engine and drivetrain Lets Play, Identify the Camshaft! (also known as, did i get suckered)

[2002Scoob]

Hi all,

 

Sooo, back when I first got my 2002 and was hunting down parts for it with reckless abandon, the guy i bought my Weber DCOE 40's from had a bunch of parts from what he claimed were from an abandoned Alpina conversion.

 

I bought the Carbs, and he also had what he claimed to be an NOS,(but on inspection, i'm going to go with lightly used) Alpina 272 camshaft. Not super knowledgeable at the time (and still not now) I threw him some extra money for the camshaft as well. I have yet to find any documentation online about Alpina Having a 272... which is why I'm a bit suspicious. 

 

 

This winter, I'm planning to do some head-work in conjunction to doing the DCOE 40 conversion, and had thought to install this cam, or perhaps ditch in in favor of a more aggressive Schrick cam.

 

But... I would like to confirm its identity if possible, which is why I'm asking. 

 

There's tons of markings all over this little guy-

 

Toward the Distributor end, there's a square with a 364 stamped into it

and an odd looking shape opposite it- Kinda looks like a butterfly.

Further down from that are the numberals- R118 followed by a possible indistinguishable symbol, and then what could be either 0003. (upsidedown 3?) or 0063.(upside down 3?)

Down the shaft further, there is a highly embossed 4

And at the end mounting to the cam gear, there are lathe centering marks (evidence of a re-grind, perhaps?) a 101, and a barely distinguishable stamped figure that looks like a Wankel Rotor with a circle and an 'S' in the middle. 

 

Sooo. Parts experts out there, what's your thoughts? Do I have a piece of junk, something special, or did I end up with a stock camshaft... haha.

 

[2002Scoob]

Lift is looking like ~7.1mm

[AceAndrew]

The casting numbers are not significant.  The "w" is the manufacturer stamp and is found on a number of oem/motorsport cams.

Please take a caliper and measure the height (tallest) and the base circle (shortest) portions of one of the lobes.  This would give us a better indicator.

A conventional 272 grind is pretty negligible. The nose marks do tend to back up the previous owner's claims though.

[2002Scoob]

The casting numbers are not significant.  The "w" is the manufacturer stamp and is found on a number of oem/motorsport cams.

Please take a caliper and measure the height (tallest) and the base circle (shortest) portions of one of the lobes.  This would give us a better indicator.

A conventional 272 grind is pretty negligible. The nose marks do tend to back up the previous owner's claims though.

 

Yep, I did measure, as posted above. Here's some photos. 

 

The base circle floated between 26.86 and 26.85

 

After Zeroing out, lift shows at 7.1mm

[2002Scoob]

The casting numbers are not significant.  The "w" is the manufacturer stamp and is found on a number of oem/motorsport cams.

Please take a caliper and measure the height (tallest) and the base circle (shortest) portions of one of the lobes.  This would give us a better indicator.

A conventional 272 grind is pretty negligible. The nose marks do tend to back up the previous owner's claims though.

 

 

I'm curious as to what about the nose-marks lend you to believe that PO's claims are legitimate. Could ya clue in a clueless man, please?

[AceAndrew]

Well … The marks at the nose aren't typically present on a stock camshaft (just looked at 50-60 cores). Those marks WOULD typically indicate a reground cam, EXCEPT for the fact you have a full base circle (reground cams reduce the base circle to increase lift). This would then lead me to think that whatever the grind, it was low-ish volume and done on a rough un-finished cam lobe.

 

The other clue is most Alpina/Motorsport cams have a triangle of some sort on the nose. I haven't seen that particular version before but it is certainly a triangular mark.

 

Stock lift in reality is right around 6.83mm (with a bit of variation). So your lift and full base circle would further back up the previous owners claim. Unfortunately a conventional 272-spec cam would hardly be worth running as I kind of doubt you would be able to feel any difference.   

 

Hope that helps.

Edited October 27, 2015 by AceAndrew

[2002Scoob]

It most certainly does! Thanks Ace!

 

There's no chance it could be a diff. degree camshaft, perhaps something more aggressive than 272, is there?  

 

Everything I've found suggests that Alpina typically used a 300degree camshaft.

 

I'm guessing there's no way to really confirm this without some speciality gauges.

Edited October 27, 2015 by 2002Scoob

[markmac]

Once upon a time I had an AlpinA 300 cam (small bearing) not the factory Sport 300, I really didn't take the time to check the markings on it, I do know that they didn't "logoize" like that.  It may have had some numbering - probably did so ti could be identified.  At any rate, AlpinA did in fact offer a 272 cam that was homologated for Gruppe 1 racing.  This shows all the various 4 and 6 cylinder cams (Alpina and BmW), the 272 from this list (which is a well worn, copied, faxed, copied, wrinkled document) has slightly different specs than yours, but then yours may have been re-round etc.,  BTW, they used that 272 cam with Tii's.

 

 

www.alpinabmw2002.com

[2002Scoob]

Man! Well look at the brains on this guy Awesome.

 

Well. Nice to know my seller was as honest as I hoped. 

 

I'm still leaning towards selling or trading it for something a little more aggressive, and a better match for the DCOE 40's. 

 

If anyone is interested I could bring it back to the Bay Area when I'm around for Thanksgiving.

[TobyB]

Don't get too bummed just yet-

 

yes, lift is one of the things that identifies a camshaft.  But duration also has a big effect on how much power and torque a cam can deliver.  As does timing.

 

If your cam gets the valves significantly open sooner than the stock cam, it will flow better, and potentially build more power/torque at lower revs.

The factory cam is pretty good, but that doesn't mean it's optimum.

 

The homologation is nice, too- if they were lift- limited, then they may have tried to maximize duration to make more power while staying 

within the rules.  It's one of the classic cheats- take a cam blank, grind it to stock lift but longer duration with faster valve opening

and closing.  It "measures" legal with a micrometer, but adds real power to an engine.  It's also one of the reasons roller cams are 

popular- you can snap the valve open faster, flow more, and get power while reducing sliding friction.

 

You can take it to a cam shop and have them 'degree' it for you- they'll give you the dimensions of what it does.

Better still would be to take a stock cam for comparo- they will then be able to tell you 

"you'll make real power here and here" or "these things are roughly the same, but the horsepower curve will be different" or something along those lines.

 

I think it's cool.

 

t

[2002Scoob]

oh i'm not bummed at all! On the contrary. I was skeptical at first but buying it was a small gamble anyway, I'm happy it's turning out to be something kinda special. 

 

I'm not sure of a Cam shop in my area and the only stock Cam i have is currently in the car, but perhaps if anyone can glean potential off the shape of the lobes, go for it!

 

[2002Scoob]

In terms of cam shape, it has a defined asymmetrical profile, with a flatter, steep face, and a more gradual sloping face. 

 

[TobyB]

That's more bump volume than the standard cam bump.  

 

Neat!

 

t

[vinntagejoe]

Man! Well look at the brains on this guy Awesome.

 

Well. Nice to know my seller was as honest as I hoped. 

 

I'm still leaning towards selling or trading it for something a little more aggressive, and a better match for the DCOE 40's. 

 

If anyone is interested I could bring it back to the Bay Area when I'm around for Thanksgiving.

 

 

he's wicked smart..............................

[GoldLion]

On 28 October 2015 at 5:47 AM, AceAndrew said:

 you have a full base circle (reground cams reduce the base circle to increase lift).

 

Bumping this thread out of interest after it was mentioned recently.  Long story short, I'm intrigued and am considering making an offer.  But correct me if I'm wrong - and keep in mind that I have no idea about this stuff (be kind) - I thought that grinding a cam only took material off the 'y axis' of the base, to increase lift?  Would this mean that the 'base circle' measured above (x axis) would remain the same as stock'?  As per pic below:

 

Tell me your thoughts,

 

Daniel