N52 performance cams

[justpete]

Searched, didn't find anything definitive other than locking Valvetronic at max lift and replacing the OE DME with a Motec ECU.

Cat Cams offered to develop a Valvetronic compatible performance cam if I could send them a functional cylinder head and Schrick responded with links to their catalogs that are 404 dead. Nothing online but thought they might have something off-catalog. VAC didn't have anything but I think Cat Cams makes all their cams anyway. Turner sells Schrick but doesn't list anything just like Schrick's site.

Anyone have some suggestions where else to look? Or know of existing Valvetronic compatible performance cams? TIA

[andrey_gta]

Didn't Schrick have some kind of n54 cam on their german catalogue that looked as if it was mis-labelled and maybe was for a n52. There are images that exit on n54 boost of a n52 and cams in development by schrick from years ago
@TheAxiom was sniffing around that thread

I think Valvetronic cams would be awesome - if there are enough committed people - look at the AA header pre-buy list

[chris82]

I had thought VAC made some cams for an N52, a while back though. I think they were sending them to a race team or something.

[andrey_gta]

VAC has reinforced Pistons or did on their page

[631twentyeighteye]

As long as it kept the valvetronic i'd be interested in cams. I just wish a manufacturer was interested.

[andrey_gta]

Can we not get OEM spec cams reground for more lift or other features?
If this is possible & desirable - its easier than gettign a company to make custom ones - n52 cams already are as light weight as possible

[justpete]

Originally Posted by andrey_gta

Can we not get OEM spec cams reground for more lift or other features?
If this is possible & desirable - its easier than gettign a company to make custom ones - n52 cams already are as light weight as possible

But it would require adding material to the cam lobes so they could be reground for more duration and lift. Likely to require different pistons for clearance, etc. Gets complicated if increasing compression ratio. Ain't cheap either way though.

[andrey_gta]

Does it always have to add material?
I was referring to these e36 cam regrinds http://www.westcoastriots.com/

[justpete]

Originally Posted by andrey_gta

Does it always have to add material?
I was referring to these e36 cam regrinds http://www.westcoastriots.com/

Sure they don't add material? Sounds like they don't add lift but maybe it turned out a better profile could be ground without adding any or very much material, dunno.

BTW, turns out I pinged VAC but never heard back so I pinged em again.

[Freon]

"Regrind" usually involves cutting the base circle of the cam, then using thicker shims or buckets to bring lash back to spec. This increases the peak lift on the camshaft by the depth of the cut. Then consider any rocker arm ratio. Just a few millimeters can be significant.

This is probably a nightmare with Valvetronic due to the extra mechanical complexity.

It doesn't seem common practice on modern engines.

[justpete]

Originally Posted by Freon

"Regrind" usually involves cutting the base circle of the cam, then using thicker shims or buckets to bring lash back to spec. This increases the peak lift on the camshaft by the depth of the cut. Then consider any rocker arm ratio. Just a few millimeters can be significant.

This is probably a nightmare with Valvetronic due to the extra mechanical complexity.

It doesn't seem common practice on modern engines.

Thanks! Makes sense, should've thought of that.

[Taskmaster]

Originally Posted by andrey_gta

Didn't Schrick have some kind of n54 cam on their german catalogue that looked as if it was mis-labelled and maybe was for a n52. There are images that exit on n54 boost of a n52 and cams in development by schrick from years ago
@TheAxiom was sniffing around that thread

I think Valvetronic cams would be awesome - if there are enough committed people - look at the AA header pre-buy list

Dead end apparently - I asked VAC and they said they would investigate, haven't heard back from them since.

Regrinds might work, but who will be the first? And the cams may be hollow and have less material to remove from the base circle.

[Suprgnat]

Originally Posted by TheAxiom

Dead end apparently - I asked VAC and they said they would investigate, haven't heard back from them since.

Regrinds might work, but who will be the first? And the cams may be hollow and have less material to remove from the base circle.

They are definitely hollow ("hydroformed") and there's not much meat left to grind.

[justpete]

Heard from VAC this afternoon. They have blanks apparently and are waiting on at least duration, if I understand them correctly. I've asked if there is an active design going on and what can be done to help.

[Taskmaster]

In theory, you could have material added to the lobe to increase the effective lift/duration - but I like the idea of blank cams more. One guy saw 10-15whp gains on his M54 E46. And that was with an off the shelf tune and stock crappy heads. Who knows what our motors can do.

[justpete]

Originally Posted by TheAxiom

In theory, you could have material added to the lobe to increase the effective lift/duration - but I like the idea of blank cams more. One guy saw 10-15whp gains on his M54 E46. And that was with an off the shelf tune and stock crappy heads. Who knows what our motors can do.

With an aggressive cam, lumpy high rev idle, a race radiator so it's safe to lean it out, etc. it looks like 330hp is possible but it wouldn't be a long life engine. This assumes blueprinted and balanced, pinned bed plate, knife edge crank, custom pistons, flowed head, unshrouded valves, hollow race valves, heavy springs, three angle valve grind, increased compression ratio, 100 octane race fuel, etc. Might be able to get closer to 300hp without making a total racer out of it. No idea what could be had without custom pistons to clear higher lift on the intake.

[Taskmaster]

Originally Posted by justpete

With an aggressive cam, lumpy high rev idle, a race radiator so it's safe to lean it out, etc. it looks like 330hp is possible but it wouldn't be a long life engine. This assumes blueprinted and balanced, pinned bed plate, knife edge crank, custom pistons, flowed head, unshrouded valves, hollow race valves, heavy springs, three angle valve grind, increased compression ratio, 100 octane race fuel, etc. Might be able to get closer to 300hp without making a total racer out of it. No idea what could be had without custom pistons to clear higher lift on the intake.

The cams he had were pretty mild. 264/248 Shrick (advertised) versus the 240/228 stock cams I believe. Shrick made 272/254 cams that maxed out the vanos unit I believe, those were a bit more aggressive and created a lope at idle.

Mild cams with 11mm lift and more duration would probably still be streetable and have no negative side effects.

[justpete]

Originally Posted by TheAxiom

The cams he had were pretty mild. 264/248 Shrick (advertised) versus the 240/228 stock cams I believe. Shrick made 272/254 cams that maxed out the vanos unit I believe, those were a bit more aggressive and created a lope at idle.

Mild cams with 11mm lift and more duration would probably still be streetable and have no negative side effects.

Sounds reasonable. I'm looking for marginally streetable cams for the track. Expecting to rebuild the engine as described but will need VAC's help obviously including head work and custom pistons, etc. And to have my head examined I'm sure...

[Taskmaster]

Originally Posted by justpete

Sounds reasonable. I'm looking for marginally streetable cams for the track. Expecting to rebuild the engine as described but will need VAC's help obviously including head work and custom pistons, etc. And to have my head examined I'm sure...

I wonder what the headflow is on the N52! Still, M50 intake manifold would probably be enough to add some power, the problem is making it fit. Can't wait to see what you can manage.

[justpete]

Originally Posted by TheAxiom

I wonder what the headflow is on the N52! Still, M50 intake manifold would probably be enough to add some power, the problem is making it fit. Can't wait to see what you can manage.

Well, there is that one running a custom manifold with E36 ITBs (I think) with a flowed stock head iirc. We'll see but I'm guessing VAC has a lot better things to do.

[Taskmaster]

Originally Posted by justpete

Well, there is that one running a custom manifold with E36 ITBs (I think) with a flowed stock head iirc. We'll see but I'm guessing VAC has a lot better things to do.

Itbs are a nightmare to tune. Well, unless you have a tuner. I feel a solid 15-20whp with cams and a custom tune can be had, especially with a good clean up of the head.

Did VAC give a ETA for those cams? You could buy blanks and have Kelford, Cat, Crower, etc make custom grinds.

[Taskmaster]

A custom tune would do wonders for you - have you seen that N51 dyno?