My 2.8 M20 Budget Overview

[burtonownz]

Don't let people sway you from what you came up with. Make the revisions needed, get some used parts, and build an awesome engine. A really strong N/A engine would be a welcome thing. I was looking to something similar to the M20 before but I've since switched to wanting to work with the M42 in the 318iS.

One thing I can try to encourage is to use Haltech engine management or, if you want to spend more money, MoTeC.

Good luck,
Charlie

[MR 325]

Jon, that's way too much money man. You should spend no more than 3k on a NA M20 motor.

Anything above that, do an engine swap. A shop will do it.

PS. Where's my stickers!!!

[Ryan Stewart]

Chris had the idea with the high flow head. You are going to need a lot of headwork to see real HP gains from higher displacement. The regular 2-valve head would struggle to fill 70% of the cylinders with clean air at WOT.

you would gain some torque though.

The only reason I could see spending that much on an M20 is to build it for 30lbs of boost. Other than that the "headaches" of a regular M50 swap are not enough to scare me away. Except for some of my more complicated choices in doing things the dam thing has been pretty straightfoward.

[rwh11385]

The only reason I could see spending that much on an M20 is to build it for 30lbs of boost.

:up:

I want a ride in a E30 M50 to get a sense for the feeling, etc. Maybe Zionsville Autosport knows someone nearby with one I could catch a ride in.

But anyway, I like the M20B25, if boost only magnifies the power and experience, that would be what I would really be interested in.


With the debates on the board, NA M20s Strokers have pretty much lost out to either Turbo M20s vs. Motor Swaps. I think you could use your desire to keep the M20 and turbo that bitch. The 325i is perfect for it already. Maybe throw in a 524td crank as well, etc, but might not be worth it really.

[MR 325]

I'm gonna go the turbo route on mine. In the process of reading up on it and everything I need right now. Should have the cash next month so I can get started. I should be spending $1000 or less for a simple setup. And I'm gpnna replace the rod bearings and main bearings while I'm at it, along with the clutch.

[Matto]

The only reason I could see spending that much on an M20 is to build it for 30lbs of boost.

:up:

I want a ride in a E30 M50 to get a sense for the feeling, etc. Maybe Zionsville Autosport knows someone nearby with one I could catch a ride in.

But anyway, I like the M20B25, if boost only magnifies the power and experience, that would be what I would really be interested in.


With the debates on the board, NA M20s Strokers have pretty much lost out to either Turbo M20s vs. Motor Swaps. I think you could use your desire to keep the M20 and turbo that bitch. The 325i is perfect for it already. Maybe throw in a 524td crank as well, etc, but might not be worth it really.

Why not turbo a stroker? 2.8 boosted!

[rwh11385]

Sure, but $. If you go with a larger crank, you will need to work on the pistons somehow to make it work.

Does anyone know what Super Eta pistons in an I block and I head and eta crank yields as far as CR? That would be a decently cheap stroker for a turbo, if the CR was decent.

But 2.8i turbo would be expensive, to say the least, but look at Matt325is's ride. It is a fucking beast.

[EverWiser]

One thing I can try to encourage is to use Haltech engine management or, if you want to spend more money, MoTeC.

Why not a Mega-Squirt controller setup? It is DIY intensive but from my comparisons it's very similar to the Bosch setup in that it is a "batch" injection controller. It uses a MAP sensor in conjunction with your O2, TPS, and coolant temp sensor to tailor your fuel curve(s). With the MAP you no longer have to have the restrictive AFM and I'm sure you can eliminate some or all of the ICV system for a simpler "air bleed" for idle speed. Just my .02...

[92 mtechnic cabrio]

The only reason I could see spending that much on an M20 is to build it for 30lbs of boost.

:up:

I want a ride in a E30 M50 to get a sense for the feeling, etc. Maybe Zionsville Autosport knows someone nearby with one I could catch a ride in.

But anyway, I like the M20B25, if boost only magnifies the power and experience, that would be what I would really be interested in.


With the debates on the board, NA M20s Strokers have pretty much lost out to either Turbo M20s vs. Motor Swaps. I think you could use your desire to keep the M20 and turbo that bitch. The 325i is perfect for it already. Maybe throw in a 524td crank as well, etc, but might not be worth it really.

Why not turbo a stroker? 2.8 boosted!

That's what I'm doing. 2.8 stroker now. Then in december, change the pistons and what-not so that I can boost it, up to 16psi or more, depending on how strong the engine will be, then.

[Digitalwave]

So you are going to buy 2 sets of custom pistons, and rebuild the bottom end twice within 4 months? Wow.

[rwh11385]

Forget changing pistons, just go low-comp now and wait for the turbo. It's what Matt did. Why waste time and money changing the pistons, etc. The response may suck with lower compression, but deal with it.


"Pics, the low figures are from last year when it was a 2.8l low compression, with 19lb/hr injectors and NO TURBO."

153rwp would still be okay, and you could deal with that!. but.......

266.50 rwhp , 273.11 rwtq

319hp and 327tq at the crank.

He ran 10psi, and moved to a 3" exhaust I believe, since that was only 2.5"

And well, Matt has had lots of trials building his stroker turbo, but I mean, it's got real balls. He was running at 21psi for a while, but after figuring out the cam timing was retarded (i believe), 15 psi feels faster than 21 did.

I don't know of a recent dyno, and that time he always was faced with problems coming up, but that engine is nucking futs!

[92 mtechnic cabrio]

well, hopefully, all I'll have to do is buy new pistons, but with the kind of job I will be getting over the summer (plus the profit I make selling my school car), and the money I make at school, I have an excuse to spoil myself when I drive my car :D

besides, a year and a half or so is a good enough time to run on high-comp pistons

But I'll take your thought into consideration, it would be a waste of perfectly good high-comp pistons...

[EverWiser]

Not if you sell the high comp pistons to someone who is not looking to turbo their engine in the future...Recoup some of your cash for the rest of the project. Just my .02.

[burtonownz]

One thing I can try to encourage is to use Haltech engine management or, if you want to spend more money, MoTeC.

Why not a Mega-Squirt controller setup? It is DIY intensive but from my comparisons it's very similar to the Bosch setup in that it is a "batch" injection controller. It uses a MAP sensor in conjunction with your O2, TPS, and coolant temp sensor to tailor your fuel curve(s). With the MAP you no longer have to have the restrictive AFM and I'm sure you can eliminate some or all of the ICV system for a simpler "air bleed" for idle speed. Just my .02...

Using the MoTeC M4 system and the alpha-n method would be kick-ass for an N/A car, especially if a lot of money has been put forth to high performance.

[iXer]

Why not a Mega-Squirt controller setup? It is DIY intensive but from my comparisons it's very similar to the Bosch setup in that it is a "batch" injection controller. It uses a MAP sensor in conjunction with your O2, TPS, and coolant temp sensor to tailor your fuel curve(s). With the MAP you no longer have to have the restrictive AFM and I'm sure you can eliminate some or all of the ICV system for a simpler "air bleed" for idle speed. Just my .02...

MegaSquirt is getting better..

The MS-II upgrade processor is very close, read this update:

http://www.msefi.com/viewtopic.php?t=2993

About MS-II:

http://www.megasquirt.info/ms2/

/Mattias