Initial Timing Advice

[Ricko1966]

Bah! e.t. wins drag races!

It's easier to use mph to set timing, fewer variables,like human error on the stop watch etc.etc. Best mph will equal best E.T. also.

 

[Rusty Nail]

I'm just yankin your chain Ricko

 

[rich weyand]

I think you got to the right place. Here's all the whys and wherefores.
https://www.gmsquarebody.com/threads/ignition-timing-for-first-generation-gm-v-8-engines.14508/

 

[Matt69olds]

@Ricko1966 You’re the man. No pinging and temp gauge was good to go. I can’t thank you enough. I was literally thinking about selling the truck after all the nonsense after changing the flywheel, manifold and carb. It’s crazy how a bunch of small things can wreak havoc. The old vacuum gauge was like a straw sucking in air. What an over all change. Again, thank you, so much and have a Happy New Year.

This is a classic example of what happens when people modify things and get frustrated if the desired results aren’t as expected.

Rarely does a performance upgrade work perfectly without needing some other change. Exhaust upgrades might improve the performance, but big improvements in breathing might require some additional fuel to really make the engine happy. Ignition timing needs to be correct, if you change the way the engine breaths obviously the ignition curve won’t be optimal for when the engine was choked off.

It really doesn’t take all that much effort to dial things in. Glad to hear the op took the initiative to figure it out. There are to many people perfectly content driving with engines that clearly don’t run right.

Either take the time to do it right or leave the hood closed and the engine stock

 

[Squirrely Brother]

@Matt69old Typically, I’d agree with you. Not the case here. This is what happens when I let someone else work on my vehicle, because I was trying to make nice with my daughter’s boyfriend who’s a GM Master Technician who’s all buffed out like a turkey saying he can do the work better. I’ll stick to doing work myself. It gets done right, cost less and takes less time in the long run. I’m gracious for being taught how to dial in total timing on a carb vehicle, because it’s a heck of a lot easier to make a change on the computer for the ls7.

 

[Squirrely Brother]

Something didn’t work. Stuck in a parking lot. Choke light came on, rpm dropped and can’t get it started. Ran good for 20 miles or so.

 

[Ricko1966]

Do you have spark?Do you have accelerator pump shot?

 

[Squirrely Brother]

Just checked there’s spark and the throttle squirts. It started after multiple attempts then stumbled and stalled.

 

[semperfiguy98]

Just a shot in the dark.. Did a vacuum line fall off somewhere, or get burned by exhaust? Is the distributor hold down tight?

 

[Squirrely Brother]

Just checked vacuum lines are all plugged in and intact and distributor is tight.

 

[Squirrely Brother]

I leaned the electric choke back to 3 from middle and it started right away and drove home like nothing happened. Can the choke being too fat cause this? I tested the coil with a multimeter and all was good. Could it be a faulty coil? I have no f-ing idea. It’s weird.

 

[Ricko1966]

Get the coke fully open A.S.A.P without causing drivability problems, and don't set it shut tight.Set it against an 1/8 inch drill bit. Then tweek from there.Make sure you have 12v with engine running to choke and a good ground to choke

 

[Squirrely Brother]

I stand corrected. I said backwards. In the parking lot I moved the choke clockwise 3 notches from center, which made it fatter which opened the plate/flap the thickness of 2 maybe 3 credit cards. I’ll measure with a bit.

 

[Ricko1966]

Another thing a lot people do not realize is if you set your idle speed usIng the throttle stop screw, instead of the idle adjustment screws, is many times you uncover the transition ports in the carburetor which screws up your fuel delivery at low end.
Not saying you can't tweak it a little but there's a fine line between a little and too much. Turn a carburetor over some time and familierize yourself with the visible ports and passages.

Rusty, you didn't ruffle my feathers, I just didn't know if you knew. How many people do you think will get tickets this week tweeking their timing?

 

[Rusty Nail]

I think you got to the right place. Here's all the whys and wherefores.
https://www.gmsquarebody.com/threads/ignition-timing-for-first-generation-gm-v-8-engines.14508/

Lookit who's been lurkin! - Merry Christmas Rich!