Technical Flathead timing issue...(Carbs, And Timing).

Moving along on my 30 AV8. Going through each section of the car until I correct and/or check all of the PO's work. I finally got to the point where I can address the Carb issue. The PO had put some sort of progressive set up on it and then abandoned that plan when he couldn't get it to work right and then he half assed blocked of the rear carb.
I had worked on that getting it to run OK knowing that I would be switching to straight linkage and that I was only going to be driving the car around town on short trips.
Well I go the carbs rebuilt and the linkage sorted out and fired it up, adjusted the idle etc and took it for a ride...Wow, that really woke the old girl up, much snappier and responsive.
however, It would start to fall on its face at about 3000rpm, a heavy misfire almost like a rev limiter. then when I let off and clutch to shift I get a big ol' backfire out of the exhaust. Happens in all gears, all speeds...
While I am concentrating on the tach and listening to the engine I took my eyes off the temp gauge for a few min and when I finally look over it is hot. 230-240 on the right side and 220 on the left.
I get it home and hook up the timing light. The only "mark" I see is about 1.5 inches before the pointer at idle (~500rpm)
The engine is a '51 truck block, EAB heads, Edmunds 2x2 intake, holley 94's fresh rebuild, isky max-1 cam, 4"merc crank and Mallory dual point with pertronix and no vac advance (built by bubbas)

My question is: With that engine set up is there any good reason the timing would be so advanced at idle? I am assuming it is falling on its face at 3000 because it is out of advance.

i am going to dial the advance back to the pointer at idle and see what i get (unless someone can give a good reason not to dial it back to the pointer.)

thanks for the input.
Chappy

 

Update:
I got the timing pulled back close to the pointer but... I am pretty much out of adjustment on the dizzy to the point that I cant get the hold down back on. See pics

What gives??? Anyone seen anything like this before?
Anyone know approximately how far off the pointer the timing mark should be at idle with this type of dizzy?
Thanks.
Chappy

 

dizzy is a tooth off

 

I was afraid that would be the answer.

So if I have my direction right I need to move the dizzy shaft one tooth counter clockwise as I am looking down at the top of it?
Thanks for the input
Chappy

 

Yup , move er a tooth or two .GgRrrr ,done it myself .

 

at idle pointer should be at mark on pulley 4deg btdc and dist should have no more than 22deg advance in it for 26 total........

 

carbs should be set with a Uni-Syn before any other adjustments

 

Thanks for the info guys,
This is my first flathead. I have done a distributor replacement and move on a number of SBC but never on a Flatty,
Is there anything I need to be aware of? Pitfalls, shortcuts, tricks, etc or is it a simple mark it, lift it, turn it, and slide it back into position?
I have been trying to do some research on this and haven't come up with much in the way of instructions.
I just want to make sure I am turning in the right direction and that I am not missing something like an oil pump drive alignment or similar.
As always, any advice would be greatly appreciated.
thanks
Chappy

 

Getting the carbs sorted is what led me to uncover this timing issue... once the carbs were balanced and both working properly I started having/noticing the stumble at 3000rpm/back fire/temp issues. Which lead me to find the timing was way off at idle...

 

It's easy. I had mine off a tooth, car ran but not too good. Just pulled it out and stuck it back in a tooth CCW in my case.