Running M44 build!
« previous next »
Pages: [1] 2 3 ... 5   Go Down

Author Topic: Running M44 build!  (Read 33566 times)

benz-tech

  • Full Member
  • ***
  • Thank You
  • -Receive: 15
  • Posts: 242
    • View Profile
Running M44 build!
« on: November 14, 2013, 11:03:33 PM »
I have acquired an entire M44 including ECU EWS, key, Gt250 trans etc for install into my 91 318i. Not one to leave well enough alone, I am building the M44 w/ US S50 pistons to achieve approx.  11:1 compression and 1950 or so CC's.
I need a bit of help calculating compression ratio before I mill the pistons to fit.
I have 4 US S50 pistons awaiting the end mill to remove excess material off the deck. the numbers are below and I could use some help in figuring out the CR.
bore: 86mm
stroke: 83.5mm
HG thickness crushed and verified 1.6mm
dish of piston is 64mm X .8mm depth matching the .15 + deck of the stock M44 piston. (after removing approx. 2.5mm of the squish area of the piston)
I don't know the exact combustion chamber volume and the head is at the shop so I cant verify ATM.
Anyone better at math than I? or send me to a site with

edit: list of mods for frankenmotor.
M44 block, rods, crank, harness, dme, ews2, chip, cam sprockets, maf, coolant temp sensor, upper front timing cover, front cover and all timing components, beehive valve springs and retainers. All accessories inclu a/c and p/s
M42 late cylinder head, 6mm valves, mild port work.
E30 M42 oil pans, intake manifolds and valve cover, Temp sensor for guage, Cams with reground intake
S50pistons US (with approx 2.4mm milled off the deck- not a verified number),
S52 33mm lifters and trays.
M20 lwf -12.5lbs (still too heavy) and clutch

There you have it- arguably 6 different engines in one,

« Last Edit: December 08, 2015, 11:38:15 PM by benz-tech »
Logged
Pi is apparently the multiplier for your engine swap budget as well.

benz-tech

  • Full Member
  • ***
  • Thank You
  • -Receive: 15
  • Posts: 242
    • View Profile
Re: M44 build
« Reply #1 on: November 14, 2013, 11:45:23 PM »
So please verify my math - assuming a 35cc combustion chamber
485 cylinder volume
9.2 volume of HG
33. Chamber
527cc.  total

volume at TDC 42 total –assuming a perfect flat top, 12.4:1
BUT
dish of the piston is 64mm x 59mmX 1.1mm
Dish: 4.0
531 /  46 =
approx. 11.5:1 static compression ratio.
I need to add 1cc to get down to around 11.3
Edited to reflect updated numbers.
« Last Edit: February 15, 2014, 09:30:54 PM by benz-tech »
Logged
Pi is apparently the multiplier for your engine swap budget as well.

benz-tech

  • Full Member
  • ***
  • Thank You
  • -Receive: 15
  • Posts: 242
    • View Profile
Re: M44 build
« Reply #2 on: December 26, 2013, 11:16:00 PM »
A bit of an update: The M44 head was cracked and needed every exhaust valve and every guide due to the poor cam/rocker design. So I found a late M42 head, and, using the M44 front upper timing cover, sensor and the M44 cam gears, it looks like I can run the M42 head. The S50 pistons have been milled to the proper deck height and are on their way with the block to get bored. Found a M20 flywheel and got it down to 17lbs before the belt on my buddy's lathe started slip. With the lighter M44 crank, pistons and rods I might just leave it there and not go any lighter, but I am tempted to.
I'll get pics up when I have something worth showing.
Logged
Pi is apparently the multiplier for your engine swap budget as well.

wazzu70

  • Nasty Nick
  • Hero Member
  • *****
  • Thank You
  • -Receive: 18
  • Posts: 671
    • View Profile
Re: M44 build
« Reply #3 on: December 29, 2013, 11:45:57 AM »
Sounds like an interesting build, excited to see how it turns out!

How much did you end up milling off the piston tops?
Logged
-Nick
91 E30 M42 with VEMS

DesktopDave

  • Administrator
  • Legendary
  • *****
  • Thank You
  • -Receive: 60
  • Posts: 5076
  • Lives in the 80s
    • View Profile
    • The Iconic BMW
Re: M44 build
« Reply #4 on: December 30, 2013, 11:11:42 AM »
Wish I could help - this sounds like a very unorthodox, cheap & clever build. Using an M44 crank is a LOT cheaper than finding & machining the M47 crank.

I'm still trying to figure out how you gained 100cc's with new pistons, but I'm geometrically challenged. Keep us updated!
Logged
'08 Karmesinrot 128i 6MT
'86 Zinnoberrot 635CSi (M30B32/G265/3.46 torsen LSD)

Sold: '97 Montrealblau 318iS, '91 Brilliantrot 318i, '91 Brilliantrot 318iS

wazzu70

  • Nasty Nick
  • Hero Member
  • *****
  • Thank You
  • -Receive: 18
  • Posts: 671
    • View Profile
Re: M44 build
« Reply #5 on: December 30, 2013, 07:31:32 PM »
If I build another 4cyl I will probably go with the M44 crank just because its more torque and MUCH more cost effective. Heck, an M44 crank is probably even easier to come by and cheaper than an M42 crank!

M47 is the way to go, but Im a cheapo so I just use whats available :)
Logged
-Nick
91 E30 M42 with VEMS

benz-tech

  • Full Member
  • ***
  • Thank You
  • -Receive: 15
  • Posts: 242
    • View Profile
Re: M44 build
« Reply #6 on: December 30, 2013, 10:44:19 PM »
I started on the intake ports.
Logged
Pi is apparently the multiplier for your engine swap budget as well.

benz-tech

  • Full Member
  • ***
  • Thank You
  • -Receive: 15
  • Posts: 242
    • View Profile
Re: M44 build
« Reply #7 on: December 30, 2013, 10:49:33 PM »
Quote from: DesktopDave on December 30, 2013, 11:11:42 AM
Wish I could help - this sounds like a very unorthodox, cheap & clever build. Using an M44 crank is a LOT cheaper than finding & machining the M47 crank.

I'm still trying to figure out how you gained 100cc's with new pistons, but I'm geometrically challenged. Keep us updated!
Well 100 ish more CC's. 1940 cc total. I mostly picked the m44 bottom end to be able to use the S50's and get 11+ to one. C/R.
I could use some help picking cams. I'm hoping to find cheap re grinds. It will need to pass Cali smog when it's all said and done so im thinking no bigger than 270 at the most. Not sure of the int/exh split either. When I look at our benz heads, the intake valves are around 5mm larger and the exh valves are around 2mm smaller. I have a feeling BMW didn't get the ratio right. Cams could offset that a bit?
« Last Edit: December 30, 2013, 10:54:07 PM by benz-tech »
Logged
Pi is apparently the multiplier for your engine swap budget as well.

benz-tech

  • Full Member
  • ***
  • Thank You
  • -Receive: 15
  • Posts: 242
    • View Profile
Re: M44 build
« Reply #8 on: December 30, 2013, 11:33:17 PM »
Quote from: wazzu70 on December 29, 2013, 11:45:57 AM
Sounds like an interesting build, excited to see how it turns out!

How much did you end up milling off the piston tops?
About 2.4mm. They are still very much dish shaped. Now that I figured out how to post a pick straight from my phone, many more will come. 
Logged
Pi is apparently the multiplier for your engine swap budget as well.

bmwman91

  • Administrator
  • Legendary
  • *****
  • Thank You
  • -Receive: 33
  • Posts: 2798
    • View Profile
    • http://www.e30tuner.com/
Re: M44 build
« Reply #9 on: December 31, 2013, 12:01:29 PM »
For reference, I am running 272° / 258° cams with 11.4mm / 11.1mm lift on my intake and exhaust, respectively. Valve heads are the stock diameters. Static CR is ~11.5:1 and am using 24# injectors. No issues passing SMOG in the CA Bay Area where regulations are tight. As long as you have a GOOD software tune you should be just fine. That, and a functional cat.
« Last Edit: December 31, 2013, 12:03:36 PM by bmwman91 »
Logged

06/05/2011 - 212,354 miles
Visit HERE for a plethora of 318iS stuff and some other randomness.  Would you say I have a, plethora, of pinatas?

benz-tech

  • Full Member
  • ***
  • Thank You
  • -Receive: 15
  • Posts: 242
    • View Profile
Re: M44 build
« Reply #10 on: December 31, 2013, 11:55:14 PM »
Thanks bmwman. My budget might force just an intake cam but I'd like something like your setup. MM seems to use a 10+ degree difference on their cam grinds, and I'd guess that they have spent some dyno time figuring that out.  any issues with 91 crap gas and that compression ratio? Cams obviously help keep the DCR down and subsequently the combustion temps. At least at lower RPM's.
Logged
Pi is apparently the multiplier for your engine swap budget as well.

bmwman91

  • Administrator
  • Legendary
  • *****
  • Thank You
  • -Receive: 33
  • Posts: 2798
    • View Profile
    • http://www.e30tuner.com/
Re: M44 build
« Reply #11 on: January 01, 2014, 02:46:04 AM »
So far so good on the garbage 91 octane winter blend stuff here.
Logged

06/05/2011 - 212,354 miles
Visit HERE for a plethora of 318iS stuff and some other randomness.  Would you say I have a, plethora, of pinatas?

Warsteiner

  • Hero Member
  • *****
  • Thank You
  • -Receive: 21
  • Posts: 576
    • View Profile
Re: M44 build
« Reply #12 on: January 01, 2014, 12:59:31 PM »
I'm only running 250*/250* combo with 10.4mm lift. Passed NJ inspection with no problem.

benz-tech...Be careful on your cam choice and don't go too big. From the pic of your port, it's pretty hogged out and that alone will drop your low end umpf. Adding an aggressive cam to that will make low end torque really suffer. Have you put the valves back in the head? I would double check to make sure they slide easily. Hard to tell from the pic but since removing all of the valve guide in the port I would check it.

So we all need to get some dyno time in so we can tell what all these mods actually do for us in the real world instead of guessing:-)
Mine is still road tuning and then I'll be ready for the dyno and be happy to share build info as well as tuning info.

Good luck with the build, it looks very promising right now for some good power.

Cheers,
~Ralph

Happy New Year everyone......
Logged

benz-tech

  • Full Member
  • ***
  • Thank You
  • -Receive: 15
  • Posts: 242
    • View Profile
Re: M44 build
« Reply #13 on: January 01, 2014, 04:22:33 PM »
Interesting you should mention valves.  For whatever reason they don't want to go back in. And I pre-drilled the bottom of the guide so there'd be no side-loading. I Had no issues when I did this to a 7mm valve head. I will look into that next week. Do you have some insight jnto this?
Honestly the ports are hardly opened up at all. Maybe 1 mm off the roof and i just smoothed the transissions in the bowl area.
I'm hoping that a dual length manifold, high compression and an extra 175cc's will enhance the low end enough to offset bigger cams
« Last Edit: January 01, 2014, 04:49:48 PM by benz-tech »
Logged
Pi is apparently the multiplier for your engine swap budget as well.

Warsteiner

  • Hero Member
  • *****
  • Thank You
  • -Receive: 21
  • Posts: 576
    • View Profile
Re: M44 build
« Reply #14 on: January 02, 2014, 12:15:49 AM »
It's hard to tell by the pic but it looks really ported but I'll take your word for it. It looks like you burred the valve guide itself not allowing the valve to be reinserted when you removed it from porting. I tend to leave the end of the valve guide in the port because it gives the valve stability and keeping it inline with its trajectory. I only see the valve guide in the port removed on race motors that are going to get rebuilt somewhat frequently and looking for every bit of flow they can get. Don't force the valve back in. Drop one in and see if it gets to the port. If it stops there then you've found your issue.

HTH...

Cheers,
~Ralph
Logged
Pages: [1] 2 3 ... 5   Go Up
« previous next »