1973 360 issues.....help

[olibass1]

Hello,
I need some advice on my set up. I recently purchased a vehicle with a 1973Plymouth 360 motor which has been bored 30 over, has ported heads, and has a Comp 470 lift cam. It also has an Edelbrock 318 Streetmaster intake with a Carter 650 4bbl carb. It seems to have stumbling issues and a slight miss while idling and seems "restricted" on accelreation. Is the streetmaster 318 a proper fit for ported 360 heads? Does anyone know where I can get specs on this manifold including port sizes? I'm afraid the ports are too small and messing with my performance. Any input will be appreciated.

Thanks in advance.

 

[rumblefish360]

Your feeling right about this. The engine should have a RPM/Air-Gap RPM up top.
Your questions are yes, ill small sized ports restricting performance.
The stumblings are a carb issue. (Pumpshot)

 

[olibass1]

Do they make an rpm airgap for a 1973 plymouth 360? I know they make a "performer" model.

 

[rumblefish360]

No, what they make (Edelbrock) are a ;

Performer

Performer RPM

Performer RPM Air-Gap for the small block Chysler engines except for the 64 & 65 273 engines.
Theres also a Magnum version of this intake, of for which you most likely do not have since the engine is presumed a 73.

The 360 engine went from 1971 to 2002 or 03. In 1993 the 360 engine recieved Magnum heads which requires a Magnum intake manifold.

 

[olibass1]

Thanks for the info. When you stated the stumbling was a carb issue, What did you mean by "pumpshot"? Do you think it needs to be adjusted and in what way? Any info on how to go about it? Sorry for all of the questions, I'm just getting into working on my own vehicle and I'm trying to absorb as much as possible.

 

[Cranky]

The pump shot is what happens when you step on the gas....pump squirter or just squirters. Take the air cleaner off and look down into the throats of the carb and open the throttle (engine off) and see if you have a good steady stream of gas as you open the throttle. Stream size and duration can be adjusted. If it just dribbles when you crack open the throttle, you will have a stumble off of idle when driving.

 

[rumblefish360]

olibass, your ARE new to this aint ya. Your going to need to read a few books on things because these things your asking about are absoulte basics and telling you how t do everything from ground up is something few are willing to start nevermind finish.

Get a few carb books.