Diamond B cam timing

[Synchro909]

I have 2 A engines that I have put together for touring and I'm very happy with them. I also have a Diamond B block with which I am not so happy. All three engines have a 5.5:1 head and a downdraft Stromberg carburettor from a Holden. The two A engines also have a slightly modified cam - the B has an original B camshaft - the only difference.
I have always thought the B engine was not doing as well as it should and it is thirsty. For quite a while I thought the fact that the car (1928Tudor) with a heavy sedan body and a 3.54 diff ratio was why. I have just spent 4 hours behind the wheel of this car which gave me the chance to do some thinking on the matter. Here's what I arrived at.
There are the three Cs to make an engine go - Carb, Cam and Compression. Since all engines have the same Carbs and same Compression, the difference must be the cam. I understand that the B cam is better than the A but it may not be as good as the one I had done locally for the A engines(I don't know the figures - just that is is a good thing!).
These diamond B blocks were built for Industrial/ Agricultural purposes so I wonder if because they are more likely to be running at fairly constant RPM, the cam timing might be different from a car engine.Is anyone able to confirm or refute that?
Looks like I might have one of my spare A cams ground the same as the others and put that in. Yet another job! UGGHHH!

[BRENT in 10-uh-C]

....or, the cam gear may be off on its timing. Before I would remove the camshaft, I would degree the cam in it to see where it comes in at, -and check lift on each valve.

[updraught]

A bit about Diamond timing

https://www.fordbarn.com/forum/showthread.php?t=77936

[Railcarmover]

Might not be what you think,we've all been fooled before ..I'd check tune,vac leaks and float level before tearing into it. Then if it did,Id do as Brent suggests and center on the timing gear. Anything is possible with your cam till your measure it,but Id make sure everything else is correct before I jump in there.

[katy]

Quote: "....or, the cam gear may be off on its timing. Before I would remove the camshaft, I would degree the cam in it to see where it comes in at, -and check lift on each valve."

Also possible that the B cam is worn.

[Jim Brierley]

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Ford made 3 slightly different B cams, with lobe lifts of .302. .315. and .339". Your diamond block could have any of these in it. I've even seen a G-28 engine with the A grind but it had a fuel pump lobe. If you determine it is in fact the cam, I would have a touring grind put on it. The latest B cam, with .339" lobe lift makes a great touring cam. ... or maybe your diamond block just doesn't like the GM-Holden carby??? -

[Synchro909]

Originally Posted by BRENT in 10-uh-C

....or, the cam gear may be off on its timing. Before I would remove the camshaft, I would degree the cam in it to see where it comes in at, -and check lift on each valve.

Good thought, Brent. I know the timing gears are meshed correctly according to the marks but who says the cam was reground correctly or that is was reground at all and therefore worn as Katy says.
Jim B, GM - Holden carb not getting on with a Ford engine, I like that but they work together well on the other engines. I should have said in my original post that all 3 carburettors were completely rebuilt by the same guy so they should all be the same and good.
When I get the oportunity, I will do as Brent suggests, pull the motor and degree it. It'll be a good oportunity to fix that leaky rear main too.
Thanks to all who have taken the time to respond.