I have a holley street avenger on my 383 and it was prety close from the factory. It is a bit rich but not to bad. I need a hand getting it spot on though. My real challenge is timing. I have the base time at 12 degrees...I know that seems like alot but it will not run below 10 degrees. It just dies. When I huck the vac advance up to the bottom vac line on the carb (all the way down on the bottom on the front passenger side) the timing jumps to 35 degrees I am new to the vac advance thing so I need some help. Any suggestions

 

Isn't there a vac connection up a little higher on the carb ...I think that's where you attach the dist. vacuum.

 

I am not sure but there is a vac port just above that one.

 

The Timed vacuum port for the distributor should be on the passenger side above the idle mixture screw on the metering block. It sounds like your attaching the vacuum line to manifold vacuum.

Setting the idle, what worked for me was decreasing the timing and increasing the idle while using a vacuum gauge to adjust the mixture screws.

Check out page 6.
instructions

 

well you see, ill hook my laptop with EFI Live to your carb and to your dist. and we can tell it what to do.. HAHAHHA,, sorry,,
Im goin to make a Point Presentation like what we talked about at Obys...
i know your truck sure sounds good!!
have you tried to call MSD and see what they said??

 

No I havent THey would just send me more instructions that I would have to ignore

 

Back in the days GM hooked there big block cammed engines to manifold vac to hide the cam and make it idle better after all no matter what port you put it on it will be 0 vac at WOT, I use to curve distributors all the time back in the good old 70's