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M54B30 NA Beast Attempt. Help Needed.

5K views 6 replies 5 participants last post by  shadow032 
#1 ·
Hey guys,

I'm currently attempting to build an NA M54B30 on a budget and I need your help. Building engines is not a skill I have mastered yet and I'm going far and wide outside my comfort zone, learning as I go.

So far I've got the block bored to 84.5, balanced new pistons, gaped the piston rings, plastigauged the main and rod bearings and did extensive head work.

I'm trying to figure out how valve springs rates relate to valve float at high rpm in these engines and what is high rpm for an M54 engine. I've seen claims that stock m54 valve springs are good for around 7000+ rpm. Also, I've read that the M50 non-vanos engines supposedly had stiffer valve springs and they could be used in the M54 head:argue:. Recently I found a local place that offered me a regrind of my original B30 cams, which got me thinking about supporting valve train upgrades (budget ones:thumbsup:). Do you think M50 NV valve springs will work in the M54 head?

My next question is regarding cam regrind and piston clearance in vanos. I'm going for 11,5:1 CR, so I will need to deck the block with 0.08. My new pistons are 0.02 lower than the stock B30 pistons and also have bigger valve reliefs (around 0.12 deeper, much like the B25 pistons). How much cam do you guys think I can run without loosing vanos?

Thanks i advance.

P.S. I appologize if the questions I have are already answered in another thread and I've missed it. I tried searching and reading before posting this.
 
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#2 ·
Well first of all stock valve float occurs in M54s at around 7200+ rpm; I read that 7500 is where it happens awhile back but some other sources say above 7200 it's bad. 7000rpm is doable on stock valve springs. I assume you know that the m54 doesnt make any significant gains at those rpms, but depending on your cam that could change.
I'm not sure if non vanos m50 springs fit, but maybe someone else can chime in. I dont see those being very much stronger than the m54 springs even though it's well known they are stiffer.
However, you need to remember that there are bad harmonic issues with the M54B30 above the stock 6500 rpm redline. You can get an oil pump solution that gets rid of the stock left hand thread oil pump nut that backs itself off. Basically replaces the oil pump sprocket/shaft. Check out Seems Legit Garage. The nut with the safety wire can work too, but if it's going to see constant high rpm as a dedicated track car, I would go for something a little better. Also you can get a Super ATI damper that replaces the stock harmonic balancer and can really help get rid of the nasty harmonics.
 
#4 ·
Thank you for the fast replies, guys!

I'm aware of the oil pump problem and I was planning to J-B weld the nut and add the safety wire too, plus I found a suitable chain tensioner for a WV that looks like a perfect fit. I will look up your suggestions for upgraded pump shaft and the Super ATI damper too. In that regard, I see a lot of people here running 10W60 in their attempt race engines and I wonder if that has anything to do with oil pump failure at high rpm, since heavier oil might stress the pump more. :hmm:

I'm really struggling to find info regarding the m50 nv engines and how they rev, and never had any experience with one, as they happened before my time. :bump: However, if it is confirmed the valve springs from these engines are just a touch stronger and they fit, they will do for me.

If someone can touch on the valve clearance issue with the decked block and regrind cams, that would be awesome.

Thanks once again for your help so far. This proves that here is the place to be for these stuff. If all goes well with my plans and I learn more, I promise to contribute back! :thumbsup:
 
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