Best Mods For M42

[narbar_1234]

Hi, Im new to this forum, my names Dean and i have a 1994 318is and live in England.  One thing ive noticed is that its very difficult to find any decent mods for the good old M42!

What mods would you recommend and where can i get them from?

Thanks for the help!

[sheepdog]

Most mods are low HP, and reliability mods.

Get a tune up, replace all your hoses, o2 sensor. A nice upgrade is coil on plug, there is info about it floating around, costs about the same as replacing the plug wires, but you get coils too. A modded air box is rumored to help the very top end, but it is minor, it does help the sound of your engine. Some guys upgrade to a certain Mustang injector as well.

A chip is your biggest upgrade performance-wise, followed by a lightened flywheel. After that, the return on what you spend becomes pointless. BMW pretty much locked this motor down unless you want to tear into the head, cams and/or bottom end. $$$

There are guys doing budget turbo, blower and stroker setups in though so take a look around. Unfortunately we are not driving small block Chevys.

[1991 E30 M42]

To go along with what sheepdog was saying, the cams are the big limiter of power on this engine and aftermarket cams are expensive. A lightweight flywheel is a great modification for this engine as the factory flywheel weight 29.5 pounds. But with lightweight flywheels you have to take into consideration how streetable it will be. M20 flywheels are very popular and cheaper than going completely aftermarket and they also use a larger clutch.