my 24v build, slightly different than the norm. Now with dyno numbers!

[2mAn]

Hey all, recently my 2.7i died due to a cracked head. I searched for a 885 head for a while and finally decided I was going to go 24v. I'm from Nor-Cal so I wanted something I could BAR if I decided to move back. The idea is that the motor will appear like a M50 Vanos from an E34. The motor is a different beast alltogether. Here are the specs of what my tax return got wasted on:

-Aluminum Block M52B28
-AKG motor mounts, E21 trans mounts & AKG alum cups.
-S52 Cams
-S52 Exhaust Manifolds
-M50 Intake Manifold
-M50 Vanos Wiring Harness from a E34
-Red Label 413 DME with a TMS chip for a M50 with S50 cams
-3.5" MAF
-Pinktop Injectors
-M42 Radiator with electric fan setup.
-E34 Airbox

Car its all going in is a 1984 318 that already has the C101 from a 87 iS along with the aforementioned M20. Weighed the car with a full tank of gas when I first bought it and it weighed in at 2560 with me, and Im over 160lbs :) As far as the transmission side of things goes, I am keeping the G260 and the S3.73.

The cars thread is here

I will update this as I go through the motor and build it up. I am excited to get this done

-Simon

[evandael]

better paint that block black if you want to try to pull a fast one on the BAR.

[Mr.SWISS]

lol

[2mAn]

m52b28 by 2mAn

One pic Ive snapped so far. Going again on thursday and putting in a full day. Lets see how much I can get done

[2mAn]

Took the motor to the machine shop today, also snapped a few pics

Is this intake port stock? It looks like its been cleaned up a little bit (sorry for the shitty pic, my camera is old. Really need to get a new one

intakeport by 2mAn

Still waiting to hear back from them about the motor. Head is getting pressure tested and surfaced. Block is getting a hone. I will do most of the assembly, probably

[Vivek]

What's your displacement with that crank?

[2mAn]

What's your displacement with that crank?

2977cc or basically 3.0L

[Wanganstyle]

If you want to bar it and run the OBD2 manifolds then why run obd1 brains?
if goal is obd1 bar status then run the cast iron obd1 M50 iron manifolds; the california bar will notice that all the Air pump injection items are missing unless you can have them deleted to be invisible and are lucky they dont notice.
Also the pinktop injectors may be noticed-

I love playing games with the bar; we have found ways to get Euro/Japan spec engines to pass and get the sticker :)



the Air pump system is harmless and does not do anything but pump additional oxygen into the cats when warming up.
you could easily run it OBD2 with S52 full electronics as you are building a lighter but smaller bore/displacement s52 - quicker response (faster processor) also.

are you going to run M54 pistons? or try to keep the M52b28 pistons designed for a 84mm stroke with the longer stroke 89.6mm stroke S52 crank?

I've been wanting to do something like your hybrid alloy block engine for the race car; the iron 24v is quite front heavy and strategy shifts from cornering battle to drag racing.

Did you source the longmotor from a Z3 2.8?

[GunMetalGrey]

I want your block...

[2mAn]

So I finally got my new C101 plug and pins from Turner Motorsport and arranged it all in my work area. Its simply an unfinished room in our basement. As usual, most people use it as a storage area and I use it as my workshop lol
I need to get the proper crimper and then I will really get cracking on this. I have done a ton of research and printed out a few things to help identify all the wires in the X20 plug.

If you want to bar it and run the OBD2 manifolds then why run obd1 brains?
if goal is obd1 bar status then run the cast iron obd1 M50 iron manifolds; the california bar will notice that all the Air pump injection items are missing unless you can have them deleted to be invisible and are lucky they dont notice.
Also the pinktop injectors may be noticed-

I love playing games with the bar; we have found ways to get Euro/Japan spec engines to pass and get the sticker :)

the Air pump system is harmless and does not do anything but pump additional oxygen into the cats when warming up.
you could easily run it OBD2 with S52 full electronics as you are building a lighter but smaller bore/displacement s52 - quicker response (faster processor) also.

are you going to run M54 pistons? or try to keep the M52b28 pistons designed for a 84mm stroke with the longer stroke 89.6mm stroke S52 crank?

I've been wanting to do something like your hybrid alloy block engine for the race car; the iron 24v is quite front heavy and strategy shifts from cornering battle to drag racing.

Did you source the longmotor from a Z3 2.8?

Not sure how I missed your post.

Main reason for OBD1 is less emission stuff to deal with swapping over. The only obvious OBD2 part I am using is the exhaust manifolds. Still havent figured out what I want to do about the air pump, my car is an 84 so I already have to wire up a CEL, really dont want to swap everything to make it OBD2 legal.

Mostly using what I have, I understand the OBD2 computer is better but it adds more shit to deal with that I would rather not.

I have been on the fence whether or not I want to run the S52 crank because I dont want to buy new pistons and am tempted to just leave the motor a 2.8. I have heard different #s as to what the compression ratio will be with the stock m52b28 pistons and most people say its over 11:1 and Im a little worried that it might be too much for 91 octane.

The motor is from a 97-98 Z3 as those were the only ones that came to the US with the aluminum block. My racing buddy says they never seem to make as much power as the iron block, but Im not building a race car, I am building a street car that will see occasional track days.


oh and GunMetalGrey, Im sure you can find some Z3s in the yard now, they are already 15 years old!!

[Mr.SWISS]

Interesting to see how a stroked AL block handles high RPM harmonics...

Better keep that dual mass on it.

[2mAn]

thats one of my worries, Ive been tempted to just leave it a 2.8

[2mAn]

Went by the machine shop today. They couldn't get the crankshaft bolt off because they didn't have a badass impact, so I took one to them. problem solved.

Next was the whole issue of my pistons. I requested a rehone, and the machinist recommended getting new pistons because he wanted to make sure there would be no blowby. As much I don't want to buy the new pistons, new factory pistons actually cost more than most aftermarket pistons and I am concerned about the engine because of its history. It came from a racecar on the eastcoast and though we aren't 100% sure, this motor was pulled because it was blowing smoke. We did notice on the cylinder walls that one side of each bore (the same side on every bore) didn't have the hone marks anymore. I bitched and moaned but eventually I called Turner Motorsports (TMS) and they have some Wiseco M52 pistons in stock. $150 each... I HATE doing things twice so I will probably break down and get the pistons (and all new bearings) to ensure its done right. Motor should be all reassembled by the time I get back from my vacation.

With that bitching aside, my cylinder head was done so I picked it up. Pressure tested and straightened and cleaned for a little more than a benjamin.





I also had a lengthy conversation with Jason at TMS about the pistons, but we also talked about my setup in general. He also suggested avoiding the s52 crank unless I was going to pay the machine shop extra to make sure there wouldn't be any problems with valve-piston clearance. I decided I am keeping this thing 2.8, dont want to stress the Al block. S52 crank for sale BTW :)

[Link]

This is great.

[2mAn]

small update. Ordered Wiseco Pistons as they were basically the only readily available piston in the first overbore size. Also was going to order new factory bearings, but decided to get the coated ones from Metric Mechanic. Im leaving for Europe for two weeks today so hopefully the machine shop will have my bottom end done by the time I get back. Im itching to drive my car, but I know its still a ways out. *sigh* It will be totally worth it when Im done though, that is a fact