Been emailing holleys tech support about my quick fuel carb. It's a Slayer 600 vac secondary. Mild cam, 360 28th 2.02 valves headers, RPM intake etc. Ever since new, my idle mixture screws have made the most vacuum and idled best when turned half turn out.still smells rich. If I back them out more vacuum and idle drop. Talked to holley, they said definitely go up a couple sizes on the idle air bleeds which I kinda figured anyway. This carb has a 2 corner idle adjustment, but they insist I have to change the secondary idle bleeds as well. What do you carb experts think? Summit is out of stock on the secondary bleeds but I went up to a 72 instead of a 70 on the primary side. Will just changing the primaries be enough or do I need to find bigger idle bleed for secondaries too?
Quick fuel air bleeds
- Thread starter Dartish
- Start date
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I've been dealing with the same carb and curb idle adjustments at 1.5 turns out A/F(running rich). I started changing air bleeds both primary and secondary with little success. I'm having better luck going to smaller IFR's idle fuel restrictions on the metering block. I went from whatever the stock restrictions where down to .029 then down to .025 and i may end up with .020 to get it just right. I want to achieve about 1.5 turns on A/f adjustment currently I'm at 3/4 out from seated position. Also, if you haven't adjust your transfer slot to .020 you may need to do that first. I'm doing this by a 4 step process of tuning. Not necessarily in order of best vacuum reading, timing, a/f ratio, and seat of the pants.
What are you running for engine combo? Carbs worked good since new, out of the box it was 10x better then the edelbrock it replaced. Jetting seems real close. So far I've replaced the stock power valve with a 8.5. Made a huge difference. But I'm pulling 18" vacuum at 600 rpm. T slots are almost perfectly square. Just getting tired of the rich idle.
360 comp cam .454 lift. 19" vacuum I also put a 8.5PV in I haven't been messing with my carb lately but I am going to try one more adjustment to .020 on the IFR's. I went from burning your eyes rich to not much smell of gas now just trying to get it spot on. What i found with just changing the air bleeds was that i was still rich at idle and going lean every where else. The Idle circuit is more so T-slot, a/f screws, and IFR's . I also tried going from a 68main jet to a 66 but that caused me to run lean at 1/4 to 1/2 throttle so the 68 is going back in when i do the restrictions again. .020 IFR is hopefully the last time I have to change it.
Make sure your initial timing is squared away. Mild cam is vague. If it has more than 215 @ .050, my thought is the engine should have 15+ idle timing.
yellow rose
Overnight Sensation
skizzo
Fubar Emeritus II
That. Way small. Not right even a little. You shouldn't be eye stinging rich ootb with those carbs.
Are y'all positive your pv's are closing? Dribbling boosters, sticky butterflies,, etc? And as has been mentioned, timing.
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