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TR6 TR6-tuning new motor with mods

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Coyote1

Coyote1

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I have a 74 1/2 TR6 which had been partly restored by the PO who died before it was finished. The motor was rebuilt but I have no specs. I know the head was shaved (had to install short push rods). It was most likely bored and may have a cam upgrade but not certain. Cylinder pressure, all 185-193 psi. Everything appears to have been very well done.
It has dual exhaust (no header), Pertronix Ign. and rebuilt Weber DVG carbs w/Carter electric fuel pump. All smog removed.
I have adjusted the carbs and they are within spec. I set the timing to 10 degrees BTDC. Problem is, I cannot seem to get it running smooth. It starts and runs a little rough which gets worse as it warms up.

Given the mods, should it be tuned different from spec.? Am I missing something or do I have a problem?
 
what's your idle RPM? I have reworked the lump a bit in my 75 about the same as yours,head shave,cam, balanced,pertronix, with the stock Strombergs.I run it a bit rich at idle,and Rpm is at 1150-1200 with still a bit of a lump to it.Mashing the go peddle straightens it right out tho
 
It would not hurt to play with the rotation of the distributor once you get the engine to idle. If it smooths out fine, if not, I suspect the mixture may be rich.
 
I have it set at about 900 rpm. It does seem like it is running rich but the idle mixture is where it should be at about 1 1/2 turns. I will try to bump up the idle speed and see.
 
Set the RPM up to 1050 and adjusted the timing to various positions. ended up at 14 degrees BTDC. Smoothed out but idle seems too fast. Once it completely warmed up it began to stutter and die. I've tuned a lot of cars but never ran into this before??? I think you may be right about it being rich but still don't get why it dies.
 
Are you able to immediately restart the engine without a cool down period ?
 
Yes, I can restart it but it remains rough and dies. It seems to be something about getting warmed up. I may try some hotter plugs but I'm beginning to think I may have a problem with the head gasket.
 
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