Carb choice for 350

[piecesparts]

[QUOTE=slugish;2393011]

Originally Posted by piecesparts

Ithink you are right on the money peicesparts with your carb knowledge . I have a mildly built 400 with a holly 650 doble pumper. In your opion , is this agood choice. Also having continued problems fouling plugs. Take out & they smell of gas with black sooty tips. Person that built engine thinks by pumping the gas to get it started (no choke ) maybe gas fouling the plugs. Have put new hot plugs in now & keeping an eye on , & not pumping as hard when trying to start . Any feedback would be great .

The 650 Holley Double pumper is a good choice--all manufacuteres make a quality product--Holley is in there, also. I have been to their factory and they are great people to work with. However over the years each individual found things that one brand or another had to take issue with--Holley had the problem of leaking and also the diaphragm breaking issues, but it's reputation is solid. Now for your discussion on the choke--if you have to pump the thing when starting --EVEN on a normal day then I would bet the choke is NOT the issue. A carb does not need choking at ALL times and the gas fouling is probably due to two things 1) leakby in the carb, or 2) overjetting of the carb. Where does your engine run it's best (at what RPM). If it is a poor sl;oppy performer on the city street, then you are probably over fueling.


A couple of questions that are kind of outside the discussion---1) What cam design are you running? 2) Does your truck pull at a stoplight, while you are sitting waiting for it to change? REASON for questions---If you put in a cam that is rather healthy, then your truck is probably working itself against the torque convertor and tranny (I am guessing you have an automatic--I may be wrong). This bad idle and the torque convertor lends to loading up your engine with raw gas (due to having to set the idle high on the carb to overcome the bad idle conditions). This is primarily due to the idle adjustment is NO LONGER in the idle circuit on the carb ---it is now in the transition area. If so, then a change to your torque convertor's STALL is necessary to get your idle screws back where they belong (JUST A GUESS). I had to take my stroker motor's tranny to a 2400 stall to get a better run and idle response. The change was tremendous.