2nd December 2012, 16:05
M5 Guru (>2000 posts)
Join Date: Jul 2012
Location: Jakarta, Indonesia
1990 E34 M5 Shwarz II
Thanked 99 Times in 91 Posts
Originally Posted by davidoli
I don't believe many owners have completed a build using PPM's kit yet .
This crank doesn't look like one of their's !
Is a 4.1 or 4.2 litre stroker is going too far ?
A standard 3.6 has a piston speed of 20.16 metres per second at 7,200rpm, 86mm stroke
3.8 litre is 21.6 at 7,200 (is the rpm limit on the 38B38 the same or lower than the B36 ?), 90mm stroke
This particular 4.1L is 23 m/s at 7,200rpm, 96mm stroke.
4.2 litre 23.5 metres per second at 7,200 , 98mm stroke ???
If you took a 4.2L to 8,000 that would be 26.1 metres per second (assuming a race engine build with a higher rpm limit), formula 1 engines are doing about 27m/s. A race 4.2L would have a life of only a few thousand km at those piston speeds ?
A good discussion here
Engine & fuel engineering - maximum piston speed?
Tony, Aussie expat in Jakarta Indonesia
1990 E34 M5 S38B36 GA25324 Schwarz II, 57,000kms, Tropical version, full Nappa leather interior, Superchip , staggered TS 235/45 ZR17 , 255/40 ZR17 Toyo T1R Mods + work planned : exhaust system (packing removed from centre + rear mufflers) Restoration items : Reinstall the SLS, interior tidy up, bodywork : repair small dents and re-coat in the original color
1991 E34 M5 S38B36 GA25388 Schwarz II. Non running 1/2 share parts car with BlueBiTurbo (Taffy)
1995 E34 530i 5 speed Daytona Violet 161,000kms , M-Par staggered set up, M-Tech steering wheel mods planned: ENGINE: M60B40 (purchased), chip EXHAUST : 110mm big bore front Y pipe (done), centre muffler gutted (no packing), used M5 rear muffler (done) BRAKES: slotted + drilled discs TYRES: 245/40 ZR18 , 265/35 ZR18 Toyo T1R - my daily driver and a car that I can play with and modify. Long term dream - full E39 M5 drivetrain
Last edited by AseanAero; 2nd December 2012 at 16:19.