Author Topic: M42 budget build (Read 11385 times)

P Zero · « **on:** January 31, 2008, 07:33:30 AM »

Hi folks,

I'm in the process of building a track car using a 316 shell and 318is running gear. I need to start thinking about the engine because I think I need to install it early on so its not lying on the garage floor getting in the way :rolleyes:

I have an M42 which is running well and has just had new cam chain, sprockets and tensioners. After speaking to tim_s I think I'm going to go with a 1.9 bottom end to keep the costs down. I also have a set of E36 M3 Evo throttle bodies which I plan on fitting.

I am also planning on swapping out the fan and pas pump for electric versions to try and reduce strain on the motor.

So here come the questions;

Will I have to go with aftermarket management or is there any other way to run this setup using the standard ecu?
Would fitting performance cams see a significant change in performance coupled with the itb's?
What other mods can I make that won't break the bank?

sheepdog · « **Reply #1 on:** January 31, 2008, 11:52:15 AM »

You will need an aftermarket ECU.
Cams will not do much unless you have the heads done up.

Other mids...
I would do coil on plug, not much power, but a good investment. Headwork and new cams will be the biggest help.

On the heads (which are the biggest problem with the engine it seems), clean up the bowls and ports, and unshroud the valve stems. I would also consider tapering the valve stems, and using VW lifters. Then go with Megasquirt or another ECU, raise the rev limit to no more than 7500. Could also raise the compression a full point and switch to a single row timing chain. I would also go for a lightened flywheel.

Not 100% sure, but you should be good for 180-190hp. Maybe more if you do it all right.
Unfortunately, you are probably half way to a Metric Mechanic built motor by this point. Pistons are the best spot to save costs, leave the stock 1.9 bottom end.

P Zero · « **Reply #2 on:** February 03, 2008, 05:30:33 PM »

What are the benefits of coil on plug?

hoevesruperd · « **Reply #3 on:** February 03, 2008, 06:39:58 PM »

Quote from: P Zero;42149

What are the benefits of coil on plug?

i think you will get a better spark every time. there is no resistance from the wires so the voltage can be higher at the plug. its almost the same price as performance wires too.

sheepdog · « **Reply #4 on:** February 03, 2008, 10:38:55 PM »

Quote from: hoevesruperd;42155

i think you will get a better spark every time. there is no resistance from the wires so the voltage can be higher at the plug. its almost the same price as performance wires too.

If you are careful, they can be had for less than performance wires and lasts a lot longer. Also cleans up the engine bay a bit.

My thinking though above all is wires are just one more connection to fail, and one more expense you do not need. Do this you replace the coils, and eliminate the wires for the same cost as the wires.

I love simplicity.

P Zero · « **Reply #5 on:** February 04, 2008, 07:39:31 AM »

It would be beneficial for me because I'm converting a 316 to M42, so I have no coil mount on the inner wing.

My other car is a Peugeot 405 Mi16 which has coil on plug as standard. I know that the boots just pull off the coils, so I'll check tonight if the boots fit the M42 coils and are long enough to contact the plug.

koyota · « **Reply #6 on:** February 06, 2008, 01:35:00 AM »

Quote from: sheepdog;42011

You will need an aftermarket ECU.
Cams will not do much unless you have the heads done up.

Other mids...
I would do coil on plug, not much power, but a good investment. Headwork and new cams will be the biggest help.

On the heads (which are the biggest problem with the engine it seems), clean up the bowls and ports, and unshroud the valve stems. I would also consider tapering the valve stems, and using VW lifters.

I am sorry for invading your thread man, but I was wondering which model VW are these lifters from? Can anyone provide the part number? Also can I get a picture of that coil on plug system?

hoevesruperd · « **Reply #7 on:** February 06, 2008, 01:48:41 AM »

Quote from: koyota;42274

I am sorry for invading your thread man, but I was wondering which model VW are these lifters from? Can anyone provide the part number? Also can I get a picture of that coil on plug system?

http://www.m42club.com/forums/showthread.php?t=3698

P Zero · « **Reply #8 on:** February 06, 2008, 07:50:39 AM »

After reading more threads and talking a lot to kowalski, I have come to the following spec;

Overbored block
M44 crank
S52 pistons
M42 rods
Total Seal piston rings
Cams (spec yet to be decided)
VW lifters
S50 springs (unsure on this)
E36 M3 Evo ITB's
Custom plenum
Megasquirt (or other management)

I was hoping for 180bhp originally within a budget of �1000 ($2000). Do you reckon this spec is possible for that money?

Also, can anybody explain to me more about tapered valve stems?

hoevesruperd · « **Reply #9 on:** February 06, 2008, 10:54:51 AM »

i think you will go over budget if you go with mostly new parts
as a reference all in $
here are some pistons and crank for 300
http://www.318ti.org/forum/showthread.php?t=13919
VW lifters on ebay will go for under 100
m42 rods i assume you already have them
new valve springs are aroung 300
ITBS are expensive and hard to find
http://www.dtmpower.net/forum/bmw-parts-sale/103631-fs-e36-m3-throttle-body.html
custom plenum
if you do it yourself, and you do it righ the first time it should be around 50$
megasquit 300
Schrick cams: 900

by the way this is very interesting, i hope you can keep us posted throughout the development and build

swiss318is · « **Reply #10 on:** February 06, 2008, 11:26:28 AM »

interesting thread.. a budget build m42!
i am building two cars at the moment.. it really helps to know where i can save money!

P Zero · « **Reply #11 on:** February 06, 2008, 04:47:31 PM »

Well, I'm in the process of obtaining my M44 crank and S52 pistons from Kowalski on this forum. They are already prepared for use but I'm not sure how much they are going to cost yet due to shipping costs. Hopefully my Dad is going to bring them back from Canada with Him. I already have M42 rods.

I already have a set of E36 M3 Evo ITB's which I picked up on UK ebay for �100 ($200). I already have a few ideas about plenum design, but I reckon $50 is a fair build cost.

S50 springs and VW lifters I can get second hand pretty easily I would hope. Is that a good idea?

If megasquirt is that pricy I might look at some more mainstream alternatives (omex, emerald, etc).

For cams, I was looking at catcams. They do a set for the M42. Not sure on cost yet but hopefully cheaper than schrick.

So it looks like cams and management are going to be the things to break my buget. I'll have to look into some cost saving alternatives.

hoevesruperd · « **Reply #12 on:** March 13, 2008, 09:06:47 AM »

where are you at? any updates on your build?
i found a dead M42 that will serve me to build an engine similar to yours, slowly, while in university next fall

anything you find or development on your side would help me as well, keep me posted

swiss318is · « **Reply #13 on:** March 19, 2008, 02:18:09 AM »

where are the pics of the E36 M3 Evo throttle bodies?? ;-) did you already begun your project?

P Zero · « **Reply #14 on:** April 27, 2008, 06:21:41 PM »

Hi folks, sorry for not having posted any updates, we've been busy buying a new house which needs quite a lot of work, so the IS isn't getting the attention it really needs.

It is progressing slowly though, I was down at the garage all day today cleaning up the engine, although I'm not sure whether to stroke it at the moment due to cost. I'll be making a decision about that over the next week or so.

I now have an M44 crank and S50 pistons (ground down to maintain original CR), so all that would be needed would be an overbore to complete the stroker part of the project. The engine is hanging in the garage at the moment waiting for a decision.