Unknown camshaft

[Kristian Jonsson]

I have just taken a Holbay cam out of one of my engines. It seems OK. No wear or unpleasant surfaces. 7.8,m.m. lift.
I presume it is was a Holbay but it has a 7.8 m.m. lift (0.307 inches). Holbay is supposed to be 0.320 inches.
So if it's not a Holbay cam, what can it be?

I did only test run it and it did run bad with a DCD 28/36
The red stuff is Red Line assembly lube.

Have anyone used this camshaft or the Holbay on a standard engine with some kind of carburettors and made it run. (Reasonable)

 

[puff4]

This discussion may be useful to you:

Camshaft identification

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

forum.sunbeamalpine.org

 

[spmdr]

Can you expand on "run bad" ? ....inquiring minds and all...

Also, how did you measure the lobe lift?

DW

 

[Kristian Jonsson]

This discussion may be useful to you:

Camshaft identification

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

forum.sunbeamalpine.org

That I have forgot completely!!!!!!!

 

[Kristian Jonsson]

Can you expand on "run bad" ? ....inquiring minds and all...

Also, how did you measure the lobe lift?

DW

It did only run on high revs. to low it did just stop.
I measure by subtract the high number with the smaller number.....or what do you mean???

 

[spmdr]

Most of the time it is difficult to measure Max lobe lift accurately without a fixture,

IF the cam is just loose/uninstalled.

Most solid lifter cams have clearance ramps that make measuring the base circle diameter

difficult to impossible just by laying a caliper on the minimum lobe diameter.

The point I am making is the cam may in fact be a STD H120 cam.


And, cams with a lot of duration/overlap NEED extra help with low rpms because

of the low vacuum.

DW

 

[Kristian Jonsson]

I will repeat my second question:

Have anyone used this camshaft or the Holbay on a standard engine with some kind of carburettors and made it run. (Reasonable)

 

[alpine_64]

I will repeat my second question:

Have anyone used this camshaft or the Holbay on a standard engine with some kind of carburettors and made it run. (Reasonable)

There are too many variables in your question.

If you have a holiday camshaft the holbay motor had a different distributor and head/compression etc... so your issue could easily be the ignition curve or timing are your problem... And could be quite likely .

There are guys who've run holbay motors ( full holbay setup) with stock Stromberg 150cd carbs.. and they run fine . Just a little lacking in power

Your saying a 28/36 is your issue .. yet the car is dying down low and ok under higher load... That's the reverse of under carb issue.. if the motor didn't have enough carb the higher rpm would be the issue as it starves for fuel... It's also possible you have a vacuum leak as that would cause the car to stall at low throttle but run at idle and WOT.