Author Topic: Need a bit of help (Read 4171 times)

carlos318is · « **on:** March 07, 2010, 04:21:00 AM »

A friend of mine has a early E30 325i and is wanting to turbo it but has been told the the early E30's you cant do due to a high compression engine and that he should look for a latter E30 325 engine that has low compression how true is this

If you need any more info please ask;)

carlos318is · « **Reply #1 on:** March 07, 2010, 05:27:54 AM »

Sorry I forgot to say its a M20 engine

DesktopDave · « **Reply #2 on:** March 07, 2010, 07:41:56 AM »

Not what I've heard. IIRC both i and e engines are 9:1, except the '88 "super Eta" at 8.5:1.

The really hot ticket is an M20e block with M20i head and electronics. Makes compression ~8.3:1 from what I've heard, perfect for a turbo.

carlos318is · « **Reply #3 on:** March 07, 2010, 09:57:42 AM »

Ok that makes some sence :confused:

So can it be done M20 325I with just replacing the rings and gaskets head bolts and all the normal bits that you would replace when stripping the engine

DesktopDave · « **Reply #4 on:** March 07, 2010, 10:08:11 AM »

You're lucky to be over the pond...all those diesel parts for cheap & easy conversions. I'd suspect a 525tds manifold/intercooler and a rrfpr could make it plug & play. I'll bet the forged crank might be good for a 2.8 liter build too.

carlos318is · « **Reply #5 on:** March 07, 2010, 11:35:32 AM »

So you are saying that it is not as simple as a bolt on job done

WeirdYo2 · « **Reply #6 on:** March 08, 2010, 05:51:01 PM »

All you gotta do it put a new mls headgasket and studs in that can hold 30psi (if you want to run that much). Ive seen it done several times and the engines are fine as long as you tune it right. An m20 motor like that can stand up to more hp than your driveline will be able to.

deekay · « **Reply #7 on:** March 08, 2010, 09:32:25 PM »

the 524td manifold requires you to redrill the bolt holes, i believe.

do some searching on e30tech, plenty of m20 turbo guys there.

e30guydownunder · « **Reply #8 on:** March 11, 2010, 04:25:17 PM »

I would not hesitate to run a 9:1 CR engine with a serious amount of boost. The reason most of the DIYer's run into issues is getting a good tune. With a backyard/road tune you are bound to blow headgaskets, even at 8:1.

Throw a head gasket and studs at it. Turbo it with a standalone ECU of some sort and take it to a dyno for the final tuning. Get the tune bang on and you will be able to boost safely, making good power for a long time.

carlos318is · « **Reply #9 on:** March 13, 2010, 04:12:15 AM »

Quote from: WeirdYo2;89106

All you gotta do it put a new mls headgasket and studs in that can hold 30psi (if you want to run that much). Ive seen it done several times and the engines are fine as long as you tune it right. An m20 motor like that can stand up to more hp than your driveline will be able to.

So it can be done on the old 1987 E30 M20 engine and if wanted you can run 30psi:eek:

e30guydownunder · « **Reply #10 on:** March 14, 2010, 03:45:44 PM »

it would hold 30 for a while. Nobody has really gone above 22psi on a standard bottom end however.