Cam Question

[LeftAngle]

When I pulled 659R out of the barn it had been living in, the PO’s cousin told me the PO had put in a new cam.   Not wanting to pull the motor apart, I left the cam question unanswered. 

Now as long as the motor’s apart can anyone give me any information about this cam from what’s stamped on it?   I’m totally out of my element here but as long as I have access to it, I might as well try to answer the question.  Is this a stock R16 cam?  Do the numbers or stampings give any useful info if it’s not?  Thanks
Bruce

[jbcollier]

Hard to tell for sure from low rez photos but that cam does not look happy.  What do the followers look like?

If the PO put a "cam"in it, it would probably be a reground stock unit.  Brand new cams are very expensive.

[LeftAngle]

Sorry... I tried upping the resolution but the website rejected them.  No matter.  The cam’s as happy as it’s going to get.  The surfaces and followers are fine.   Not having seen an original cam from an R16 I was hoping someone could tell me if it’s original equipment or not.   

[BDA]

Here are some ways of resizing your photos so they can be included. There should be plenty of resolution if you do this. http://www.lotuseuropa.org/LotusForum/index.php?topic=1379.0

[LeftAngle]

Thanks, but I do all my work on an iphone.  The latest ios update made my sizing app go all wonky so I’ll have to get another one.   

[LeftAngle]

Try these...

[LeftAngle]

They look the same to me.   The last ones were 1024, the stated max allowed.

[jbcollier]

Again, hard to say from photos but the nose of the cam in the first photo looks pitted and, in the second, rough.  Run your fingernail on the nose.  If you feel roughness, it's pooched.

[LeftAngle]

Oh... I see what you’re talking about.   That’s grease from running my fingers over the surfaces.  They’ll be cleaned (I promise) before assembly lube is slathered on.  The head will be sent out for cleaning and valve lapping so I’ll have time to straighten things up on the lower half while I’m waiting.

[jbcollier]

Glad to hear it.  Machine shops can polish cams if you have any doubt.

[GavinT]

Lefty,

You could measure the cam lobe at it’s highest point and subtract the measurement across.
This should give you a rudimentary figure as to cam lift . . provided there aren’t any fancy ramps going on.

Other than that, a dedicated cam shop should be able to trace out the specific cam spec. to fairly close order.

[BobW]

An ignorant question, perhaps, but did Lotus use the stock R16 cam?

[jbcollier]

Not for the 1470.  The 1565 was a federalized engine so it used a stock Renault cam.  The 1470 was a marine engine so the cam was "stock" but not stock R16.

[LeftAngle]

This was an unintended teardown of the engine.  If I have time , I’ll have the cam specked out.  I did find a photo of an R16 cam online with the number “19” cast on it.   Mine has “23” on it.   I don’t know what those numbers mean unless it has something to do with lift angle.  Evidently the PO was beefing the motor up since the piston crowns peek into the firing chamber and quench areas flush with the lower portion.  I don’t think these are stock.  I ordered a NOS water pump off of ebay.   The old one looks tired and the PO had stuffed sealant into the weep hole... I’m guessing to stop it from dripping.  A new one should last as long as I do.  Next week I’ll take the head over to the town’s machine shop to have it cleaned and the valves reset. 

I’ll post picttres on this thread as I get further into it.

.

[jbcollier]

AFAIK, the flat top pistons run around 9:1 compression and raised top piston 10.25:1.  The raised top pistons were stock in the Europa.

Cam casting numbers are seldom related to the actual grind.