M50 Strokers - Camshaft Internal Clearance

[f0xy]

Just wondering if anyone who's been there and done the M50 stroker over the years has run aftermarket camshafts, and if they had issues with fitment/clearance.

I've ran the stroker for around 2 years, similar over here in the UK with the M54 internals, just we don't have the same M3 camshafts to drop in. I run on standalone management with the following spec:

M50 Iron Block
M54 Crank/Pistons/Rods
M52B28 Head (Single VANOS)
M54B30 Inlet Camshaft (240deg/9.7mm)
M52B28 Exhaust Camshaft (228deg/9.0mm)
M20 Flywheel
M50 Inlet + TB
Euro M3 Headers + 2.5" Single Exhaust

VANOS is engaged from 1000rpm>5000rpm (slightly longer than normal, which seemed to bring a bit more mid-high range torque). It made 265hp/260lbft (Crank), and runs very well.

How aggressive have people gone with camshaft profiles with regards to lift on the M54 pistons in this configuration? Considering the pistons sit below the deck @ TDC, is there more space than say an M52B28? Although the M52 pistons have larger valve reliefs...

If anyone has any experience it would be appreciated....

[DesertBMW]

you will not make more power with more aggressive camshafts unless you can raise the compression ratio up.

[Northern]

you will not make more power with more aggressive camshafts unless you can raise the compression ratio up.

Gold :rofl:



Edit: Don't people usually run an M50NV intake cam as the vanos exhaust cam for that sort of setup?

[Pudmunkie]

Wow, great power. I have the exact bottom end sitting around assembled. Might have to throw my shricks in and give it a shot.

Sent from my Nexus 5X using Tapatalk

[f0xy]

you will not make more power with more aggressive camshafts unless you can raise the compression ratio up.

Ok.

Well this motor is going to be a second one, all the bits are on the bench here, with a spare M50 iron block. From what I've read its a given the ratio of the 'usual stokers' are around 10.1:1, if not slightly less.

Without custom pistons, realistically I suppose you're only going to gain a few points of compression by taking a bit from the deck, or running a thinner gasket, which I've seen people have done with the US S50 cams (which are higher lift than I currently run anyway). I think those were calculated at 10.4-10.5:1. Correct me if I'm wrong though.

The engine that is going to potentially get cams will also run Jenvey ITBs, which have come from another motor, we are just going to swap them onto some Jenvey M52 manifolds as a bolt on.

Measuring the clearance isn't an issue - the problem is we don't have the cams yet, and considering they are ground to order, we don't really want to purchase a set that won't clear internally

[nando]

you will not make more power with more aggressive camshafts unless you can raise the compression ratio up.

this is 100% incorrect. While a cam will reach it's best potential with a higher CR (due to the fact that the tighter LSA will result in a lower dynamic CR), it will still increase the breathing of the motor and it will still have the potential for more power.

also, just by increasing the displacement he will end up with a higher CR - assuming the combustion chamber volume is the same, the longer stroke will have to compress more volume into the same space.

please, HackjobTT, go back under rock that you crawled out from.