There is an Instructor that I run with and he has a stock M42 internals with DASC and revs the thing to 7500rpm all day long and has been for years!

pappouszx6r · « **Reply #4 on:** October 05, 2009, 01:44:11 PM »

That sounds good! Anyone else who has tried it?

bearsbmw · « **Reply #5 on:** October 05, 2009, 02:45:18 PM »

Quote from: Warsteiner;79436

FYI: There is an Instructor that I run with and he has a stock M42 internals with DASC and revs the thing to 7500rpm all day long and has been for years!

sure you can rev to 7500-8000 all day long but that won't give you anymore power when the valves are floating... After 7000rpm its the momentum of the crank and the high power you made in the low rpms

It costs big bucks and major valve train upgrades to make power in the high rpms

This only applys for the M42 and the research I have done... I know nothing about any other bmw engine

fscalise · « **Reply #6 on:** October 06, 2009, 12:40:40 PM »

Hey guys what is the best rear end for my 1991 E30 with M42 and stock internals, chipped with ram air. I want more low to mid power.

bearsbmw · « **Reply #7 on:** October 06, 2009, 01:18:22 PM »

If your not worryed about fuel economy I would hit up the 4:10 I have a 3:45 LSD in my turbo and like it

xwill112x · « **Reply #8 on:** October 07, 2009, 04:27:50 PM »

Quote from: fscalise;79501

Hey guys what is the best rear end for my 1991 E30 with M42 and stock internals, chipped with ram air. I want more low to mid power.

4:45

i think you can get the diff ring set out of a 318 vert?

bwawuz02 · « **Reply #9 on:** October 07, 2009, 06:04:37 PM »

Quote from: xwill112x;79564

4:45

i think you can get the diff ring set out of a 318 vert?

or an automatic E36 318

deekay · « **Reply #10 on:** October 07, 2009, 06:12:10 PM »

318 vert 5spd has 4.27... at least, mine did until i swapped in an M3 diff.

318 vert auto is probably a pretty damned rare car, unfortunately.

pappouszx6r · « **Reply #11 on:** October 10, 2009, 08:09:12 AM »

Quote from: bearsbmw;79448

sure you can rev to 7500-8000 all day long but that won't give you anymore power when the valves are floating... After 7000rpm its the momentum of the crank and the high power you made in the low rpms

It costs big bucks and major valve train upgrades to make power in the high rpms

This only applys for the M42 and the research I have done... I know nothing about any other bmw engine

So you think that with a high flow intake and a proper managment you can't get power after 7000+ rpm?