S38/M88 Flavors?

Post by **tsmall07** » Jan 03, 2011 5:05 PM

I've been reading about M5s for a little while now and I've seen several different variations on the S38 mentioned. I can't find 1 place where they're all explained.

Seems to me that:
S38B35 = US e28 M5
S38B35 = US e34 M5
M88 __ = Euro e28 M5

Can anyone fill me in on what I'm missing and maybe what is distinctive about that particular model?

Brent in NZ Hartge 535i · Post by **Brent in NZ Hartge 535i** » Jan 03, 2011 5:14 PM

Seems to me that:
S38B35 = US e28 M5 3.5L 256hp low compression engine 9;1cr
S38B36 = US e34 M5 3.6L 315hp
duplex cam chain set up 10.5:1 cr
M88 __ = Euro e28 M5 3.5L 286HP high compression (single row cam chain setup )10.5:1 cr

rcbmw · Post by **rcbmw** » Jan 03, 2011 6:16 PM

M88 Engine Designations:
M88 Kugelfischer - E26 M1: 5991
M88/1 Kugelfischer - E26 M1: Procar Group 4
M88/2 Kugelfischer - E26 M1: Procar Group 5
M88/3 Bosch DME Motronic - E28 M5: DC91, DC92, DC98, E24: 5531, 5511, 5532 E23 745i (South Africa): 6918

S38 Engine Designations:
S38-B35 Bosch DME Motronic - E28 M5: DC93, E24 M6/ M635CSi (Japan): 5514, 5519,
S38-B36 Bosch DME M1.2 - E34 M5: HD91, HD92, HD93, HD98
S38-B38 Bosch DME M3.3 - E34 M5: HC91, HJ91, HC92

Best,
RCBMW

Philo · Post by **Philo** » Jan 03, 2011 8:43 PM

RCB.... where's the s38 b35 US motronic engine ? Maybe you didn't list it because others did...

Just checking

rcbmw · Post by **rcbmw** » Jan 03, 2011 8:51 PM

The S38-B35 is listed.

Best,
RCBMW

Philo · Post by **Philo** » Jan 03, 2011 10:31 PM

Thanks for the clarification...

So the M5s/M6s shipped to the US had Motronic L-Jetronic injection ? I didn't know that. I thought we had M1.1

Post by **mooseheadm5** » Jan 03, 2011 10:41 PM

ML1.0 Motorsport, IIRC.

Mab1957 · Post by **Mab1957** » Jan 05, 2011 10:01 PM

59hp bump from b35 to b36 in the NA S38? RCB, where and what is the best comparative literature? Is the b36 a straightforward swap into the e28?

Are the designs so different - bore, stroke, piston, head, tcb? Big bump in compression per NZ Brent. What's the hp for the b38?

Post by **mooseheadm5** » Jan 05, 2011 10:15 PM

The increase in power comes mostly from higher compression, fatter cams, and longer stroke. Other gains come from a different intake plenum, updated fuel injection, and better headers.

The motor is pretty much a drop in like the M30B35 is for M30 cars- a different bracket is required for the passenger side motor mount and the exhaust requires modification, or you can use the S38B35 exhaust and take a tiny hit.

The B38 is 340hp.

Mab1957 · Post by **Mab1957** » Jan 06, 2011 8:35 PM

340-256=84hp bump to the b38 Wow! 56hp/cylinder - that's damn good! Where's the list of the interchangeable components that boost the compression/hp of the s38b35 during a rebuild? Is there a cost/benefit opinion out there for those components?

Thinking of that recent thread on E of Mississippi builders:

Leave the short block alone and build the head/fuel delivery = some pickup in hp and longevity. Do a complete rebuild and one would ask; Why stay at 256, can't it be built to the later high hp specs?

Post by **mooseheadm5** » Jan 06, 2011 11:35 PM

The crank, rods, and pistons would have to come from a B38. The B38 also has different cams, cam timing, and even more advanced injection. If you want more power, contact Paul Burke. You can't get to those power levels alone, you need a pro. He makes custom pistons and built one very infamous turbo (Lucifer's Hammer) B38 that put out silly amounts of power.

Matt · Post by **Matt** » Jan 07, 2011 12:27 AM

IMO Gary Beck's S38B35 should be the new "formula" for E28 M5 builds.. i.e. anyone that plans on doing anything with the motor outta just do what he did. Save money by leavin the ports/head and valve sizes alone. It's all factory parts except the standalone management and the hi-comp pistons..

Post by **mooseheadm5** » Jan 07, 2011 12:37 AM

Matt wrote:IMO Gary Beck's S38B35 should be the new "formula" for E28 M5 builds.. i.e. anyone that plans on doing anything with the motor outta just do what he did. Save money by leavin the ports/head and valve sizes alone. It's all factory parts except the standalone management and the hi-comp pistons..

I agree with your point, but the facts are a bit off:

This engine has CP pistons and rings that are 11:1 (approx)
The exhaust side of the head was cleaned up. (ported)
The cams are from a S38 B36 M5 engine (E34) and are at factory settings. No retard or advance.
Stock rods, crank and valves.
Euro headers.
Miller MAF and tunable WAR chip.
UUC exhaust and VSR1 Cats.
Stock ignition, injectors and FPR.

So aftermarket exhaust (though we know that it has little effect on power,) ported exhaust, and a Miller MAF +WAR, which is easier and cheaper than standalone.

Da_Hose · Post by **Da_Hose** » Jan 07, 2011 1:53 AM

Now that looks mighty impressive, Moose.

So are we saying that just the pistons with headers and MAF add up to the same 340 or so HP?

It's awesome if you can build a completely stock looking engine (with stock ignition and EFI system) and just throw in the 11:1 pistons with cam. You could choose not to use the euro header and have a stealth build that might be a couple HP down, but still quite a go-getter.

Jose

Post by **mooseheadm5** » Jan 07, 2011 9:29 AM

You are forgetting the cams and port work.

Mab1957 · Post by **Mab1957** » Jan 07, 2011 7:40 PM

mooseheadm5 wrote:The crank, rods, and pistons would have to come from a B38. The B38 also has different cams, cam timing, and even more advanced injection. If you want more power, contact Paul Burke. You can't get to those power levels alone, you need a pro. He makes custom pistons and built one very infamous turbo (Lucifer's Hammer) B38 that put out silly amounts of power.

I like silly amounts of power. Will keep researching and Paul is on the contact list.

Post by **mooseheadm5** » Jan 07, 2011 9:27 PM

I received a correction about LH, it is actually a built S38B35 block, but from what I can tell it runs the coil on plug valve cover of the B38 (which is the reason I made the mistake.)

It is a fantastic marvel of engine building. If I owned that motor I would lose my license in minutes.

Mab1957 · Post by **Mab1957** » Jan 20, 2011 4:54 PM

How is the S38 engine in the E34 M5 different from the version used in the E28 M5?
The early E34 M5 uses an evolution of the 24-valve inline-six found in the E28 M5 and E24 M635CSi/M6. Despite its official designation of S38 B36, this BMW Motorsport powerplant technically remains a 3.5-liter, with a bore of 93.4mm (same as the previous engine) and a stroke of 86mm (up 2mm on the early S38) for a total capacity of 3535cc (up from 3453cc). The added stroke is due to a new forged steel crankshaft, though the camshafts were also changed. Compression is up slightly (10:1 versus 9.8:1). Further enhancements include:
-An electronically-controlled butterfly valve in the inlet manifold to provide better low-rpm and mid-range power
-Bosch Motronic fuel injection for precise metering of the air/fuel mixture
-Improved flywheel
-Equal length stainless steel headers
-Three way ceramic catalysts (similar to those used on the M70 V12 engine)

The S38 B36 is rated at 315 hp (DIN) or 310 hp (SAE) at 6,900 rpm and 266 lb/ft of torque at 4,750 rpm. Like the earlier S38 B35, it carries the "BMW M Power" inscription on its cam cover but the design of almost every component is different. Also, unlike the engine used in the E28 M5, the S38 B36 engine in the E34 M5 was created to meet all worldwide emission standards from the start. It therefore was equipped with a catalyst as standard equipment in almost all markets, though a special non-catalyst version was produced for South Africa, the Middle East and a few other regions where unleaded fuel was not yet mandatory.

How is the 3.8-liter M5 engine (S38 B38) different from the 3.6-liter version (S38 B36)?
The final evolution of the S38 powerplant, the S38 B38, was introduced in later versions of the European-spec E34 M5. In this application, the bore was increased (to 94.6mm) and the stroke lengthened (to 90mm), raising the displacement to 3,795cc. Though the added capacity makes the S38 B38 the largest six-cylinder production BMW engine of the modern era, it represents only a portion of the major revisions developed by BMW Motorsport at this time. Others include:
-Larger intake and exhaust valves
-Lighter pistons
-Shorter connecting rods
-Increased compression to 10.5:1
-Bosch Motronic 3.3 engine management system
-Distributorless ignition with six coils
-Redesigned intake and exhaust manifolds
-Revised throttle butterfly linked to Motronic engine control
-Dual-mass flywheel with harmonic balancer
-Metal catalysts for reduced backpressure and better heat conduction

The S38 B38 is normally rated at 340 hp (ECE) or 347 hp (DIN) at 6,900 rpm and 295 lb/ft of torque at 4,750 rpm. However, a cleaner version was developed for Austria and Switzerland, rated at 334 hp (ECE) and later 327 hp (ECE). The S38 B38 can be identified by its grey (instead of black) cam cover surround.

From http://www.bmwmregistry.com/model_faq.php?id=12

Brent in NZ Hartge 535i · Post by **Brent in NZ Hartge 535i** » Jan 20, 2011 7:37 PM

i changed my std m88 crank to a bigger std crank from a e34 m30 535i engine . that strokes it with std m88 conceting rods with customs pistons on top bored out to 95mm makes it a 3.65L engine now

winfred · Post by **winfred** » Jan 20, 2011 9:42 PM

i am planning on running my m88/3 on motronic 3.3 from a M50b25 with coil packs, knock sensors and maybe a V8 maf, mark d'sylva is on for doing a remote chip tune, all i need to do is get my e30 blower project wrapped up and start building the new shark from the rusty turd parts car. should be amusing as i have the compression, lumpyier euro cams and headers, maybe toss in one of those spiffy carbon plenums and ill crack 300 to the ground with all bmw parts

Nicke28 · Post by **Nicke28** » Nov 24, 2011 12:50 AM

Bump'n an old thread.

What are the differences or similarities in heads between the B35, B36 & B38's?

Post by **mooseheadm5** » Nov 24, 2011 1:48 AM

The heads are very similar. The intermediate housing (cam housing) is the same for all S38s. The lower part of the head with the chambers is different for each. I believe that the ports are different sizes in each head (largest is B38, smallest is B35) and I know there are other small differences, like a sensor fitting in the front of the B36 and B38 heads, etc. but the basic design is the same for all (since they have to bolt to essentially the same block on the bottom and intermediate housing on top.)

Nicke28 · Post by **Nicke28** » Nov 24, 2011 11:16 AM

Pretty much what I figured. Just wondering because I don't ever recall hearing anyone putting a B36/B38 head on a B35/M88 block or the other way around. I guess all 3 are so similar that there is no need to make reference to such a build.

Post by **mooseheadm5** » Nov 24, 2011 12:55 PM

You usually don't find a B36 or B38 head without the rest of the motor, and much of the gains from the B36 and B38 is from the bottom end so it makes more sense to swap the whole thing.

M5BB · Post by **M5BB** » Nov 30, 2011 10:35 AM

Matt wrote:IMO Gary Beck's S38B35 should be the new "formula" for E28 M5 builds.. i.e. anyone that plans on doing anything with the motor outta just do what he did. Save money by leaving the ports/head and valve sizes alone. It's all factory parts except the standalone management and the hi-comp pistons..

Gee Matt thanks for the compliment.

I went to Ofest this year since it was in Birmingham AL just a 2 hour drive.
I was brave and did a one day DE at Barber Motorsports track.
Since track time is how this engine rebuild got started (burned piston) I was pretty hesitant to go out.
After a few laps and watching the AFR gauge my confidence rose. The car ran flawlessly and by the end of the day I was doing some pretty good laps. No one was passing me. LOL
Of course my ride in the McLaren race car was the highlight of the race track time.
In the end though the M5 is just to nice to have a boo boo at the track and make a mess of it. Need a dedicated track car.
Gary

Philo · Post by **Philo** » Nov 30, 2011 6:01 PM

That's one nice track car.. Very Brave Gary !

Matt · Post by **Matt** » Nov 30, 2011 11:10 PM

Gary,

I came to the same conclusion about not wanting to wad up the M5.

Ironically, a few years after I retired my M5 from track duty, some asshole rear-ended it. I still havent' found a body shop that is excited about fixing it.

So i have all the BMW parts to fix it sitting in my garage, but it remains, broken

I definitely recommend getting an E30 track rat. Too cheap, too fun.

M5BB · Post by **M5BB** » Nov 30, 2011 11:42 PM

Philo wrote:That's one nice track car.. Very Brave Gary !

Or stupid..........

One thing about the Barber track is that it is not too fast.
Not real long straights and the guard rails and barriers are pretty far off the pavement so spinning out would not necessarily total your car. Of course hitting another car could be a problem but I'm in a C group of mostly amateurs so we are not that close together thank heaven.

Matt, I sure hope you can get it fixed. Maybe some shop will be slow in the winter in your area and want some work.

1st 5er · Post by **1st 5er** » Dec 01, 2011 11:34 PM

Good informative thread.
Not sure how I missed it.

Yeah Gary, I think yours is the new standard.

MyE28.com

MyE28.com

S38/M88 Flavors?

S38/M88 Flavors?