Getting torque from M52

[ForcedFirebird]

torque at low rpm is all about
- cubic inches
- compression
- cam timing
- burn efficiency

Yup. Even the poor efficiency of an 885 head on a US bottom end can have gobs of torque ;) Running b25 HP and more ETA torque than from the factory with the "budget strokers" we have been building always puts smiles on racers' faces.

[digger]

885 and poor efficiency? it is one of the better 2V out there so much swirl the 4V heads go crying to their mommy. if everything was the same between M20 and M5x except chamber the M20 would probably be better for torque, purely academic though

[ForcedFirebird]

885 and poor efficiency? it is one of the better 2V out there so much swirl the 4V heads go crying to their mommy. if everything was the same between M20 and M5x except chamber the M20 would probably be better for torque, purely academic though

Was talking about the mating of a US spec eta and 885 head. Sorry, left that out :(

[slammin.e28]

S52 bottom end.

BOOM.

Going to totally rebuild it. New bearings, seals, rings, etc. Gonna run the dingle-berry hone through and clean up the bores, not that there is anything wrong with them. Should be a cool little project. Not going to be done ANYTIME soon, but none the less, should be fun.

Just need to find a good e30 driveshaft to finish putting my M60 car together.....

[Andrew325is]

Ever get this figured out? I have the S52 in the Defender with stock S52 cams, but I also have a set of M52 cams. I've tried searching for dyno graphs of differences between cams, but I haven't had much luck. Most people add a bunch of other mods like the intake manifold so it's difficult to see what differences in the power curve are attributable to the cams only. My S52 is 100% stock with the OBD2 manifold. I've found dyno graphs of 264/256 Schrick cams in an S52 and it looks like the bottom-end isn't affected. So I don't know how much benefit on the low-end can be gained going the other way with short duration cams.

Maybe I will have find a shop nearby with a 4x4 dyno and test both cams. I also don't know enough about engine design as to whether changing the exhaust cam only would be any better, or a good idea at all. I think I'll leave my engine alone though because any mods like the cams will require custom tuning and I don't really want to mess with that.

Here are some other things I've thought of for M52b28 if you or anyone else wants to try to get more torque out of it.

-Try the Defender 2.8i tune. I would think Land Rover/BMW would have tuned the M52 for low-end torque in the Defender, but I don't actually know. It would be interesting to compare dyno graphs of the 2.8i tune and a BMW car tune (e.g. 528i) in the same vehicle. You can get an MS41.0 DME and flash it with WinKFP. The ZB number for the Defender M52 tune is 1438099. (You might be able to use a 3rd party flasher like MS41 Quickflash to flash the MS41.0 tune to an MS41.1 DME, but WinKFP will brick it.)

-Try adding the hemholtz resonator on the intake from the 528i. BMW calls it an intake silencer, and it does muffle sound a little, but it's actual purpose is to increase low-end torque. It provides a reserve of air for the intake.

[slammin.e28]

I ended up parting it out. Rust got the body hard.

I sold the engine to a friend who built the S52 bottom etc and put it in a defender. It was pretty good. I remember he ran a very tiny exhaust to help with the torque. I don't know what happened to the truck. Look up Sarek Autowerke, that's his shop. He got deep into M7x swaps but now he's big into building the new Defenders up. I swear there's some info in posts from a few years ago.

Body got scrapped and I kept the frame for my rotten Series 3 109, which was to be V12'd....but life happened lol.

Sorry I'm not much help. Between kids and work I haven't had time for anything....my next build was going to be a M54B30 into my D2 but that's been backburnered for years now....