Hey guys,
What are the possible causes of hesitation when you go from part throttle/idle to wide open?
I had this problem in the past, replaced my old Holley with a new Edelbrock and my car still never "Kicks In" when I slam on the gas. Doesn't matter if it has run for 10 min or and hour.

It transitions from idle to part throttle fine, but pauses, then accelerates slowly when trying to go WOT..

The only thing that I did not change in my engine overhaul was the PCV valve, everything else in this car is new.

Thanks

 

Have you checked the timing? Is the distributor new also? Is the vacuum advance working?

 

Its a brand new MSD Street Fire HEI, I have the timing set at 6 degree BTDC, when I rev it up I can see it climb to about 8 - 10 Degrees BTDC.

The vacuum advance hose is hooked up on the passenger side of the carb, which edelbrock said was the "timed side".

I did notice in the manual they say higher lift cams (which I have on my 350) use more vacuum so you may need to connect the distributers vacuum advance directly to the manifold.

I haven't tried this yet, but it just doesn't seem like it should be so bogged down during that transition to WOT that it feels like it DIES for a 1/2 second.

I think the MSD vacuum advance can also be manually adjusted with a allen wrench, and they also provided a timing advance stop plate, but I haven't put it on yet.

Hopefully that provides some insight.

Thanks

 

Any ideas guys?

 

What size and type of carb is the Eddy? Is it vacuum secondaries? I had a similar problem with a Edelbroke on my 427. Just didn't perform well on WOT, and I tried everything on Eddy's list with no luck. Finally went to a Holley 750 with vacuum secondaries and it came alive!
I'm guessing the secondaries are either opening too soon, or it's jetted too lean. Might try the larger jets, and see if that helps. You should also change the vacuum to the full vacuum to see if it helps.

 

Here is the manifold/carb combo I bought from summit:
http://www.summitracing.com/parts/EDL-20214/

I did notice in the manual it says "slightly radical cams (I guess they mean bigger than normal)" could use more vacuum and it may be necessary to hook the vacuum advance directly to the manifold.

I took a vacuum gauge today and hooked it up to a "t" fitting on the back of my manifold and read 17" Hg @ 850 RPM.

When I revved the engine up with the throttle linkage, the vacuum dropped way down, to like 5" Hg.

Could this suggest there is not enough vacuum for the distributor at a high RPM?

 

You don't need more vacuum at high rpm because by the mechanical advance is doing it's thing by then. They all drop significantly when revved, regardless of cam. You might want to check your mechanical weights in the dist. to ensure they're free and allowing full advance under off idle rpm's.
Check Edelbrock's tuning tips once you've determined the dist. is OK and you've moved the vacuum line to the right side full vacuum.