Low end torque

[michael1972]

I searched other forum and couldn't find my ansewer so I am asking all of you. What would I have to do to the rear diff gear ratio and what would I need to buy for parts to do it to get more low end torque/ accelartion out of my e46 M3? It pulls like a beast in the higher revs. But I want to know if theres a way to get more power around 3-5000 range. Thanks.

[B C]

http://www.turnermotorsport.com/p-2052-e46-m3-differential-upgrade-custom-options.aspx

A twin-screw supercharger is another option.

[jmo69]

Afterburners? 

[Jeff]

Tuning it some. Nitrous when you get to 3k rpm.

I'm seconding the twin screw though.

[straight6pwr]

all that work for 1st gear 3-5k acceleration? thats really the only time you cant help but have the revs low if you are driving fast.

[Brian.]

I don't think he said first gear pulls Dan, haha.

But like they mentioned, a 4.10 LSD is your best bet. BMW's are geared really high in the lower gears (1-4) my BMW can do 50 in first gear..

But a 4.10 LSD will definitely help you with getting a good launch, and low speed/RPM rolling starts as well.

[Brian.]

And if you do go through with that turner motorsports differential upgrade, It'll get pricey quick, but you'll definitely wreak benefits, if you go with a 4.10 or hell even a 4.45 gear ratio.  On top of that, I'd step up the limited slip type, and go with a Quaife helical (additional $1,200) OR the 3 clutch.

 

It's one of those things many people over look when building up a car. (I've recently been studying rear diff *lsd especially* and learned alot) even building up an LSD's limited slip style, can be the make or break on the track. And rebuilds of it, can be that much cheaper if you go quaife, or a TSM's 2-3 clutch type.

[straight6pwr]

I don't think he said first gear pulls Dan, haha.

But like they mentioned, a 4.10 LSD is your best bet. BMW's are geared really high in the lower gears (1-4) my BMW can do 50 in first gear..

But a 4.10 LSD will definitely help you with getting a good launch, and low speed/RPM rolling starts as well.

 

he didnt say first gear pulls, but thats the only time where he has the excuse of not keeping the revs up.

also, lowering the gearing may actually give him more torque between 3-5k, but since its also going to give him more torque between 5k-redline, he will still feel the same burst.

changing torque/power curves and getting low end involves tuning the motor, whether its cams, engine management, FI, etc.

[Brian.]

he didnt say first gear pulls, but thats the only time where he has the excuse of not keeping the revs up.

also, lowering the gearing may actually give him more torque between 3-5k, but since its also going to give him more torque between 5k-redline, he will still feel the same burst.

changing torque/power curves and getting low end involves tuning the motor, whether its cams, engine management, FI, etc.

 

 

Your last 2/3rds is spot on. To get a lower power band, (BMW's are notorious for the higher end power band) You're gunna need cams, a custom tune, and forced induction would definitely help. hell, even a low, 4-5PSI on the E46 M3 motor, would wreak gains as well.

[KaiserRolls]

Your last 2/3rds is spot on. To get a lower power band, (BMW's are notorious for the higher end power band) You're gunna need cams, a custom tune, and forced induction would definitely help. hell, even a low, 4-5PSI on the E46 M3 motor, would wreak gains as well.

 

get the purple power band, its best for most horsepowers. 

[Brian.]

get the purple power band, its best for most horsepowers. 

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Actually purple is the lowest. vibrant yellow is the best.

Just kidding, but for an E46 M3, boosting that, or any custom tuning or cam kit, is gunna be pricey!