Okay everything is new and it has been running fine. The engine has had a complete breakin. Here is what i have.

289 hyper pistons
lunati cam
670 street avenger
stealth intake
msd mech ign.

the car has been running perfect since the breakin but today i noticed a flat spot when accelerating. It only does it under load. the rpm doesnt really matter. when i slowly accelerate during a cruising speed it sputters and dogs out. If i floor it it only does this for a moment then it wakes up.
This is a brand new thing.

With the airfilter off i can see the carb pupming fuel when the throttle is opened. i dont think it is the accel. pump. The carb is brand new also. I could not find any vacuum leaks. Could it be the Mechanical advance on the dizzy.

in nuetral it revs just fine.

 

it could the the advanece. hows it idle?

 

My 6cyl sputters for a second and then kicks in when I floor it. Mine does this because the other jet opens up, I have a 2v carb. I run 1v when cruising and then it hits a certain spot and opens up the 2nd valve.

 

initial timing is at 20* and it is idled at 750 rpm. its been smooth since the start and nothing has been changed

 

i am wondering if the carb got clogged

 

could very well be. have you tried cleaning it?

 

could be a fuel pump.

pull the coil wire

pull the fuel line from the carb and place the line in a jar

crank the engine about 5 seconds.. the jar should have a goodly amount of fuel in it....at least over a cup.

However I doubt this is the issue...

Could be an obstructed jet..Do you have a fuel filter....If yes..it could still be an obstructed jet.

Happy hunting.

-Gun

 

20 degrees of initial timing with a 289? Wow, that's high. I can't normally get more than 14 degrees. What is your total advance and at what rpm?

If it is not timing related, look down the carb barrels whileit is idling and make sure you don't see any fuel dripping. Most changes in new set ups are caused by a piece of debrise getting stuck under the needle.

 

Fakesnake

If i recall it is a total of 28* @ 3800 rpm total advance. that would put my timing mark at about 48* while reved up. i set it with the springs and the wieghts that came with the dizzy, i am using the msd mechanical unit.

But like i said it was a sudden thing. everything was great then while driving it started
getting crappy.

I have a pretty agressive cam.

It is the lunati

http://store.summitracing.com/partde...K&autoview=sku

 

Is it easy to take a holley street avenger apart and clean it out. Will i need to get new gaskets. like i said it is new and has only been used for about 2 months