WTB - Paul Burke N21 cam

HB Chris said:
Thanks Sven. Mike’s 3.8 stroker with a Shrick is smoother but maybe it’s due to the motor. Markos is going to install a shaker hood on his coupe with that 300 cam. :cool:
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I ran the n31 in my 3.8 which I understood to be more of a hot rod cam vs the n21. I think the mega squirt, intake, head work, and headers contributed to it running smoothly. The engine pulled right up to redline which is also what I was looking for.
 

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A couple of comments about cams....

The B355 cam is 264 duration. Known as the “K” cam.
originally installed in euro big 6 motronic engines and then installed in the USA in b35 engines.

The Dbilas cam are known for higher lift than the available Schrick cams.
Installing a 292 Dbilas cam in a m90 engine with stock pistons (flat top) can produce a $2000.00 repair bill in seconds. Decked blocks and milled old heads are trouble. Clay is your friend in this case and reliefs are even better.

The smile you will have from that combo can be the six smiles left imprinted on your pistons

Duration: : 290
Peak timing: : 108
Valve lift: : 11,0

that lift is 3.7 % higher than the early Schrick cam.

There are actually 2 m30 cams and they are quite a bit different.
The early m30 Schrick cam for distributor engines was a 282/282 cam with symmetric cam and valve lift of 8.4 and 10.6.

The next generation m30 cam was the 284/280
asymmetric cam and valve lift of 8.7/8.6 and 10.9/10.8

about 2.8% more lift and more duration on intake/less on exhaust.

The ideal is to buy a Motronic cam and convert it to distributor drive for best performance if you want period correct appearance. The big nut from BMW is the answer.

As always the key to a smooth idling mild street cam is a high idle.
1050 rpm will give you a nice idle.



Paul’s cams were great unless you got one of the ones that was indexed for the rotor flange with the locating pin 20 degrees off.

Looking at Pauls numbers for valve lift you can see he was a friend of lift and why cam timing at the cam gear was critical on his cams.

My last Burke cam dyno was 148 hp until I cut off the pin and hand indexed the rotor.

Paul is a wonderful guy and it’s a shame he’s not still involved in the BMW world.
He knows a ton about engines and taught me most of what I know.

Years ago Peter and I offered to fund a large cam blank purchase for him from Turkey? and he graciously and wisely declined. I believe at current demand he would have been still sitting on half of those cams.
 
i want to say that it was around 2017 or so. as i remember he pretty much quick making them after that. my understanding is that there are also problems with that cam with the m90 engine.

The typical aftermarket cam used by most people is the Schrick 284 - there is a difference in the cam dependent on what type of distributor your engine uses. as i remember, the b34 / b35 and i believe the m90 (not sure) use a different cam than the m30 b30 / b28 with the traditional distributor.
 
2016 ?
I have a receipt for a build from then.
recommend you not install unless you put on a Camdoctor first.
at the end of sales there were problem cams being sold.
 
The cam is already installed in my M535i. My 10:1 engine I built for my other E28 with a Schrick Cam didn't seem to idle as low on the stock euro 061 DME comparatively. I can tune the chips though so I got it sorted out, but was just curious if this was something I should look deeper into. IIRC the reciepts are around 2013-2014 so I should be okay. This engine has never felt as torquey as with the Schrick but it pulls hard up top. The receipts from Paul said it had an adjustable cam gear. I embarrassingly haven't popped the valve cover yet to check to see if installed/where it is set.
 
Rotate your cam gear 1/2 tooth- you might end up with a more balanced output.
 
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