340
Mopar Lover
Joined: Nov 2007
Posts: 2,424
Likes: 248
In my experience (I had a 360, now a 318 while building a mild 360) YES you need a spacer. This "new alcoholized" gas seems to be very bad for vapor lock, fuel boiling in the carb bowls and related problems I conversed with someone on one of the forums who had done everything he could think of, but STILL HAD fuel boil in the carb bowl on shutdown on a hot day. (Edelbrock carb) In this respect the Holly 4150 style 4bbls might be somewhat better, as the bowls are "up" and get a little airflow around them.
The things I did with my (67) Dart helped the problem immensely.
1--Future--When I assemble the "new" 360 I WILL block the intake head crossover
2--I have an isolator gasket, I think about 3/8 or 1/2 plus a thin gasket and plate to adapt the pattern from spread to square bore
3--I finally went to a rear mount electric pump, and got rid of the mechanical pump
4--I added a return line to the tank, and built a vapor return system. The key to this is fuel filters with the orifice built in. The Wix numbers are 33040 (5/16), or 33041 (3/8) or a 33054 which has an angled return port
These filters can be mounted vertically or horizontally, but the 1/4" return port must be up
The things I did with my (67) Dart helped the problem immensely.
1--Future--When I assemble the "new" 360 I WILL block the intake head crossover
2--I have an isolator gasket, I think about 3/8 or 1/2 plus a thin gasket and plate to adapt the pattern from spread to square bore
3--I finally went to a rear mount electric pump, and got rid of the mechanical pump
4--I added a return line to the tank, and built a vapor return system. The key to this is fuel filters with the orifice built in. The Wix numbers are 33040 (5/16), or 33041 (3/8) or a 33054 which has an angled return port
These filters can be mounted vertically or horizontally, but the 1/4" return port must be up
Mopar Lover
Joined: May 2012
Posts: 1,380
Likes: 103
From: Debary Florida
it was probably me i just posted another reply
its the fuel alright i don't use hollies any more even though i used them trouble free since the 80 s
as soon as the fuel had 10 % alcohol added to it ,,in some places they have found 30 % my hollies started failing first the power valves would start to leak maybe last 3 months if even that the accelerator pumps maybe 6 but the big thing i noticed when i would pull them apart was that all the gaskets where soaked with fuel and wat should have been dry was wet i would get puddling at the base of the manifold and the bottom of the carb was wet even after i would rebuild them with special gasket sets for alcohol would only last for 3 or 4 month maybe the guy at the speed shop says every one is have the same problems
since my last 318 project i now use edel avs with a air gap manifold and don't have the leaks just the boil offs and until shes cooled off to running temp after heat soaking she runs rich the price we pay now for using carbs and for fuel injection its still to pricy for me to justify the investment
its the fuel alright i don't use hollies any more even though i used them trouble free since the 80 s
as soon as the fuel had 10 % alcohol added to it ,,in some places they have found 30 % my hollies started failing first the power valves would start to leak maybe last 3 months if even that the accelerator pumps maybe 6 but the big thing i noticed when i would pull them apart was that all the gaskets where soaked with fuel and wat should have been dry was wet i would get puddling at the base of the manifold and the bottom of the carb was wet even after i would rebuild them with special gasket sets for alcohol would only last for 3 or 4 month maybe the guy at the speed shop says every one is have the same problems
since my last 318 project i now use edel avs with a air gap manifold and don't have the leaks just the boil offs and until shes cooled off to running temp after heat soaking she runs rich the price we pay now for using carbs and for fuel injection its still to pricy for me to justify the investment
