Holley 4 corner idle questions?

So what is the best way to set the idle mix on one of thease things? Do you turn them all just a little at a time the same amount or one at a time till you get the best vaccume?

Also what would be a good baseline to start at?

turn them all a little at the time til highest vaccum.
1,5-2 turn should get you close otherwise an idle airbleed change may be nessesary. aldough that will offset the part throttle so a change in idle feed restrictors may be in order and that offsets the main system so a change in main air bleeds may need to get done.... AND the whole circus is on.

EFI???

You will want all four corners turned out the same amount as long as your IAB's/IFR's are the same size.
You will want to hook up a vacuum gage to the carb to read the manifold vacuum.
(Note: Before I start, I like to take a permanent marker and mark each metering screw at the 12:00 o'clock position when they are bottomed out (Clockwise), for my own reference. This is how I can tell if they are all even once I am done tuning.)
Depending on a few things, maybe start out with them all at 1-1/2 turns out. Then get the motor to operating temp and idling at the rpm of your choice. (Note: Once you pick this rpm, always use it during the tuning so you have a reference point for your vacuum readings. You want the highest vacuum reading at this rpm while in N.) Next you will want to reference your vacuum reading and then pick one of the metering screws and turn it in or out 1/8 turn. Then you want to wait 10 seconds or so and reference your vacuum reading again. If the vacuum reading went up, then do the same thing to the next metering screw. If the vacuum reading got worse, then turn it back to the 1-1/2 turn out and then go the opposite way 1/8 turn. Once you get the first metering screw adjusted in or out to make your vacuum reading go up, then move to the next meteirng screw and turn it the same direction as the first meteirng screw.
- You will want to wait about 10-20 seconds or so after you turn the MS before you reference your new vacuum reading.
- You may have to readjust your idle rpms after the 20 seconds is up because as your vacuum reading goes up, so will your idle rpms.
On your first tuning, you may want to go around the carb 2-3 times and adjust each of the four metering screws and once you start getting closer to your best vacuum reading, you will be adjusting your metering screws less and less each time. This does take 10-15 minutes but if you are patient enough to do this, your idle quality will increase. If this is an auto car, then you will want to apply the emergency brake and put the car in D. Then readjust the four meteirng screws 1 or two more times to now gain the highest vacuum reading at your desired in gear idle rpms. With an auto car, this is more important than tuning your metering screws in N for a "street driven" car. Once you have your in gear idle rpms where you want them with the most vacuum at that rpms, then reference where the marks are that you made on the metering screws. They should all be real close to the same amount of turns outward. Once the outside temps go up or down, you will want to retune your metering screws in the same manner.
The first time you tune the carb will take the longest because you have to get it close in N and then fine tune it in gear.
Once you are done and you still do not have the idle quality that you want, try adding more initial timing and then retune the carb again.

OK so now it iles fine but it runs like crap every where else in the RPM range.

I put 84 jets all the way around and 6.5 PVs and don't know what else to try. It has #37 squirters.

The motor is a 360 with ported magnum heads 9.0 actual measured compresion ratio. Comp XE268 cam 1.6 rockers TTI headers 2.25 dual ex no muffs and it does have a crossover pipe. M1 single plane intake.

what carb?

80509 830 CFM double pumper.

I just tried some 31 squirters in it and it won't rev at all so I pt the 37 back in.

The problem is holding at a steady RPM it breaks up real bad and smells rich (my trunk is not sealed great right now so I can smell whats going on a little ).

are you positive your timing is not at fault here? anyways,
did you check the powervalves?

I tested both power valves and they are good, and timing is 18* initial and 33* total. Those settings worked perfect with the 770 vac secondary I had on a few minutes ago.

fuel bowl level? fuel is making an unwelcomed entrance somewhere.

Fuel is just touching the bottom of the sight glass

What was the vac reading in gear at idle

11 inches

Quote:

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I tested both power valves and they are good, and timing is 18* initial and 33* total. Those settings worked perfect with the 770 vac secondary I had on a few minutes ago.

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Timing looks ok. How much of the transition slots are showing? Any more than about .020" and you will be in to them.