M42 engine mods...

[ClbSprt ti]

I really want some more usable power out of my ti. Is there anything else to do (without FI)? Does anyone make underdrive pulleys for the engine? Of course i could do an inline-6 swap, but i think that would really disrupt my weight distribution. So i guess the question stands, what are the best bolt ons for the m42.

[unban vb pls.]

I doubt it will disrupt your weight distribution that much.
you probably look at mostly 60:40 f/r, that's still not bad.

bolt ons probably can give you no more than 10 rwhp

[my318is]

cams, multithrottle intake, custom pistons, displacement to 2.1 liter, underdrive pulleys, chip, tuning software, differential, light wheels. hmm im sure theres more but i cant think right now

[unban vb pls.]

displacement to 2.1 liter, I have heard that long ago, but I doubt
anyone here has done it before...it is done by ACS or sth?

[my318is]

Originally posted by unban vb pls.
displacement to 2.1 liter, I have heard that long ago, but I doubt
anyone here has done it before...it is done by ACS or sth?

A guy on my old board did it. he has somewhere around 220hp at the crank.

[my318is]

BTW doing that would be WAY more expensive than getting a swap or going FI.

[E30 Stu]

Yea, when you are talking about doing cams, 11:1, multi-throttle intake, etc, that is just spending too much money and not getting much power. The M42 already has hot cams (240/240), plenty of head flow, an excellent exhaust manifold/system.

Your best bet is to do an engine swap, for a 2.5L or 3.0L M50.

One thing you CAN do is change out your intake manifold for one off a '91 M42 motor. I am pretty sure it fits yours, and it flows a LOT better. BMW put a choker of an intake manifold on the M42's after '91 and it kills the power above 5500. Looking into finding one off a '91 318is or '90-'91 318i.

[Aaron318iS]

do the '91 cars use the same intake manifold as the e30 318is?
the e30 version looks to be better flowing..

would you mate the intake manifold to ur current throttle body?

[ClbSprt ti]

Originally posted by E30 Stu
One thing you CAN do is change out your intake manifold for one off a '91 M42 motor. I am pretty sure it fits yours, and it flows a LOT better. BMW put a choker of an intake manifold on the M42's after '91 and it kills the power above 5500. Looking into finding one off a '91 318is or '90-'91 318i.

does this really make a difference? does anyone know for sure if it fits?

[E30 Stu]

The manifold should fit. I think it will bolt right up to your t-body too. It flows a LOT better than the later style, dual-stage manifold. You MIGHT lose a little low-end, but the gains over 5000 are immense.

[my318is]

Originally posted by E30 Stu
The manifold should fit. I think it will bolt right up to your t-body too. It flows a LOT better than the later style, dual-stage manifold. You MIGHT lose a little low-end, but the gains over 5000 are immense.

How much gain are we talking.. Is this something you could score from a local junk yard?

[ClbSprt ti]

bump

[E30 Stu]

Originally posted by my318is



How much gain are we talking.. Is this something you could score from a local junk yard?

Yea, be sure to get one off an E30 318i/S '90-'91. Probably a good 10-12 hp above 5500 rpm, assuming you have a chip.

[Aaron318iS]

i must investigate! sounds like an interesting upgrade

question though, if it gives 10 - 12hp, why isnt the e30 twin cam have more power than the e36 version??

[E30 Stu]

Originally posted by ABX-18Z
i must investigate! sounds like an interesting upgrade

question though, if it gives 10 - 12hp, why isnt the e30 twin cam have more power than the e36 version??

It does. BMW rated it at 134. It's not 134. I am sure a '91 M42 will put out about 140-143.

I raced a friends '92 (maybe 93) 318is when I got my '91. Mine was stock, his had a chip, isolated cone filter, and exhaust.

By the top of third I was 15-20 feet ahead of him. The '92---> manifold just does not pull up top (where it needs to).