Slant Six Forum :: So a holley 390 works pretty well? What about this one?

I thought at one time Slantzilla had run one of these on his car a long yarn back.... It will not be for daily driving or cold weather start ups (under 60 degrees...warm weather without a lot of pump shot to get it started).

You will have to make sure to recalibrate the acc cams, pump shots, jetting, and if the power valves are just plugs you will have to up the main jets 4 sizes to cope (hence it's a track carb as there will be enrichment once the mains tip in)...so jets will start at 55-56 with gas if you keep the plugs to start.

I would estimate it would work better on a Clifford shorty, and the engine build would need to be a minimum of one of the 10:1 SCR 270+ cam engines (and probably would shine on an 11:1+ with a 280 cam with .5 lift characteristics...)...That being said...at those performance levels...the engine will want more carb at the track and a shift to a 500 cfm carb would be next anyway...

If it went on a h-pak manifold I would split the plenum and mount the carb so you can dial in each side of the carb independently.

But that's just my 2 cents...

Author:	drgonzo [ Thu May 07, 2015 11:24 am ]
Post subject:	So a holley 390 works pretty well? What about this one?
A friend brought this by and said, "try this out." So I guess I will. Interesting carburetor. A Holley 390 spec carburetor for some circle track application. I have yet to pull one of the bowls but will before I mount it. It came with two extra sets of metering blocks which appear to be set up for alcohol as they have no power valves but only an aluminum fixture with one rather large hole in it. It has no numbers stamped on it anywhere.

Author:	J S Goldman [ Thu May 07, 2015 12:07 pm ]
Post subject:	holly 390
just curious is it going on a street car or a race car? what intake manifold are you going to use?

Author:	drgonzo [ Thu May 07, 2015 12:19 pm ]
Post subject:
I have two intake manifolds, an Offy and and H-Pak. I would think I would most likely only use this carb at the track. Right now I am getting ready to swap engines in my car so it might be a lil while before I can try it out. My car will not be a daily driver and I am not concerned with stop and go traffic or cold weather drive-ability, etc. I don't know that I can make this carburetor work for any application on my car but it will be fun finding out. After closer inspection, the metering blocks do have provisions for power valves but have some sort of 'hat' over them. The carburetor looks very much like a number 0-80507-1 that has been further modified by someone.

Author:	DusterIdiot [ Thu May 07, 2015 5:42 pm ]
Post subject:	Yep...
I thought at one time Slantzilla had run one of these on his car a long yarn back.... It will not be for daily driving or cold weather start ups (under 60 degrees...warm weather without a lot of pump shot to get it started). You will have to make sure to recalibrate the acc cams, pump shots, jetting, and if the power valves are just plugs you will have to up the main jets 4 sizes to cope (hence it's a track carb as there will be enrichment once the mains tip in)...so jets will start at 55-56 with gas if you keep the plugs to start. I would estimate it would work better on a Clifford shorty, and the engine build would need to be a minimum of one of the 10:1 SCR 270+ cam engines (and probably would shine on an 11:1+ with a 280 cam with .5 lift characteristics...)...That being said...at those performance levels...the engine will want more carb at the track and a shift to a 500 cfm carb would be next anyway... If it went on a h-pak manifold I would split the plenum and mount the carb so you can dial in each side of the carb independently. But that's just my 2 cents...

Author:	slantzilla [ Thu May 07, 2015 6:04 pm ]
Post subject:
Yes, I had one. It is a NASCAR Truck series carb from a few years ago. I used it for awhile, but I am pretty sure Ceej ended up with it.

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So a holley 390 works pretty well? What about this one? https://slantsix.org/forum/viewtopic.php?t=57651	Page 1 of 1

Author:	DusterIdiot [ Thu May 07, 2015 7:23 pm ]
Post subject:	Lol....
Quote: I used it for awhile, but I am pretty sure Ceej ended up with it. That's why he swears by Edelbrock.... I always wondered why he swore a lot then changed carbs... I guess that's payback for taking a picture of your cat, right?

Author:	drgonzo [ Fri May 08, 2015 6:16 am ]
Post subject:	Re: Yep...
Quote: I thought at one time Slantzilla had run one of these on his car a long yarn back.... It will not be for daily driving or cold weather start ups (under 60 degrees...warm weather without a lot of pump shot to get it started). You will have to make sure to recalibrate the acc cams, pump shots, jetting, and if the power valves are just plugs you will have to up the main jets 4 sizes to cope (hence it's a track carb as there will be enrichment once the mains tip in)...so jets will start at 55-56 with gas if you keep the plugs to start. I would estimate it would work better on a Clifford shorty, and the engine build would need to be a minimum of one of the 10:1 SCR 270+ cam engines (and probably would shine on an 11:1+ with a 280 cam with .5 lift characteristics...)...That being said...at those performance levels...the engine will want more carb at the track and a shift to a 500 cfm carb would be next anyway... If it went on a h-pak manifold I would split the plenum and mount the carb so you can dial in each side of the carb independently. But that's just my 2 cents... DI, I stated above that my car is not a daily driver and I am not concerned with cold weather starting. I used to race dirt track hobby stock cars in the 80s. We used a Holley 1850 600cfm carburetor as a 'spec' carb. We were tuning them for a specific application I realize, but tune them we did. Even went as far as to mount them backward so the side hung floats would not shut off during cornering. My engine will be a 10:1 SCR, 276/.470"cam, ported head with larger valves set up. I like the plenum divider idea on either manifold. Thanks for the good input.

Author:	slantzilla [ Fri May 08, 2015 5:44 pm ]
Post subject:
The biggest tuning secrets to Holleys are: 1. Don't buy some piece of crap someone else has "supertuned". 2. Change jets and power valves and leave it the flock alone. Watch the guys with Carters and Edelcraps and see how much they are really working on their " troublefree" carbs.

Author:	drgonzo [ Fri May 08, 2015 7:57 pm ]
Post subject:
Quote: The biggest tuning secrets to Holleys are: 1. Don't buy some piece of crap someone else has "supertuned". 2. Change jets and power valves and leave it the flock alone. Watch the guys with Carters and Edelcraps and see how much they are really working on their " troublefree" carbs. If that advice is for me. I haven't bought anyone's crap. I was given the carburetor to try and the owner doesn't know a lot about it. While it is 390 based with 1.46" throttle bores I would bet it flows considerably more than 390cfm. It's not the only carb I am going to use. I have quite a few, 2v and 4v, Holleys, Autolites and Edelbrocks. Lots of ways to skin a cat.

Author:	spacecommander [ Sun May 17, 2015 3:04 pm ]
Post subject:
I think that carb is restricted to 390CFM but based upon a much larger carb - with much larger throttle plates, bleed circuits, etc. Anything can be made to "work" - but how much effort do you want to put in to it? Will it be so lean at idle you end up adjusting it so that when at part throttle you're flooding the engine?

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