Dual carbs not working correct! Please try to help!

[wolffcub]

Ok i thought I would start a new topic for the issue I am having and not tuck it in with my other generic truck thread here. Thought this might get more replies.

My scenario is this.
Just recently got the truck on the road after 15 years of tinkering. Have a 1955 inline 235 that was fully rebuilt. Cam is still stock grind. Installed fenton split headers, dual Edebrock intake, dual 32 DFT carbs from Tom Langton, Pertronix ignition. The truck runs, it idles smooth in my opinion and runs only fair when driving around. It seems like something is lacking after hearing so may praise and talk about how good these 6's can be.

I have fully and properly set up the engine to my knowledge prior to getting it on the road about 2 weeks ago.

- Found TDC on #1 (yes I mm sure its not 180 out) Confirmed rotor position and valve positions.
- Set the octane selector to 0
- Started engine and set timing to stock setting using the ball bearing in flywheel.
- Got to running temps.
- Used vac gauge on intake manifold and found the needle jumping around so I rechecked my valves and found that some were set wrong. Corrected valve rocker gaps and vac needle was steady like a rock.
- Adjusted timing via the distributor to get best vac reading on gauge with the vac advance unhooked and blocked off at carb. 19 was the best it would do. It took a bit of timing advance to get the vac reading it to that number. Backed off the timing just slightly to get 18 vac reading after by using the octane selector so I can make easy adjustments later.
-Played ever so slightly with the idle mixture screws on the carbs but they were set perfect and the adjustments in either direction only made it run rougher.
- Set the RPM to 500 ish

Been driving it now for 450 miles and i have filled the tank 3 times. This cant be right. Accelerating moderately or aggressively it just slowly climbs, gets a bit more torque around the 2000rpm area and keeps moderately climbing after that. If I carefully let off the pedal as I am accelerating it actually for a brief a second accelerates with power. As if the second it leans out by me not applying and acceleration it stars to accelerate correctly. The smell of gas is so strong after accelerating almost every time I try to get up and go. Every time i also let off the gas and decelerate with it in gear the exhaust sputters and i get slight backfiring and pops.

Well I tested out the truck today with one carb at a time. All I did was disconnect the linkage arm but left it connected to the fuel line. The first try with carb "A" felt the same. Acceleration was slow and there was still a slight popping / backfire sound when letting off the throttle and letting it decelerate in gear. Truck still ran and never starved its self on the single carb like i thought it would.

Switched to carb "B" and the truck ran even smoother than what I thought was set up correctly before. You can't feel the engine running now but you can just hear it it's that smooth. It has sooooo much torque now compared to running both carbs together or just carb "A". When accelerating and getting to the point with the pedal travel that actually opens the secondaries you can feel it take off even more it and it starts to pull even harder!. The way it performs now is more what I was expecting form this inline in the first place.


The strange thing is with just one carb attached and working it should be too undersized in cfm to run the engine by itself but it runs it like it was meant to be. Something still bothers me about both of these carbs even though one works better than the other. It still seems like jetting is off or possibly its something else.

I have yet to call Tom and ask him what he thinks.

Thoughts?