My friend has a dragster with a 568 BBC app. 1000 HP with a 8896-3 1050 dominator that is flooding or black smoke at idle and when you give it 1/2 throttle also. I turned the idle mixture screws in and backed all 4 out 1 turn each. Looked through the venturi and tried to balance the butterflys front and back, each are slightly open, backed the pressure regulator from 9lbs to about 7.5 lbs. Backed the float level through the sight glass to about 3/4 level. After all this it seemed to idle better at about 1300, backed front and back idle adjusters to get rpm to 1150 and it wants to load up and black smoke. During idle i cannot see any fuel coming through the boosters as if the fuel level was high, however, it is rocking and shaking in the dragster as expected. I don''t know much about the history of the carb. except the original carb was swapped for this one as part of the dragster purchase. Just bought it.
What do I need to look for? I have never messed with the 4500 only the 4150's
HELP

float is too high ,set it at bottom of glass with motor at idle,then reset butterfly and four corners.

First off when you closed off the idle mixture screws did it kill the motor? That will tell you if the idle circuit is clean and working.

Does it have adjustable air bleeds?

Bad floats, or N&S need replacing. I would start with a good cleaning, kit, and floats. And the 8896 calibration sucks...

It needs a brand new billet carb from Lightning Carbs. Easy fix!!!



Ok, couldn't help it....had to throw that in there!

OK, lowered the fuel to the bottom of the sight glass, seemed to help but still loading up.
Air bleeds are adjustable.
As I left the shop today I thought about the powervalve...I forgot about this because mine are blocked so I looked on the interned and it looks like this carb has power valves and this is my next check..along with new needle/seats and floats..
Thanks

jmark, how about a 9377-2 dominator?
What is a good 1050? Thanks

quote:

Originally posted by jmarkaudio:
Bad floats, or N&S need replacing. I would start with a good cleaning, kit, and floats. And the 8896 calibration sucks...

really strong chance power valve is bad,i assumed it was lugged.still a good idea at this point .lug and go u roughly 6 jets to start

quote:

Originally posted by Coloradoracer:
It needs a brand new billet carb from Lightning Carbs. Easy fix!!!



Ok, couldn't help it....had to throw that in there!

Great advice

I don't know about a new billet carb but if you get tired of screwing with it then box it up and ship it to Mr. Whitener. He's done a great job for me. Good luck!

Let’s assume that you don't have any fuel pouring out of the booster and your idle air bleeds aren’t full of chit. The 1st thing i would do is take it off and see how much transfer slot you have exposed. If it’s between .020-.040 your GTG, if not you need to add more air or take away fuel. Since that model doesn’t have screw in IFR you need to add some air. The Idle Air Bleed Size should be a .053, look to make sure someone hasn’t changed it. As bad as your idle sounds I would go up 10 sizes to a .063 on both the primary and secondary and see if that helps. The one thing you didn’t say was how responsive the idle mixture screws are, if best idle is achieved with less than 1.5 turns, then the idle circuit needs some work. According to Holley that model doesn’t have a power valve.


joe

quote:

Originally posted by bullcutter:
OK, lowered the fuel to the bottom of the sight glass, seemed to help but still loading up.
Air bleeds are adjustable.
As I left the shop today I thought about the powervalve...I forgot about this because mine are blocked so I looked on the interned and it looks like this carb has power valves and this is my next check..along with new needle/seats and floats..
Thanks

A Holley 9375 is a good 1050 for general use...single carb.

I've had a number of them and they run ok......and no power valves.....

Had stock ones, a Davinci and a Stinnett and an APD Alcohol 1050 and all ran well......and no POWER VALVES IN ANY OF THEM...

Used them on 454's to well over 500 cubes and my present 565 has a Quick Fuel 1050 on it......

OK, Carb is off and in pieces. Idle transfer slot was 3 to 4 times what is should have been. Jets front 94 rear 100 and both had the smaller jet at a 45deg. angle on each side and just looked to be about .050 in diameter, just guessing. Also had a power valve in the front and I cannot find any markings or numbers on it. Needle and seat only has an "F" for number, no other markings. Air bleeds were the 2 on the inner both front and back were 40, the outer which were 2 pairs on each side both front and back were 51.
OK,
1) What size needle and seat do I need?
2) Do I plug the power valve and up the jets
and if so how much? And if I leave the PV
what size to run?
3) Air bleeds OK?

Thanks for everyone's help

quote:

Originally posted by bullcutter:
OK, Carb is off and in pieces. Idle transfer slot was 3 to 4 times what is should have been. Jets front 94 rear 100 and both had the smaller jet at a 45deg. angle on each side and just looked to be about .050 in diameter, just guessing. Also had a power valve in the front and I cannot find any markings or numbers on it. Needle and seat only has an "F" for number, no other markings. Air bleeds were the 2 on the inner both front and back were 40, the outer which were 2 pairs on each side both front and back were 51.
OK,
1) What size needle and seat do I need? .120
2) Do I plug the power valve and up the jets
and if so how much? go back to stock 88's front and rear And if I leave the PV
what size to run? power valves are used for the street. shouldn't have one in it.
3) Air bleeds OK? not even close!!! whoever changed them didn't have a clue. go back to stock outside 53 middle 63 inside 40's. that's stock!

Thanks for everyone's help

Whoever messed with that carb must of hated money and like to burn fuel. When i get something like that i start with stock and it's usually too rich. lol https://www.holley.com/product...nator/parts/0-8896-1

edited for punctuation

This message has been edited. Last edited by: sr4440,

Good advice...

That carb is a hot mess, LOL

Stop guessing, obviously someone has completely messed it up.....send it to Mark and end the nightmare.

Bob

quote:

Originally posted by sr4440:

quote:

Originally posted by bullcutter:
OK, Carb is off and in pieces. Idle transfer slot was 3 to 4 times what is should have been. Jets front 94 rear 100 and both had the smaller jet at a 45deg. angle on each side and just looked to be about .050 in diameter, just guessing. Also had a power valve in the front and I cannot find any markings or numbers on it. Needle and seat only has an "F" for number, no other markings. Air bleeds were the 2 on the inner both front and back were 40, the outer which were 2 pairs on each side both front and back were 51.
OK,
1) What size needle and seat do I need? .120
2) Do I plug the power valve and up the jets
and if so how much? go back to stock 88's front and rear And if I leave the PV
what size to run? power valves are used for the street. shouldn't have one in it.
3) Air bleeds OK? not even close!!! whoever changed them didn't have a clue. go back to stock outside 53 middle 63 inside 40's. that's stock!

Thanks for everyone's help

Whoever messed with that carb must of hated money and like to burn fuel. When i get something like that i start with stock and it's usually too rich. lol https://www.holley.com/product...nator/parts/0-8896-1

edited for punctuation

This is a 8896-3, not-1, air bleeds are closer. Is it too far off to try and correct or wasting time?
Thanks

Holley doesn't show a 8896-3. I would call Holley's tech line and ask them what the stock specs are. Because there is nothing online

1-866-464-6553

Let me know what you find out.

Ok, bored at work today, on 17 Dec 2013 Holley changed the part number from 8896-3rd to 80903RD This should be your carb.

you have a 5.5 Power valve and the jets are 84 front and rear. Air bleeds are IAB 53, IAB 63 and HSAB 40. easy fix put it back to stock.

https://www.holley.com/product...ator/parts/0-80903RD

Superseded info https://www.motorstate.com/sit...rsor=17#goto29882971

Joe

This message has been edited. Last edited by: sr4440,

If I go up on the air bleed say from .051 to .061 on the idle circuit or the high circuit. Does this give it more air or pull more fuel? Is there a different effect on each?

Thanks