Is it worth to build high rev M20B22?

[raudonis]

There are also steel rockers from KM cams in Norway.

[nomansland92]

standard rockers are not ok at 9000rpm for an extended period. gotta do it right if youre gonna do it. the billet rockers from VAC are cheaper than the roller rockers, then there is the heavy duty rockers (cast) that have been around for a few years now.

I always wondered what are the heavy duty cast rockers good till with stock springs?

[Jasu]

standard rockers are not ok at 9000rpm for an extended period. gotta do it right if youre gonna do it. the billet rockers from VAC are cheaper than the roller rockers, then there is the heavy duty rockers (cast) that have been around for a few years now.

I know that they may not last long, the same applies to any other.
Usually a hard piece falls out, that's a problem of billet ones. HD rockers again are not very equal quality. And I've seen a lot of them broken, unlike BMW's original.

Of course, that roller kit might be the best option. But the information about those just does not exist.

edit. typo

[Jasu]

There are also steel rockers from KM cams in Norway.

Same that Enem ones.
I have not heard any good of them. Are indeed cheaper than originals, so can not expect miracles.

[digger]

dont know what you mean by a hard piece falls out

if you cant afford the RHD roller rocker setup then with conventional cam VAC billet will be the go. find a good cam grinder and make sure the pads are upto spec finish wise and squareness to the lobe as the PPM ones are junk in this regard and certainly need refinishing if you want them to last.

[raudonis]

dont know what you mean by a hard piece falls out

I think he meant

http://savarturbo.se/stuff/images/robban_e21_turbo/ppm_rockers/dsc_0968.jpg

[digger]

I think he meant
http://savarturbo.se/stuff/images/ro...s/dsc_0968.jpg

are those VAC's parts? or PPM?

edit those arent VAC those are the junk from PPM

http://www.bimmerforums.com/forum/showthread.php?1710628-FS-Miller-W-A-R-Chip-VAC-billet-rocker-arms-292-Camshaft-19-injectors-etc

the feet on the PPM rockers are poorly done, they aren't square and hence you will get eccentric load which does all sorts of nasties

[digger]

other sources

http://www.racehead.com.au/?wpsc-product=bmw-m20-complete-roller-cam-kit

http://www.tommisbillet.com/fi/tuotteet/tuotteet-automerkeittaein/bmw/muut-osat/keinuvivut

[mr2peak]

I'd love to see a honda K20 hybrid in an E30. High revving, proven, relatively cheap, and tons of potential. Basically a modern S14

[TobyB]

The KM rockers for the M10 seem to hold up pretty well up towards 9000.

But the ONLY times I've ever broken even Febi rockers with voids has been when
the spring pressures went soft. I think that as long as the valve isn't allowed to float,
the rocker isn't the weak point. Up to the point where the valve spring breaks the
rocker on its own, or wipes the lobe from the cam, anyways.

But I'm just some guy with an internet connection...

heh

t