holley gurus?

[ma67cpe]

I just put a different motor in my car and it has been in for about a month now. While it was cold outside the car ran great. Now all of the sudden the car will not idle. I checked my floats and both were up to high so I have them just below the site plug and was able to run the car with the screw out and gas stayed in. If I turn the idle up it will stay on but as soon as I drop it down to were it needs to be the car dies. I have a holley 4 barrel carb with a edelbrock intake and a pretty good size cam if any of that matters. Thanks for any help or info.

[Baron Von Crowder]

intake leak? Spray your brake cleaner...you know the rest.

[greenbullitt]

with the ethanol in todays gas, the tuneup will never stay consistent. this could be the start of your problem, but there may be alot more to it.

[turbos66coupe]

First makeing big adjustments in idle speed with the "idle" screw is a big no no. You need to adjust idle with idle air screws on the metering blocks. Turn the carb over and set the transfer slots to about .020" gap. Transfer slots are the little slots that run verticle to throttle plates in the carb bores. You should be able to see about .020 of the slot with the throttle blade closed. This alows the idle cicuit to work properly. Set thoose and turn the screws on the metering blocks out 1.5 turns from stop.

What size is the carb and what jets are in it. Try above stuff first if it runs then you need to fine tune it with the screw on the metering blocks. Get a vacume gauge it will help

I use a vacume gauge and with the car running I turn each mixture screw an 1/8 of a turn until I get the highest vacume reading. Once vacume won't go up. I go back an 1/8 of a turn and then lower the curb idle screw until you get the desired rpm.

[turbostang]

First makeing big adjustments in idle speed with the "idle" screw is a big no no. You need to adjust idle with idle air screws on the metering blocks. Turn the carb over and set the transfer slots to about .020" gap. Transfer slots are the little slots that run verticle to throttle plates in the carb bores. You should be able to see about .020 of the slot with the throttle blade closed. This alows the idle cicuit to work properly. Set thoose and turn the screws on the metering blocks out 1.5 turns from stop.

What size is the carb and what jets are in it. Try above stuff first if it runs then you need to fine tune it with the screw on the metering blocks. Get a vacume gauge it will help

I use a vacume gauge and with the car running I turn each mixture screw an 1/8 of a turn until I get the highest vacume reading. Once vacume won't go up. I go back an 1/8 of a turn and then lower the curb idle screw until you get the desired rpm.

This is correct. However, the jetting has no effect on idling - if it does, there's some other problem.

If the car is now dying, you're most likely experiencing a ruptured power valve or a bad needle and seat. They'll both dribble fuel through the boosters and flood the engine.

If it's having a problem idling lean enough, you can adjust the secondary throttle blades to lean it out (they don't have the transfer slots in most cases)....but most likely, this is not needed on your car.

[Diabolic]

Here is how I have always done mine in the past.

Turn the Air/Idle srews on both sides in all the way and back out each 1.5 turns.

Start the car and bring the idle speed to 800ish

Begin turning one of the ide/air screws counter clockwise and watch a vacume guage. Back it off until the highest vacume reading is obtained. Now go do the other side the exact same way.

Turn each of the idle/air screw in 1/8 turn clockwise from that point.

Take note of the vaccume reading. Lets say it's 14". Now divide that number in half and add .5, soooooo 14/2+.5=7.5. Now purchase a 7.5 powervalve and install it in the front metering block.

This should get the carb setting 90% to ideal. The rest is fine tuning. You may need to drill small holes in each of the primary butterflies to allow enough air get past the blades at ide. If you try to accomplish this by turning the idle screw too much, you will go past the idle transfer slots and lose control of your idle.

[80coupe]

im having problems with mine also not a idle just when your driving it seem like it comes in right about 1500-2000rpm. Its only on first hit of the throttle im lost about to just go buy a new one. it will run all day long just when you first get going!

[turbos66coupe]

This is correct. However, the jetting has no effect on idling - if it does, there's some other problem.

If the car is now dying, you're most likely experiencing a ruptured power valve or a bad needle and seat. They'll both dribble fuel through the boosters and flood the engine.

If it's having a problem idling lean enough, you can adjust the secondary throttle blades to lean it out (they don't have the transfer slots in most cases)....but most likely, this is not needed on your car.

most deffinetly agree with that. i was just curious if he has ever gone that far in tunning it or if he had any idea what was in it. info for futher tuning

[ma67cpe]

most deffinetly agree with that. i was just curious if he has ever gone that far in tunning it or if he had any idea what was in it. info for futher tuning

I have never gone that far in tuning a carb. This is my first four barrel carb. I just bought a stock rebuild kit before I put it on.

[ma67cpe]

Here is how I have always done mine in the past.

Turn the Air/Idle srews on both sides in all the way and back out each 1.5 turns.

Start the car and bring the idle speed to 800ish

Begin turning one of the ide/air screws counter clockwise and watch a vacume guage. Back it off until the highest vacume reading is obtained. Now go do the other side the exact same way.

Turn each of the idle/air screw in 1/8 turn clockwise from that point.

Take note of the vaccume reading. Lets say it's 14". Now divide that number in half and add .5, soooooo 14/2+.5=7.5. Now purchase a 7.5 powervalve and install it in the front metering block.

This should get the carb setting 90% to ideal. The rest is fine tuning. You may need to drill small holes in each of the primary butterflies to allow enough air get past the blades at ide. If you try to accomplish this by turning the idle screw too much, you will go past the idle transfer slots and lose control of your idle.

I did the screws just like that and I have to go way higher than 800 to get it to idle. I dont have a tach but if I was to guess I would say it will only idle at 2500 to 3500

[ma67cpe]

I just found this when I typed holley 1850 tuning

Because the 1850 is designed with a somewhat lean idle circuit, driveability problems occur when it is used on an engine with a big camshaft and low manifold vacuum because the idle circuit cannot supply sufficient fuel to run at light throttle.

[Pooter]

I just found this when I typed holley 1850 tuning

Because the 1850 is designed with a somewhat lean idle circuit, driveability problems occur when it is used on an engine with a big camshaft and low manifold vacuum because the idle circuit cannot supply sufficient fuel to run at light throttle.

Thats still weird that it idled/ran fine when it was colder though? I would think it would have been more difficult to idle when it was colder compared to the warmer temps weve had recently...

[46Tbird]

I'm going to guess that you have some trash in the needle/seat on the primaries. I've found that the replacements they supply in the rebuild kits are extremely sensitive to trash. Pull it out, blow it out, reinstall, and reset your float. Even if it doesn't work, at least it's free.

[ma67cpe]

I'm going to guess that you have some trash in the needle/seat on the primaries. I've found that the replacements they supply in the rebuild kits are extremely sensitive to trash. Pull it out, blow it out, reinstall, and reset your float. Even if it doesn't work, at least it's free.

If I am able to adjust the float level wouldnt that mean that they are working correctly?

[Diabolic]

I did the screws just like that and I have to go way higher than 800 to get it to idle. I dont have a tach but if I was to guess I would say it will only idle at 2500 to 3500

You have bigger problems. Internal fuel leak perhaps and the only way it will run is when you crack the throttle blades a ton to introduce a lot of air to lean it out to where it will run. Leaking powervalve most likely. Ever get a carb backfire?