Damn holleys

[pandamarie]

After cruising my 440 six pack challenger around today I found it running to lean constant lean miss fire till I got into the two outer carbs, got it back home and pulled the sight plug to find the float level about 1/2 inch low, as soon as I put the screwdriver on the needle seat adjusment screw and gave it a turn to loosen it the whole needle assembly popped right out of the carb spewing fuel everywhere. Now I have to find a new center bowl. Holley has to make them and its 4-6 weeks, so I guess any 4150 center hung bowl will work for now as long as the inlet is on the right side. Does anyone know? any ideas on how to fix the stripped threads in the float bowl?

[72hemi]

  That sucks!! I hate holleys too (mostly I don't like tuning them). That's why when I did the multi-carb setup on my 340 Challenger T/A clone, I went with 2 4's instead, (plus it gets a lot of attention 'cuz it looks stock with the hemi air cleaner and "340 EIGHT PACK" decal on the air cleaner.

[Chryco Psycho]

Holley part # 134-103 should work on the 6 pack
 a front race bowl should work ok for you on the center carb only

[pandamarie]

Thanks Cryco, thats what I have on order from summit, should be here tomorrow.

[GreenFish]

I actually prefer the Holley type carb.. I run a BG demon and ill never go back

[Chryco Psycho]

  , at least with the Holley Demon & Proform style you can adjust the float level from the outside with it running , there is no way to adjust the Carter style to correct float level to compensate for varying fuel pressure depending on the fuel pump used

[GreenFish]

That's what I like about the "holley" style carbs. the adjustability. I'm no pro at it but im getting better and better at it. I think it just takes practice and patience, once you get it , you will prefer the holley over the AFB type.   Just my opinion

[Mopar God]

We were sponsored by Holley for 3 seasons and I really like their carburetors. I found some of the following information in some old tuner's notes and FAQ's I have written:

Steve,

Thanks for the compliments. Here is the data you requested...The white cam (#218) often discolors and looks pink or orange. The accelerator pump cam kit (#20-12) contains ( pump cams. Screw position #1 yields the fastest shot and the least duration. Screw position #2 yields a longer duration pump shot as does screw position #3.

The cams are listed by color and pump volume from lowest to highest:

White, Blue, Red, Orange, Black, Green, Pink and Brown.

I would also recommend the hollow discharge nozzle (squirter) screw available under part #26-12. This is not normally used under a .039" squirter, but I like to use it in conjunction with a .028" nozzle. This works in 99% of Holley street applications, even with a fairly stout camshaft and low manifold vacuum.

Keep going up in shooter size until a puff of black smoke comes out the exhaust, then go back one or two sizes.

Hope this helps...Robert

[Mopar God]

Regarding transfer slots:

Greg,

When wroking with the transfer slot relation to the throttle blades, anywhere from .020" to around .045" will work. Less of the slot exposed for a slightly lower idle speed and a bit more exposure for a slightly higher idle speed.

The transfer slots should not actually flow fuel at idle, but rather the low pressure signal from airflow passing by the slot keeps the fuel ready to flow the instant the throttle is opened. ]

This is truly a teeter-totter adjustment.

On a vacuum secondary without 4 corner idle, I set the throttle to 1/2 turn from closed and leave it alone, just as previously posted. With 4 corner idle, I try to match the positions of the front and rear transfer slots equally.

Keep in mind that some mechanical secondary carbs have an idle bypass screw under the air cleaner stud. Always check for the presence of the screw before drilling the throttle plates.

For the record, I do not like 4 corner idle as a matter of personal taste...Robert

[Mopar God]

Some notes from an article on Holley power valves:

Roger,

I set a 750 Mechanical Secondary up for a friend once and installed a 5.0 in/hg power valve to correspond with his 10 in/hg of vacumn at idle. He drove the car and liked the results. He later asked me how I selected the power valve. I told him and he asked that I install an 8.0 in/hg valve instead based on another person's expert advice.

What we discovered was a driveability problem when the clutch was quickly released and then pushed back in, like when trying to cross a busy freeway and then hesitating.

The vacumn drops quickly past that 2 in/hg safety margin and enrichment starts immediately. We quickly changed it back to my previously selected 5.0 in/hg valve.

I think this method (2 in/hg) would not cause a problem with an Automatic Transmission.

I haven't used a Holley since we quit running our SS/a car in 1990. Every once in a while, I find myself helping someone set one up. Glad I kept my notes all these years!!!

Best of luck...Robert