Hey all, I am having some issues getting my 350 to run right. I am running a 350 bored.030 over with stockish flat top pistons, an XE 258 cam, World products Sprtsman II heads, an Edelbrock Performer manifold, and a 600CFM vac secondary Holley. My issues are:

1. sporadic idle. Idle is not stable. Surges if you will.

2. Off idle hesitation

3. Backfires through carb on sudden acceleration.

4. Fuel line pulses at idle. Very noticeable.

5. Runs like a dead ape

I have set the fuel level 1/8" below the fuel bowl. I set the timing to 10* BTDC. The dizzy is your standard HEI with the second lightest springs on the mechanical advance. Vac advance is connected to a ported connection.

Plugs, wires, cap and rotor are new. Replaced them all today with accel pieces. Ummmm HELP! Thanks!!!!

Bill

 

I`m lucky enough to have friends in the hobby.If you can try to
borrow another carb and distributer to try out.

 

Have you checked for a large vacuum leak or flooding?

 

I have checked for a vacuum leak and can not locate one. I can cover the carb intake and it dies right out. The motor ran great until I let it sit for 6 months. I am thinking I may need to rebuild the ol' Holley.

 

I don`t know what your goals are,but this could be a good excuse to upgrade to a performer RPM air gap,a 650dp
and a larger cam to help take advantage of those heads.

 

Have you tried a higher timing - say 12-14? My 350 swap I had to go about 13*BTDC. I got it to run OK at 10, but then I didn't have enough vacuum for the brakes, and readjusted to 13 - got plenty of vacuum and it ran so much better.

 

So I made some progress today. I rebuilt the holley last night and put 68 jets in the primaries. Changed the cap, rotor, plugs, and wires and upgraded to the accel super coil. Set the timing at 14* and took her fo a spin. HOLY COW!!! what a difference! I still need to tune a little more as I have a little hesitation from a roll ifI nail it. But MUCH healthier. I will keep you posted.

As a side note, be carefull when you red the jet size in the holley kit. You wouldnt want to say put a 98 jet in instead of a 68. Just FYI....