Questions about my "budget" stroker build....

[LavaSurfer]

I scored a M20 from a 325i for next to nothing for my 325e. And I'm throwing around build ideas in my head. Keep in mind this is a daily driver/fun car. I would like it to be "reliable", but I don't mind getting under the hood and messing around with it here and there.

I'm looking at sourcing a M52B28 crank, eta rods, stock i pistons, Schrik 284 cam, Miller MAF conversion with the WAR chip (i would like the tuneability this offers, but don't think I want the headache of a MS or something similar), and the ebay header and catback exhaust that's on my eta now.

The questions I have are mainly to do with the camshaft. With the added displacement would I be able to run a cam larger than the 284 without any major low end drawbacks?

Also, any suggestions on some companies that sell rebuild "kits" (bearings, rings, gaskets) for a reasonable price

[nando]

yes, but you realistically don't want much more than the 288. And it could really use some special port work to cut down on turbulence above 11mm of lift (I don't know the specifics on this one, but there's a thread with flowcharts on E30tech).

[Danny]

I was just about to ask the question.

I'm mid way through collecting parts for this exact build.

[MR 325]

If the head's off and you're building the stroker, I would definitely port the head as mentioned!

[nando]

this thread:

http://www.e30tech.com/forum/showthread.php?t=75938

you want to copy whatever valve seat cut he did.. even the 284/272 would benefit.

[Danny]

But the M52 crank + I pistons/eta rods puts the pistons at the stock deck height.

Wouldn't an adjustable cam gear suffice?

[nando]

hmm? an adjustable cam gear isn't going to fix intake port turbulence above 11mm of lift. the 284/272 and 288 both have 11.4mm of lift. ;)

and you don't want to use a cam gear adjustment to fix valve clearance. you use that to set the timing of the cam for the best powerband.

even if your pistons are at stock height, that doesn't mean you have enough clearance. a stock 2.5l doesn't have enough clearance for either the 288 or 284. it will hit the intake valve at TDC.

[Danny]

Ahh I see, I read the valve seat as valve relief. Hence the WTF moment.