Engine running problem

[Dragrace66]

We have an F100 with sbc 350 / 350 combo here, the engine runs at idle, but when we switch the trans into gear the engine stops running. I checked the vacuum lines it looks ok, we changed the trans and converter same problem. If I put the idle at 1500rpm, the car drives but than it is hard to stop the car. If have no idea what parts are in this engine and the builder can't remember, the cr is 9.5:1 and the idle is rough. I think the cam is too hot.
If someone has an idea, please write.

[Hot Rod To Hell]

So does the motor just "stop", or will it just not idle??? If you left foot brake it can you keep it running?

[Rainer]

I told marcus to "cut" the vacuum line to the booster (if he has one) and close this line for more motor vacuum - may be this will help to find out what is wrong -- or something is wrong with the vacuum line to the distributor (or distributor vacuum advance unit itself) -- hmm only ideas

[enjenjo]

sounds like you have a vacuum leak

[12packo94s]

what torque conv. is in the car, and is the motor pretty stock?

[tootallrodder]

Does the engine physically move when you put it into gear? Check to see if you have a loose conncetion which will cause you to loose spark. Had that happen years ago with an GMC HandyVan where you sat next to the engine. I opened the engine compartment lid and watched the whole "Dance" when I saw the loose wire. Just a thought.
Good Luck.

[WildWilly68]

If you are running a pretty hot cam with a stock converter it will do that. I had a 10 inch converter in mine with a 495 lift/ 302 duration cam and it would die in gear at idle. Had to switch to a 2300-2500 stall speed converter and it works fine now.
Bill

[Dragrace66]

The trans and converter are stock. Tomorrow I will check the negative connections. I will check the vacuum on the distributor, all other lines are new and checked. If I get the degree wheel I can check the cam. My buddy is at the point to put the engine out and dissamble to see what is in the engine. But I want to check the other thinks first.

[Unkl Ian]

Can you check the manifold vacuum at idle?

[jonizzle]

another thing to check is the idle mixture screws. a good starting point is 2 1/2 turns out with those mixture screws. another thing would be the timing...sounds like not enough. seems that you are pulling enough vacuum to the distributor and that is why it runs good at 1500. i would definitely check both the timing and mixture along with manifold vacuum. hope that you get things worked out.