Camshaft identification

[Kristian Jonsson]

This is supposed to be a Holbay camshaft. Any opinion?
Lift:7,9 mm.
981186
C MC24794

 

[spmdr]

I was JUST going thru some Alpine cams also, mere moments ago!

I have that same cam, I think. My cam has 1981186

I also have a cam MC24794 71981553

Both of the above cams I think are Holbay H120.

With specs of:
233 deg @.050, .320 lobe lift, 103 deg lobe centers.

As far as I know, here are other Alpine cam ID numbers:

1592 MC22539N 1980735
1725 MC24235M 1981080 219 deg @.050, .298 lobe lift, 110 lobe centers.


I have an unknown cam with the ID of 71981552


BTW, I was just about to start a thread about camshaft ID AND specs.

It seems all the other info I have seen about Alpine cams seems to be incomplete.

It may have some specs, but not all (lobe center info) and No ID...

Or some ID and some specs, etc.


But when you are talking to a camshaft source, the numbers they talk are:

Duration @ lift, Max lobe lift and lobe centers, to start.

Valve lift numbers can change with different rocker arm ratios.

Opening and closing numbers, even though commonly listed, are less meaningful because they change depending

on how the cam is installed.

Of less importance in the cam numbers world is the Installed degree(s) , usually advanced .


Let's continue this thread to "info exhaustion."


For example, I'm looking for a SS sold H120 "replacement" cam, but I don't know how to ID it

outside of the specs it should be.

AND, does anyone know the ID of a "Series 7" cam?

DW

 

[spmdr]

Some other cam info, found elsewhere:



Note, no lobe/valve lift numbers.

 

[spmdr]

From the Marque.

 

[RootesRacer]

From the Marque.

View attachment 23781

Good info, I dont buy the lobe center data on the highlighted H120 and E128 cams, those figures are wonky/

 

[Kristian Jonsson]

This is really interesting. After this weekend I will come back the another cam that I dont know what it is. Less lift then the Holbay, but more then the 1725 Alpine.
What about the Hunter GT? Any info on that cam?

 

[Kristian Jonsson]

I asked Newman Cams in UK about reprofiling one of my Holbay or Hunter cam to something useful.
Hunter head, DCOE, not more lift then 0,320, 5500-6000 rpm, 110 -120 bhp.
The Hunter head will be OK.

 

[Kristian Jonsson]

I have the idea of using the Harr. Le Mans camshaft in the 1725 engine, just because the Harr. Le Mans car was running so sweet. But I still havent been able to get that oil pump gear off.

 

[spmdr]

Does anyone have the specs of the Delta KB regrind?

 

[Alpine 1789]

Does anyone have the specs of the Delta KB regrind?

This might help: http://forum.sunbeamalpine.org/index.php?media/kb-grind-worksheet-from-tom-h.789/

 

[alpine_64]

This is really interesting. After this weekend I will come back the another cam that I dont know what it is. Less lift then the Holbay, but more then the 1725 Alpine.
What about the Hunter GT? Any info on that cam?

Hunter GT cam was basically the 1725 alpine Series V cam.

 

[Jay Laifman]

Hi Dan. I have some numbers. These are really old notes.

I'm not sure where I got numbers for Sunbeam Specialities H120 - but I got them somewhere, and my notes indicate that mine was measured to be close to the SS version, but longer durations. Take them with a grain of salt. I don't think they were accurate.

So here is what I have:

Holbay H120. Intake open 44 BTDC close 51 ABDC; Ex open 60 BBDC close 26 ATDC
Holbay H120 from SS. Intake open 27 close 60; Ex open 62 close 25
Mine (SS H120 as measured - I think). Intake open 25 close 65; Ex open 60 close 30
E128. Intake open 35 close 60; Ex open 62 close 30
Elgin/Delta/Isky. Intake open 22 or 23, close 62, 63 or 65; Ex open 62,63 or 65, close 22 or 23.

 

[Jay Laifman]

And FWIW, I see in my notes that I found H120 numbers than say the exhaust starts at 69 and at 60, and I did not resolve it then.

The Chrysler UK WSM.149 for the H120 says cam: 58 - 66, and 84 -40.

The Holbay company sales brochure says E128: 35 - 60, and 60 - 30.
It says Hunter GLS/Rapier: 58 - 66, and 84 - 40. Lift .320"

The article in Motor, Dec 14, 1968 on the Sunbeam Rapier H120 says: 58 - 6?, 84 - 40. (the intake close number is messed up. It could be a 0 or 9 or 6.)

These are all from copies of each that I have.

 

[spmdr]

I had a chat with Delta cams today.

The above "KB" specs made me think that all "KB" Cams would be defined as spec numbers including a 106 Lobe Center number.

For example, As far as I know, an Isky SB2 cam has fixed spec numbers, all of the SB2 cams are the same.

Delta pointed out the "KB" is just the lobe regrind shape.

A Delta "KB" cam COULD be ground on a wide range of lobe Centers ( the LC can be changed +- 4 deg, from the original core LC, I think ),

depending on the cam sent to be reground and/or what is requested/specified.

They said IF the LC is NOT specified, it is ground on the original LC of the core.

So when you talk about a Delta KB cam it really NEEDS to have the Lobe Center number added to the spec numbers to know what the given cam is.

Cams with wide Lobe Centers (110+) tend to have wider, flatter Torque curves.

Cams with narrow Lobe Centers (108 -) tend to have more peaked torque curves, but with bigger peak numbers.

I, for one, really want to see some BIGGER Peak numbers, ... for a Change!

 

[spmdr]

In an effort to ID Cams, I'm giving this thread a bump in hopes of adding Cam ID numbers.

Go through your cam pile and look for interesting cams.

Still looking for ID of later Cams, Cams from Sunbeam Specialties, etc.

DW