N52 performance cams

[justpete]

Originally Posted by TheAxiom

Any word?

Miscommunication. He found some on ebay but wasn't sure it was worth the investment. I apologized for not making it more clear I would buy the cams if he found some. He found a number of sets on ebay, my shop hasn't got back to me yet, and there's always the new parts option.

[justpete]

Originally Posted by MarkkyyMan

Hollow Cams+ Regrind= Sounds like trouble..

Dunno, maybe. That's why I want to get a set of cams to them for evaluation. Seems like it's worth a shot anyway.

[chris82]

Originally Posted by 3002 tii

Don't know how long ago this was but I heard Mike left VAC few months ago and it hasn't been the same ever since. My experience with VAC products are ok, but I could never get a hold of anyone from service (for the one or two "major" jobs I was considering to bring my car down for).

I agree, UUC is the worst. Terrible customer service, products always on backorder and their in-house products lack serious quality control. Barely reachable by phone and always quick to finger point to user/installer error rather than acknowledge their own fault. I prefer Rogue/VAC's expensive parts over UUC's crap quality products - and that's saying a lot.

Mike was really great for VAC. If you're dealing with stuff through him it got done pretty quickly. Unfortunately he left to start another business or something along those lines. As for service, it really depends on who you contact. I've gotten email responses from some of their guys in literally minutes, others, much longer lol.

Funny thing with UUC. VAC ordered a SSK for my brother's 335i from them, and UUC sent the wrong part # THREE times in a row after VAC repeatedly told them it was the wrong part number. What a nightmare, UUC really does suck lol

[justpete]

Ordered cams today, supposed to be in tomorrow morning. Will ship to Todd and see what he has to say. FYI

[chris82]

Originally Posted by justpete

Ordered cams today, supposed to be in tomorrow morning. Will ship to Todd and see what he has to say. FYI

Awesome!

[Taskmaster]

You're my hero.

[Freon]

Originally Posted by TheAxiom

Not at all. Lifters will compensate for the smaller base circle, it should be fine.

Lifters/shims/etc. apply to all regrinds, hollow or not. I think the concern when pointing out hollow cams specifically is material strength after the regrind. They start with less material, and regrinding may or may not leave the cam rigid enough or strong enough.

I'd also still be weary of the complexity of Valvetronic making the profiles hard to design. It's not as simple as a standard DOHC setup where the cam directly presses on the lifter, or even a pushrod or SOHC with a simple rocker arm.

[justpete]

Originally Posted by Freon

Lifters/shims/etc. apply to all regrinds, hollow or not. I think the concern when pointing out hollow cams specifically is material strength after the regrind. They start with less material, and regrinding may or may not leave the cam rigid enough or strong enough.

I'd also still be weary of the complexity of Valvetronic making the profiles hard to design. It's not as simple as a standard DOHC setup where the cam directly presses on the lifter, or even a pushrod or SOHC with a simple rocker arm.

This is all exactly true but no way to know until they get a cam to evaluate. If it isn't possible then at least we'll finally know for sure. If it's possible I'll end up knowing they're not reliable if the engine goes bang. It's a science experiment...

[631twentyeighteye]

Can't wait to see where this goes.

[justpete]

Picked up the intake cam this afternoon, the exhaust cam didn't make it but will be in tomorrow morning. Here're some pics of the lobes and the ends. The minimum thickness of the lobes is right at 0.200" and the wall thickness of the cam itself is quite a bit more than I expected.

[andrey_gta]

Nice and Shiny, lets all hope they can be reground

[Taskmaster]

Is it heavy?

[justpete]

Originally Posted by TheAxiom

Is it heavy?

Oh yeah, much heavier than you'd expect. It'll survive the regrind process without the slightest problem. The only issue remaining is surface hardness changes induced by the grinding which Todd is very familiar with and aren't really a worry although they will limit how much can be ground off. There doesn't appear to be a way to carburize or otherwise reharden surfaces without destroying the cam as far as I can tell anyway.

I'm going to request a performance grind to work with a stock engine so I can have them installed and evaluated on the dyno and the street. I talked with the guys at the dealership yesterday and the cost of a full race engine rebuild will be less than I thought so with custom pistons, race valves, head work, etc., the cams will be reground again to accommodate higher than stock lift, 8000rpm redline, and 11.5:1 compression ratio. That'll yield a part everyone can order for street use and one for higher performance assuming there's anyone else out there as stoopid crazy as me who wants a street/track perf'ed N52. And really what're the odds on that??

[andrey_gta]

Originally Posted by justpete

I talked with the guys at the dealership yesterday and the cost of a full race engine rebuild will be less than I thought so with custom pistons, race valves, head work, etc., the cams will be reground again to accommodate higher than stock lift, 8000rpm redline, and 11.5:1 compression ratio. That'll yield a part everyone can order for street use and one for higher performance assuming there's anyone else out there as stoopid crazy as me who wants a street/track perf'ed N52. And really what're the odds on that??

You can do a Stroker kit, or look into one if you go that deep into a rebuild
I would email Noelle/Hartage and get their 3.2 n52 330i speck kit on the reduced price after crying for weeks. Tune it under custom software though - cuz their is MSV70

[justpete]

Originally Posted by andrey_gta

You can do a Stroker kit, or look into one if you go that deep into a rebuild
I would email Noelle/Hartage and get their 3.2 n52 330i speck kit on the reduced price after crying for weeks. Tune it under custom software though - cuz their is MSV70

Well, yeah, there is that. But it's dependent on the crankshaft design, not something I want to risk really. And the cost is extreme for increasing bottom end torque while making it more difficult to raise the redline. We might knife-edge the crank but that's about as radical as I'd want to go right now.

[justpete]

Picked up exhaust cam midday today. Here're some pics. The minimum thickness of the lobes is about half that of the intake cam at 0.100" and the thickness of the camshaft itself is about 0.132" as measured with a pair of calipers.

[andrey_gta]

@justpete how can you tell which one is inlet vs exhaust cam?

My part search for some reason got them backwards- thin as inlet, thick as exhaust..

[justpete]

Originally Posted by andrey_gta

@justpete how can you tell which one is inlet vs exhaust cam?

My part search for some reason got them backwards- thin as inlet, thick as exhaust..

Thanks, you're right. I checked RealOEM and the thin is the intake and thick is exhaust. Thin is the p/n ending in 663 and the thick is 665.

[Taskmaster]

I'm nervous, I'm not sure there is enough material to grind away at to increase lift.

[justpete]

Originally Posted by TheAxiom

I'm nervous, I'm not sure there is enough material to grind away at to increase lift.

Understandable. I took some quick measurements of the lobe on the end and it looks like max diameter at the nose is about 1.427" and base circle diameter at ninety degrees from the heel is about 1.182", more or less. This translates to a difference of about 6.22mm so the maximum lever arm multiplication would be about 1.6X at a maximum lift of 10mm.

Except the nose lifts the valve so I'm guessing removing material from the heel and calibrating this as the closed point on the Valvetronic eccentric rotation increases the valve lift by the lever arm multiplication times the increased diameter difference.

A 1mm lift increase would then require grinding off about 24.6mils from the heel, only 25% or so, doesn't seem too extreme but I don't have any real idea to be honest.

All this sound right?

[Taskmaster]

Uhhh, let me plot this out.

Edit. Looks good, I got the same numbers as you.

[Taskmaster]

Actually, yeah, That isn't as an extreme change as I thought! Seems very likely!