Need engine help!!!

Ok just got a side job on a 67 Camaro. The engine is a Dynoed 383 stroker. It has been sitting for 5 years in a body shop and has not run. So I get it running and times 14 deg of inital timing runs great ands drives great then I pull in and park and it will diesel and switch directions for a few revolutions then stop. I went from 6 to 16 degre of timing but could the carb cause this diesel problem?? I pulling my hair out!!! Please help

Dieseling can be caused by any number or combination of things, but most commonly are caused by one or both of the following two reasons:

1. High idle RPM.
2. A hot engine.

Other sources could be lean mixture, vacuum leaks, too much compression for the octane rating of the gasoline you're running, excessive static timing (you mentioned you timed it to 14 degrees, you should run it no more than 8), heat range of spark plugs too high, a lot of 'squeeze' or quench in the cylinder combustion chamber, valves with no margin or sharp edges, carbon buildup, exhaust restrictions, things along those lines.

A radiator that does not have the proper cooling capacity can 'enhance' an engine's will to diesel. Make sure your cooling system can handle the 383.

FWIW, the engine in my car has a high degree of designed in quench - the flat portion of the combustion chamer (level with the deck surface), and a reverse-dome piston design, which causes the air-fuel mix to forcefully squeeze out of the area on the piston upstroke. This causes a better mix, but can contribute to a dieseling situation (and does on my car - has for 300,000 miles now). It most often happens during the summer when it's hot outside, so my workaround for the last 15 years with this engine is to turn it off with the transmission in gear.

Thanks for the reply! I have the speck sheet from when it was dynoed from the engine builder and the timing was 6 for initial 25 total and 31 at 3800 RPM. So I started out at 6 on initial and ran ok but it ran best at 14. I tried it at 6,8,10,12,14,16 and it ran great at 14 for initial. I am kinda thinking it is on the lean side due to when I wipe my finger in the tail pipes it just very little black. I sprayed the base plate and intake for vac leak but no RPM increase so I don't think there is a vac leak. It does have a Demon Carb on it a Speed demon. Same carb used on the dyno. I keep going back to the dyno sheet because the motor is still fresh just been sitting. I set the idle mix screws 4 of them on Demon 1.5 turns out to start and watch the vac guage but I always turn in to get RPM increase and a good idle. It ends up I turn in like .5 to 1 turn in so I am afraid it too lean. I have the hood off when I am running this car as the owner does not want it scratched. It runs at 195-199 on the road for temp with hood off as I know the hood will help. WHen its idled back in the garage it will hit 210 then shut off and diesel. The Rad is a big high dollar nas car Rad and is bigger than any 4 core I have seen with 2 electric fans. So I think it ok for cooling. Is there something I am doing wrong with timing and carb?How do I ritchen up and keep it running good and put the timing?

I don't think mixture is your problem, to be serious. You're not going to have soot in the tailpipe unless the mixture is extremely rich or the engine burns oil (which could happen on a fresh engine until it's broken in).

My spider senses tell me that the dyno man knows best what this engine could do, so follow his advice and set the static timing for 6 degrees BTC. These guys dyno for the best performance and then write down the proper specs for that performance. They don't do one run and call it quits.

You may have a higher RPM engine at idle with the timing more advanced, but your higher RPM power will be diminished and you could well experience potentially fatal (for the engine) detonation. I assume it's running the same distributor now as on the dyno. If not, get a sprnig and weight kit for the distributor and set the spark curve to match the specs above.

As far as the 4 mixture screws=These are for adjusting the IDLE circuit only and have no effect on the OFF IDLE, MID RANGE and POWER circuits.

Still haven't told us what compression ratio and what fuel octane?

Also what distributor?

Whenever you adjust the timing you also have to readjust the idle rpm's.

I would think idle rpm's should be around 700-800.

Also need to look for other sources of vacuum leaks. PCV valve, brake booster, tranny modulator, etc.