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Read the WELCOME ALL BMWFANATICS post.
E28-M5 Engine and Suspension mods
- Thread starter Peter@AEW
- Start date
thats not going to control the spring very well :roflol:
skank
New member
Fordkoppie said:
Aaagh. I can't resist anymore. This comparison has been bothering me for ages because it's bollocks. While I agree the S38 is great the M88 is right up there. BMW went bigger on the bore and stroke because the great big fat E34 wouldn't work with a high revving M88. 1750kg E34 M5 vs. 1450kg M635CSi. The timing chain went to double for reliability as customer were not following maintenance intervals, it puts more strain on the valve train and causes inertia issues.
The correct comparison is:
Forged S38 crank VS Wrong M88 crank is forged
Mahle forged pistons on S38 VS Wrong Mahle forged pistons on M88
Duplex S38 chain VS single M88 chain. Correct debatable improvement.
Bigger S38 valves and ports VS m88 Wrong they are both 37/32mm
S38 has higher valve spring rates Wrong BMW did a recall on all M88 to fit dual springs
S38 = more duration + lift than M88 Wrong Both are 264 duration and 10mm lift
Superior crank to harmonic balancer interface on s38. Maybe
skank
New member
In all honesty, I was not sure on the valves. I have obviously had M88 and M1 valves in my hand, but not B36 valves.
I can only shrug as REALOEM and BMWFANS both declare B36 valves as 37/32.
http://bmwfans.info/parts-catalog/E...engine/valve_timing_gear_cam_shaft/#1309343_3
http://www.realoem.com/bmw/enUS/showparts?id=HD93-USA-07-1990-E34-BMW-M5_36&diagId=11_1266
Even VAC lists the same for the B36. I had however had 38mm inlet in the back of my head so will acquiesce on the valves.
The rest however is correct.
I can only shrug as REALOEM and BMWFANS both declare B36 valves as 37/32.
http://bmwfans.info/parts-catalog/E...engine/valve_timing_gear_cam_shaft/#1309343_3
http://www.realoem.com/bmw/enUS/showparts?id=HD93-USA-07-1990-E34-BMW-M5_36&diagId=11_1266
Even VAC lists the same for the B36. I had however had 38mm inlet in the back of my head so will acquiesce on the valves.
The rest however is correct.
Fordkoppie
///Member
skank said:
Actually you are wrong on the valves.
The S38 does have 1mm bigger valves.
And you are also wrong on the cams.....
S38 has 264 deg duration cams whereas the M88/3 (as found in the e23/e28) has 256 deg duration cams. The american junk s38b35 had 248 deg cams, but luckily we never got that engine here
The crank is debatable. The M88 in the M1 might have a forged crank, but the ones found in the e23 and the e28 does not
There is a reason why the M88's power starts dropping off after 6500 rpm + a 6900 rpm rev limiter whereas the s38's only start dropping off after 6800 rpm mated to a 7300 rpm rev limiter.
Out of interest - did you know that the M88/1 as found in the M1 also had a duplex timing chain
They really went cheap when they started fitting these revised M88/3 engines to the normal production cars
Speculating over this is actually a little pointless, because we both can only type here what we have read on the internet previously. And as we both know, the internet can be wrong in many instances.
I would only believe any of those numbers after the cams were actually ran through a cam profile recorder.
PS - I have personally seen more than 1 broken M88 crank :mmm:
Time for an update.
The plenum was stripped off its red powder coating substrate which entailed a fair amount of work to achieve.
The wrinkle black paint is interesting in its application.
New rubber.
The cone filter is being used out of necessity as the filter airbox did not come with the car.
Owner is looking for one btw.
Still waiting for new radiator and a few small bobs and bits from the agents.
The plenum was stripped off its red powder coating substrate which entailed a fair amount of work to achieve.
The wrinkle black paint is interesting in its application.
New rubber.
The cone filter is being used out of necessity as the filter airbox did not come with the car.
Owner is looking for one btw.
Still waiting for new radiator and a few small bobs and bits from the agents.
Today I had Gert pop over to help me start the car.....(read that as today Gert came over to start the car as the wiring was a mess).
He worked on it from 10:00 untill 19:00 non stop tracing the cars wiring loom where it had been butchered removed.
I cannot begin to tell you what a frustrating day it has been as the car had an aftermarket ecu system on it and the way it had been worked on was a maze of cuts and twists on the loom.
To cut a long story short the car is running and the correct wiring loom is in place.
The owner brought in a Miller Performance MAF and WAR chip which was correctly installed by Gert and the software written on the ECU.
Gert thank you for the effort and perseverance in resolving this tiny,minor,insignificant wiring issue which had me pulling my hair.
A few pics of Yoda's work.
btw remember how the engine was all assembled......
Yep that is the ECU open and being measured
A job well done Gert!
He worked on it from 10:00 untill 19:00 non stop tracing the cars wiring loom where it had been butchered removed.
I cannot begin to tell you what a frustrating day it has been as the car had an aftermarket ecu system on it and the way it had been worked on was a maze of cuts and twists on the loom.
To cut a long story short the car is running and the correct wiring loom is in place.
The owner brought in a Miller Performance MAF and WAR chip which was correctly installed by Gert and the software written on the ECU.
Gert thank you for the effort and perseverance in resolving this tiny,minor,insignificant wiring issue
which had me pulling my hair.A few pics of Yoda's work.
btw remember how the engine was all assembled......
Yep that is the ECU open and being measured
A job well done Gert!
A new ECU harness was sourced and repaired look at page 2...Gert also fixed that one.
The problem we faced was the main car harness which had been "modified" by whoever fitted the aftermarket ecu of unknown make and origin.
We still need to source a few plugs and trace the wires to make the rev counter work as well as the OBD.
The problem we faced was the main car harness which had been "modified" by whoever fitted the aftermarket ecu of unknown make and origin.
We still need to source a few plugs and trace the wires to make the rev counter work as well as the OBD.
