Holley/Demon Carb stumble
Learned a lot along the way.
Do it this way.
Measure the turns in on the idle mix screw to open the throttle blades enough to reveal .010, 020, .030 and .040"
Do the same for the secondary throttles.
Measure how deep the transfer slots are - primary and secondary. Secondary might start higher up. If so, keep that in mind.
Only drill if you can't get the engine to idle at reasonably civil rpm with primary transfer slots in the 0.20 to .030 range and there's problems coming off idle.
Before drilling, try a opening the secondaries a hair more. That's why measuring beforehand helps a ton. You'll know if you've got to open either side up in the .040 range or more to keep it idling - that's going to be no good.
The restrictions need to be ballpark matched up.
For example, if the IFRs are 0.035 then its unlikely to be a good match with IABs .068
Definately want to know the power valve restrictions before making the jetting decisions.
I assume since you're using a primary block on the secondaries, you will be using a PV plug there. If so - then its just the primary side to be concerned with.
I can tell you what the 3310 blocks were originally - doesn't mean that's what they've got now.
What rpm is middle of 2nd ?
yea. You're not the only one that's found a tighter converter can make lots of work. Took a long while to work everything out.
Learned a lot along the way.
I agree with the others.
Do it this way.
Measure the turns in on the idle mix screw to open the throttle blades enough to reveal .010, 020, .030 and .040"
Do the same for the secondary throttles.
Measure how deep the transfer slots are - primary and secondary. Secondary might start higher up. If so, keep that in mind.
Only drill if you can't get the engine to idle at reasonably civil rpm with primary transfer slots in the 0.20 to .030 range and there's problems coming off idle.
Before drilling, try a opening the secondaries a hair more. That's why measuring beforehand helps a ton. You'll know if you've got to open either side up in the .040 range or more to keep it idling - that's going to be no good.
While you're waiting for stuff, go buy the drill sets so you can measure everything.
The restrictions need to be ballpark matched up.
For example, if the IFRs are 0.035 then its unlikely to be a good match with IABs .068
Definately want to know the power valve restrictions before making the jetting decisions.
I assume since you're using a primary block on the secondaries, you will be using a PV plug there. If so - then its just the primary side to be concerned with.
I can tell you what the 3310 blocks were originally - doesn't mean that's what they've got now.