M30 turbo just snapped a rocker, top end advice?

[Lurker27]

I already have ARP head studs installed. I think I'm going with a stock Goetze Head gasket (stock thickness unless anyone really suggests otherwise) and o-ringing the block (copper or stainless?).

I have an M30B35 with the dual valve springs, will these be strong enough for a turbo cam? I see VAC makes a spring set, and IE does as well. Anyone know if the IE springs are crap? I know they're kind of hit and miss on quality.

[LowR3V'in]

Which cam?
If you can ask the maker what they recommend that would be best.

Get the IE HD rockers, probably never have a failure with those. :)
Maintain rocker adjustment.

[Lurker27]

Grabbed a set of IE billet rockers, even better.

Going to get a cam ground to the specs of leszi from e30tech - basically it's a B35 cam with increased lift (turbo cam, so not as much duration/overlap)

[Lurker27]

oblig. carnage pic. Let go at 2.5krpm

[VinniE30]

Get rocker locks instead of springs.

In most of the photos I've seen of a failed rocker arm one leg of the eccentric support is broken off. This suggests to me (speculation no data) that the failure is caused by the rocker "walking" down the shaft and getting side loaded by the valve. For this reason, and the fact that they are so cheap, I feel that rocker locks must be part of any budget for new rockers.

How many miles did the engine have? The rocker probably already had a crack in it; I couldn't see a perfect rocker breaking at 2.5krpm.
Do any of your other rockers have hairline-like cracks?

I think new OEM rockers are fine as long as you're not trying to rev over the limit, but like anything they do have a lifespan and cracks are bound to form after tons of miles and stress. But of corse if you have lots of money go for the billet rockers.

[Lurker27]

rockers have 300k on them. Already ordered billet + rocker locks. Getting a massive cam and going for 550rwhp

[Good & Tight]

rockers have 300k on them. Already ordered billet + rocker locks. Getting a massive cam and going for 550rwhp

How much were the billet rockers?

[ttrousdell]

rockers have 300k on them. Already ordered billet + rocker locks. Getting a massive cam and going for 550rwhp

300k is a good amount of miles for a turbo engine (assuming same mileage as rockers). I hope you put this build on the project forum. It would be a great reference for my future plans

[Lurker27]

Build thread was here, ish. Engine was rebuilt, seals and bearings. Had full compression in all cylinders and still showed original crosshatching in the cylinders. M30s don't fuck around.

http://www.r3vlimited.com/board/showthread.php?t=205514

Anyone have thoughts on what to do about valve springs? I should really probably swap out. I know M30B35s already come with the stronger dual valve springs, and so new OEM ones are an option. Should I just get the IE race springs? VAC wants a mint for theirs.

Otis, I found a used set of IE billet rockers + rocker locks for $400 and I pounced on it. I'll probably blueprint them before I put them in, just in case....IE wants $85 per

[SkiFree]

If you got them from the guy trying to hawk them on bimmerforums BE WARY. Make sure the pads are in good shape as some of them looked suspect.

I've taken the billet rockers off the site a while ago as a lot of people were not taking care of them the way they should have been. With newer oil possessing no (or low ammounts of) zinc/phosphorus I'd make sure you run a proper additive on break in as well as normal use. Some good stuff to use would be http://schneidercams.com/formula2additive.aspx

In regards to the valve springs, have you called regarding your setup?

[Lurker27]

This is probably a dumb question - but called who? I mostly asked the cam grinders I've talked to. If you are Scneider Cams (I've heard very good things) then you probably have an e-mail from me. The sense I get generally is that new M30B35 dual springs are fine for most regrinds since the valve lift is limited by how small the base circle can be, but that could be wrong...and certainly is if material is added on.

I'll definitely get that additive, I've heard of the ZDPP issue before, and simply running thicker oil (I have somewhere in my notes Pennzoil GT 20x50 is the best for zinc content, but it's pricey) is less appealing than using that stuff.

[Lurker27]

I will be double sure to check out the rockers - hopefully worst case I just need new pads on a couple.

[Myster-E]

I'll definitely get that additive, I've heard of the ZDPP issue before, and simply running thicker oil (I have somewhere in my notes Pennzoil GT 20x50 is the best for zinc content, but it's pricey) is less appealing than using that stuff.[/QUOTE]

Valvoline VR1 oil has a good amount of zinc in it also plus its only $5 a qt. and comes on sale sometimes. Great stuff use it on all my cars.

[SkiFree]

This is probably a dumb question - but called who? I mostly asked the cam grinders I've talked to.

Sorry for the response being a little convoluted, I work at IE.

[Good & Tight]

Valve lash is important also. Too loose and the bounce off the cam at high revs and break.
I've had very good results with valve lash set at .008 when the engine is warm.