Limiting factory of the m44 motor?

[nukeduster]

I'm just curious if anyone here knows the internals of the m44 very well...

Question is, after studying the dyno curves that engine has to have quite a bit more potential waiting to be released... at higher rpms.. I want to raise the redline to more around 8000 - 9000 rpm and maybe re-do the intake manifold to accomodate the greater airflow, maybe short velocity stacks with ITB.

I'm wondering what the weak point is on the motor, what will fail at the higher rpms which need to be addressed?

Forged pistons, and a balanced crank obviously.. and a lower lift longer duration cam.. other then that, any advice? Previous experience? Valve float a problem, need higher spring rate valve springs? etc. etc. etc...

[theironm0nk]

Have the engine balanced it adds a good 50hp maybe a port and polish a good 10-20 hp

[mikester328]

sorry for being the newb on this thread, but what is balancing the engine? the engine only has about 140 hp to beging with (if i'm not mistaken..)

Mike

[BMWjesterFAN]

I'm pretty sure the M44 already has forged internals. I could be wrong though... As far as the engine itself goes, why not bore it and drop some larger pistons in? Then slap the Downing Atlanta supercharger on and Wheeee!

[theironm0nk]

balancing an engine means you balance the weight of the componants so they move more consistantly, smoother and faster.

[BMWjesterFAN]

Right. I get the balancing part. I'm deeply considering balancing and blueprinting my S50. If you have some basic mechanical skills and access to some precision measuring tools, you can blueprint your own motor, as long as you have a machine shop to do work if you need it. Lot's of good books available on the subject.

[theironm0nk]

To my knolleg the m42 and m44 engine has forged internals. But they are not fully balanced. To balance what is done is they polish the surfaces carfully removing very small amounts to balance the parts. This should be done by a reputable proffesional. One misstake and you will need new parts or get a bad running engine.

port and polish means they make the ports bigger but don't make the valves bigger. They then polish the internals and reshape them to improve combustion.

These are actually best done to a 1.8L M42 engine because it increases the power with out going over 1.8L allowing you to compete in the 1.8L division in motorcross and autocross. Doing both brings the engine to about 190-200hp I will have my car dyno soon but can't get print out or else my friend can't do it for free.

Giving an engine a bore or a superchrager or turbo weakin the engine which should only be done if you intend on making a race only car.

[BMWjesterFAN]

I don't completely agree with the boring/turbo/supercharger comment, but oh well. As far as balancing goes, does anyone know if you can knife-edge a crankshaft, while keeping it balanced? I mean, is there a specific weight that the crankshaft has to be, or can it be less than a stock one, as long as it is balanced properly? I'm just wondering if I can get my stock crankshaft knife-edged and balanced, or if I have to have a custom crank made.