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colorado51
09-13-2004, 10:29 AM
Ok you guys and gals, the wife and I are leaving Wednesday for a 12-day vacation in Maui. So, I thought I would leave you with a short and sweet tech post.

Don’t know who all noticed or not, but last week there was a pretty good post on Holley carbs ( http://www.jalopyjournal.com/ubbthreads/showflat.php?Cat=&Number=541293&page=&view=&sb=5&o =&fpart=all&vc=1 ), so I thought I would expand on that a little.

Holley’s are really pretty simple, and if you run one, you will probably end up having to change the jets / power valve a few times to get it just right. Here is a simple way to do that.

Here is the subject, my 51 Chevy with a Holley 3310. You will notice that I have cut a section out of the cheap chrome dual feed fuel line (left side of carb) and replaced it with a piece of rubber fuel hose.
http://img.photobucket.com/albums/v159/rockahula/51%20Chevy/P0001382.jpg

Ok the first thing I do is barley loosen all the float bowl screws (so you don’t warp the float bowl or metering block). Then with a cup under one of the lowers screws, I remove that screw and drain the fuel out of the bowl in to the cup.
http://img.photobucket.com/albums/v159/rockahula/51%20Chevy/P0001383.jpg

Remove the rest of the screws. Remember how I said I cut the chrome dual feed inlet line and added a piece a rubber fuel hose? That is so I can swing the float bowl out of the way without removing any on the fuel lines. So there you have it, jet changes without removing the carb in less than 15 minutes without getting fuel all over the place or loosening any fuel lines.
http://img.photobucket.com/albums/v159/rockahula/51%20Chevy/P0001384.jpg

Also, in my case, Im running this on a pretty much stock 454. These 3310 (750cfm) Holleys have a tendency to run rich at idle no matter how well you have it tuned. A good remedy for this is to drill a .089 (#43 drill) hole in each primary butterfly.
http://img.photobucket.com/albums/v159/rockahula/51%20Chevy/P0001385.jpg

Slide
09-13-2004, 11:00 AM
Thanks, c51! I am really learning a lot about this stuff! Keep it coming!

Sorry to hear about your trip to Maui. I mean it's gonna be rough getting away from the car and your job and stuff, but I'm sure you'll survive. http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

colorado51
09-13-2004, 12:18 PM
[ QUOTE ]
Thanks, c51! I am really learning a lot about this stuff! Keep it coming!
Sorry to hear about your trip to Maui. I mean it's gonna be rough getting away from the car and your job and stuff, but I'm sure you'll survive. http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

[/ QUOTE ]

Did you get yours running any better?

Slide
09-13-2004, 12:32 PM
It's doing a little better. I doing the baby steps on adjustments. Adjust a little, drive a lot, adjust a little drive a lot, etc.

It still doesn't feel as "crisp" as I think it ought, but it's way better than the Carter I had. I want to try bumping the timing up just a little, tho. (Maybe tonite?). That's kinda what it's feeling like it needs right now.

My dad's coming into town in a couple weeks, and he knows a little more than I do on general engine tuning (but not specifically Holleys), so I'll see what he knows.

Thanks again for your help on this. (And everybody else's too!).

I'm gonna be askin' you alotta questions once I start puttin' the 4-speed in the car.

Hot Rod To Hell
09-13-2004, 12:50 PM
One other quick tidbit to add...

If you smear the floatbowl/metering block gaskets with chapstick or vaseline when you put it back together you can get MANY changes out of a single set of gaskets.

colorado51
09-13-2004, 03:10 PM
[ QUOTE ]
One other quick tidbit to add...

If you smear the floatbowl/metering block gaskets with chapstick or vaseline when you put it back together you can get MANY changes out of a single set of gaskets.

[/ QUOTE ]

Great idea, those blue Holley gaskets get kinda sticky after awhile.