[ck67goat]

Does anyone else run a Holley 950HP or a Holley with the downleg boosters? Mine seems very temperamental at idle and cruising up to 2500 rpm. It likes to drip fuel out of the boosters and that makes it run really rich. The Holley tech line says this is normal and even at part throttle it should spew lots of fuel. They claim that the fuel atomizes once it enters the intake, but in actuality I'm getting too much fuel pooling on the butterflies and eventually starts to foul out the plugs. It is way too fat between idle to 3000 rpm. I've had the thing apart, changed power valves, ran w/o power valves changed jets, squirters, etc. etc. It runs like a champ at top end but I'm getting ready to throw in the towel for another carb because it is becoming undrivable on the street and just reeks of fumes. Anyone figure out how to make these streetable? Surprisingly, the car will idle at 975 rpm and in gear about 700, even with the big roller cam I'm running.

[70judgeconv]

ON mine I opened up the idle air bleeds 4 sizes and went down 2 sizes on the idle feed restriction.Idles at 800 and drives like a dream, no flat spots no hesitation and street driven regularly . Mines is an ultra series so even the idle restrictions have jets. All carbs need attention to make every thing perfect try one thing at a time .

[BDHABT]

Originally Posted by ck67goat

Does anyone else run a Holley 950HP or a Holley with the downleg boosters? Mine seems very temperamental at idle and cruising up to 2500 rpm. It likes to drip fuel out of the boosters and that makes it run really rich. The Holley tech line says this is normal and even at part throttle it should spew lots of fuel. They claim that the fuel atomizes once it enters the intake, but in actuality I'm getting too much fuel pooling on the butterflies and eventually starts to foul out the plugs. It is way too fat between idle to 3000 rpm. I've had the thing apart, changed power valves, ran w/o power valves changed jets, squirters, etc. etc. It runs like a champ at top end but I'm getting ready to throw in the towel for another carb because it is becoming undrivable on the street and just reeks of fumes. Anyone figure out how to make these streetable? Surprisingly, the car will idle at 975 rpm and in gear about 700, even with the big roller cam I'm running.

Contact Shaker455HO on this board;he does wonders for carbs.He made my 1050 and Victor combo very streetable.

Mark.

[70judgeconv]

one more thing take a vacum reading and put in a power valve that is 2-3 points lower than vacum at idle i did that as well.

[shaker455]

CK67,
The HP950 has a lot of draw backs and is difficult to tune.

In short the boosters are too large for the size venturi hence your overly rich condition.

With those I usally add screw in transition jets into the mainbody to balance part throttle/cruise, resize the IFR and airbleeds, add a bypass system.

The end results are a great running unit!

[ck67goat]

Originally Posted by shaker455

CK67,
The HP950 has a lot of draw backs and is difficult to tune.

In short the boosters are too large for the size venturi hence your overly rich condition.

With those I usally add screw in transition jets into the mainbody to balance part throttle/cruise, resize the IFR and airbleeds, add a bypass system.

The end results are a great running unit!

Shaker455, I have one of the first HP's that came out. I'm not sure how to add transition jets unless the main body is machined to accept? The other changes, is this something I can do on my own or need to send out?

[shaker455]

CK,
The transition jets is a machined in process so that would be something you would send out also is the4 IFR unless they screw in and if you have an early one I believe they press in.

[Tom Vaught]

Shaker call me at home

Tom V.

[shaker455]

10-4

[70judgeconv]

What is a rough cost for these modifications and what kind of time frame?

[shaker455]

PM for a quote