m20 2.7 stroker help

[Gplayer]

I'm new to the forum and new to BMW's. I've got an 89 four door with an M20 stroker in it. Turbo diesel crank, shrick cam, etc.

The problem is, I traded for this car, and was told the AFM was bad, and so it wouldn't drive well. When I got it, it was worse than "wouldn't drive very well" Throttle response is non existent, it takes a year for the car to rev after you blip the throttle, and it's running stupidly rich. Like, burn your eyes at idle rich. I got another AFM, fixed a few suspected vacuum leaks, and it didn't change a thing. So then I went into the ECU. I was told there was a Turner/Conforti ship in it, but I pulled it out and there is an aftermarket chip, but it just has a paper label saying "87-92 BMW 325/525 0 261 200 173" Which I take to mean as it's just a basic chip.

So currently, I'm guessing the PO lied to me and never actually drove this car, and that the tune was never done for the stroker setup.

How do I go about identifying this chip and where do I start looking to fix this thing?

[superj]

maybe put a stock chip in it for now? it sounds like an ebay chip is in it right now. it should still run with that chip but who knows what else is not stock right now

[Gplayer]

I don't have the stock chip. The car runs on the current chip, just runs like shit. It would have to run worse on a stock chip, the fuel tables would be so far off for the cam

[superj]

not sure. it sounds like the afm is not hooked up but you already swapped the bad one so unless the replacement is also no good, you are stuck tracing and testing everything out. (which sucks)

[95BMWIC]

If you truly believe its the chip then reach out to Turner, tell them your setup and order another one.

I would also get some more information from the Previous Owner (PO) so you know exactly what was done (you may already have this info).

Then I would check out this forum for Stroker info:http://www.e30tech.com/forum/forumdisplay.php?f=43

[Gplayer]

I swapped a used one for a used one, so I haven't ruled the AFM out yet, but I also haven't gotten around to testing it. I did notice it has a plug in place of the IAT, what difference would that make? Does that mean I've got a completely different year AFM?

[Gplayer]

If you truly believe its the chip then reach out to Turner, tell them your setup and order another one.

I would also get some more information from the Previous Owner (PO) so you know exactly what was done (you may already have this info).

Then I would check out this forum for Stroker info:http://www.e30tech.com/forum/forumdisplay.php?f=43

PO gave me a list of the setup as he was told, but I don't know exactly what to believe. I called Turner a couple times and couldn't get in touch with anybody, so I reached out on a local forum and was put in touch with a tuner named Mark D'Sylva (EAT?) who said he would read it for either $15 or free if I bought a chip from him after he read it.

Hesitant to do that though because he routes everything through a shipper in Ohio. Found a few people vouching for him with a quick google search but not enough to make me super confident.

Also, any ideas how I would go about verifying that it's actually stroked without yanking the motor apart?

[nick325xit 5spd]

Mark D’Sylva is a good guy and sharp. He routes through a shipper because of the cost of transshipment to Canada. I have a couple of his (standard) E30 tunes, as well as an S50B32 EWS delete+tune with from him.

[superj]

yeah, he is a well known guy for chips. you are safe with him

I don't know enough about stroking m20s to help on your question. I never tried it but I was in the same boat as you, a few years back in a wrangler. I bought it and went to do some work on it and parts weren't right. it had a newer block but older head. I posted some pictures on jeepstrokers and the guys pointed out some things which told them it was stroked and could be from a 4.5 up to a 5.0 but without tearing the head off, that's as much as could be told. I just told people it was a 4.5 since it was the smallest stroker build you could do on that block

[hotdish]

If you car is running ridiculously rich, it might be more than just the tune. I would check to make sure the fuel injectors aren't stuck open and you don't have a clogged FPR or something like that. Your fuel injectors might also be mismatched to the tune, o2 sensor could be bad, TPS could be bad, etc.

[Gplayer]

Okay, so I'll start with mailing Mark the chip to see what it says.

It's got 19lb injectors supposedly. I need to verify that.

I've got some experience with tuning, obd1 specifically, I built an old school fuel injected small block chevy that had ported heads and a bigger cam, and this is exactly how it acted on a basically stock tune. Which is why I'm leaning towards the tune, I know it's anecdotal, but it makes sense to me.

Also, one other question is the AFM I swapped out doesn't seem to have an IAT, it's got a rubber plug where the old one has the thermoresister. Any ideas what that means? And would that keep me from using it going forward? The old one is definitely dead. It had water inside of it.

[superj]

I think the I model afms didn;t have that side temp sensor on them, the newer I model afm. I don't remember my 89 having that sensor on it, like my eta afms have

[95BMWIC]

Also, any ideas how I would go about verifying that it's actually stroked without yanking the motor apart?

Not really. I'm working on this very project right now (been at it 2 years - just need to order pistons - bought a Porsche got side tracked) You can't tell from the outside - you'll have an 885 head and the block (e or i) looks the same. You could verify the cam is a Shrick by popping the valve cover.

The basic stroker has a crank (most likely) will be from an "e" (or turbo diesel as you state - but from my limited understanding those are hard to find), the pistons will be custom or from an "i" engine and the rods will be custom (if "i" pistons) or from an "i" with custom piston heads (or shaved). The process isn't hard, but the forum is filled with bad stroker builds - you have to have a level of knowledge higher then a general mechanic and building a motor (that runs properly) requires experience and skill.

Lot of valuable info here: http://www.strictlyeta.net/technical/328i_1.html

Again - There are a few on this forum that have the knowledge you are seeking although I don't believe they are on this forum all the time. I would read the e30tech threads (not an endorsement) just that they get into the stoker conversations - particularly read "the M20Stroker FAQ thread" - its legendary.

[hotdish]

Disconnecting one motor mount, hoisting the engine up a bit, and pulling the oil pan would probably be the easiest way to verify which crank it has.

You also might be able to pull a spark plug and get a tiny camera in there to see if it has eta, i, super eta, or custom pistons.

[superj]

those little boroscope cameras they sell on facebook ads would be great for you right now. I bought one for 19.99 last year and it is unbelievably useful for seeing in and around things instead of taking them apart. maybe see if the local autoparts place has a small boroscope you could use?

[Gplayer]

Not really. I'm working on this very project right now (been at it 2 years - just need to order pistons - bought a Porsche got side tracked) You can't tell from the outside - you'll have an 885 head and the block (e or i) looks the same. You could verify the cam is a Shrick by popping the valve cover.

The basic stroker has a crank (most likely) will be from an "e" (or turbo diesel as you state - but from my limited understanding those are hard to find), the pistons will be custom or from an "i" engine and the rods will be custom (if "i" pistons) or from an "i" with custom piston heads (or shaved). The process isn't hard, but the forum is filled with bad stroker builds - you have to have a level of knowledge higher then a general mechanic and building a motor (that runs properly) requires experience and skill.

Lot of valuable info here: http://www.strictlyeta.net/technical/328i_1.html

Again - There are a few on this forum that have the knowledge you are seeking although I don't believe they are on this forum all the time. I would read the e30tech threads (not an endorsement) just that they get into the stoker conversations - particularly read "the M20Stroker FAQ thread" - its legendary.

I was reading through the Stroker FAQ earlier. Good info for someone building a stroker, but I couldn't find much to answer my questions specifically. Need to dig through it deeper. I've got a starting place though for when I get around to checking on the pistons, and that's something. Really wish the kid I got this from hadn't lied about anything, everytime I find something he wasn't truthful about, it makes me question everything he told me. All I know for certain now is that it's got a cam and 19lb injectors.

- - - Updated - - -

those little boroscope cameras they sell on facebook ads would be great for you right now. I bought one for 19.99 last year and it is unbelievably useful for seeing in and around things instead of taking them apart. maybe see if the local autoparts place has a small boroscope you could use?

I've got one somewhere, I need to see if it'll actually fit through the plug hole.

- - - Updated - - -

I think the I model afms didn;t have that side temp sensor on them, the newer I model afm. I don't remember my 89 having that sensor on it, like my eta afms have

Does it make a significant difference tuning wise? The computer has to be able to know air temp to calculate air mass right?

[nick325xit 5spd]

A 2.7 will drive OK on a stock chip. That’s within the adaptation range.

[superj]

Does it make a significant difference tuning wise? The computer has to be able to know air temp to calculate air mass right?

I think on the newer I model afm, there is a deal inside the flapper area that the computer gets air temp from, not one on the outside like the older afm. I think I remember that from when I was doing megasquirt on my 89 325i. but, hopefully someone else can come verify because that was probably 10 or 12 years ago and I could easily be remembering wrong

[Gplayer]

A 2.7 will drive OK on a stock chip. That’s within the adaptation range.

Okay, so I should be looking elsewhere to get this thing running okay, the chip is not keeping it from doing that?

[nick325xit 5spd]

Okay, so I should be looking elsewhere to get this thing running okay, the chip is not keeping it from doing that?

Correct. It's not ideal, but it will run perfectly acceptably. You need to fix your other running problems first. Or get the chip, because you will want it either way. Just don't expect it to actually fix your problems.

[Gplayer]

So I got in touch with the kid I got this thing from again and got a more concise list of parts.

524TD crank, 325e rods, pistons, and block.

325is head, plugs, injectors, intake mani, and throttle body, 288 Schrick cam

325is redtop ECU, generic 325i "performance chip".

325i AFM.


What do I need to know about this setup for diagnosing the problem and fixing it?
Anything special as far as which AFM to look for or anything like that?

forgive my ignorance, I'm new to BMW's, I know nothing about them when it comes to interchangeability and specifics and all that.

[actletpone]

Can you be sure there are no other vacuum leaks? Also it sounds like some multimeter test on the throttle position sensor / coolant temp sensor / AFM wouldn't go a miss

[nick325xit 5spd]

Also, an old intake boot may collapse under acceleration. This was the source of a 3000RPM "rev limit" on my friend's halfassed 2.7 that he bought.

[95BMWIC]

So I got in touch with the kid I got this thing from again and got a more concise list of parts.

524TD crank, 325e rods, pistons, and block.

325is head, plugs, injectors, intake mani, and throttle body, 288 Schrick cam

325is redtop ECU, generic 325i "performance chip".

325i AFM.


What do I need to know about this setup for diagnosing the problem and fixing it?
Anything special as far as which AFM to look for or anything like that?

forgive my ignorance, I'm new to BMW's, I know nothing about them when it comes to interchangeability and specifics and all that.

The first thing that pops out to me is you have "e" pistons and running an "i" head. This may be problematic as the "i" head is dome designed for "i" (domed) pistons.
"e" pistons are flat. The "e" head combustion chamber is designed for a flat piston the "i" head is not. Jut installing the flat 325e pistons into a 325i head may cause a mismatch and my guess is a much lower compression ratio. Super "eta" pistons would work - but those pistons were only used for one year (I think 1988 and the BMW was badged as 325 - no "e")

http://www.strictlyeta.net/technical/328i_1.html

Not real sure of what the compression ratio would be.. HOWEVER a quick review of the literature suggest your setup can be fired and tuned..

http://www.e30zone.net/e30zonewiki/i...Building_a_2.7

Reading through the e30tech forum they discuss pistons throughout.. Somewhere in here I read that a Mark D chip would work - maybe reach out to him?
http://e30tech.com/forum/showthread.php?t=48288

R3Vlimited has a few members that are knowledgeable on strokers - Digger, ForcedFirebird and Nando are some active posters that could provide you some help.

[Gplayer]

Well, I checked the AFM and TPS, TPS seems to be okay, It's switching as it should. The AFM is not. It's got a number of rough patches in the carbon strips where the resistance jumps around throughout it's arc. I guess I need to find a known good one and start again.