Holly 3310

[Wizo]

Howdy folks: I real could use some professional advice please.
Is a holly 3310 ( 750 double pump, vac secondaries)to much carb for a small block 400? it has #72 jets it. The engine; 400 cid bored out .30 0ver, 2.02 heads, 268ex cam, 9.01-1 compression, 2000 stall converter, TH400, 3.73 posi out back.
Every time i start it up from cold it fouls out the spark plugs. i'm kinda a middle aged guy and don't have that much more hair to pull out trying to figure this out. Thanks for the help in advance.

[Fldawg]

it's not to big for that engine, you might want to check your float levels or see if your choke is adjusted right if its electric, if it's a manual choke check to see if its open all the way. hope this has helped

[geezer#99]

First off, a 3310 is a single pump vac secondary.
Second, it's just right for your motor.
Now the questions!
Manual choke or electric or some other type of choke?

[68Gold/white]

X2 on post 2
Perfect carb for that engine, the cam.....

What does it run like when it does run???

[dfrank]

3310's are not a double pumper nor is a vaccum secondary carb a double pumper. Now is it a 4150 3310 or 3311-1 which are 780 cfm or a 4160 3310 which is 750 cfm. I hihly doubt it is too much carb for the motor as I have ran a 780cfm 3310-1 4150 and a 750cfm 4150 holley ultra double pumper most recently. I would have to say that your carb just isn't set up right. Check your float bowls and see if your choke is staying on too long if it is an electric choke. Also check your fuel mixture screws and set them with a vaccum gauge to get the higest vaccum reading. You could also have too cold of spark plugs installed but I would check with the carb first.

[Wizo]

Hey everybody; thanks for the response. I wil check on each and every suggestion. It has a manual choke. I'm kinda wondering if the power valve is blown? I'm also hoping theirs enough timing, it's set for 12° BTC any Suggestions for a better timing setting?

[geezer#99]

Describe better what it does?
Do you use the choke to start it and run to warm a little?
What intake?

[Wizo]

when i start from cold,i close the choke half way,hold the throttle about half way open by hand ( trucks not streetable yet) and start cranking.It usually won't start this way unless i give it one full pump ( open the throttle all the way and close it) then crank again. it usually starts then but almost always has one or two gas fowled plugs. The manifold is a dual plane edelbrock manifold.

[geezer#99]

Close the choke all the way, pump it once, when it fires push the choke back in just enough to keep it on a high idle. As it warms up push the choke in a little more.
Is your high idle working?

[Wizo]

i think so. i'll check it out tomorrow and try to start it by your suggestion. to late tonight. i'll let you know how it goes.thanks for all your suggestions and help.By the way my names Ron.

[hamjet]

Sometimes if you don't let the engine warm up to operating temps to run for a while and constantly start cold, run for a bit, shut it off, repeat it over and over, it will foul out plugs.. I had a 64 nova I drag raced and I let a friend store it at his tire store over the winter. he kept driving it in and out of his garage every day. by the time I picked it up in the spring, he said something was wrong, he couldn't get it running. come to find out the plugs were fouled out and alot of gas in the oil pan. since yours isn't on the road yet, that may be the problem..

[geezer#99]

THe one problem I always had with manual choke holleys was when you started them cold. The choke isn't set up right. Not enough rpm for the right choke opening to get it to stay running.
I modified the choke cam. Ground a new curve into it.
On your carb Ron, you shouldn't even need the choke now while it's warm out. Just crank up the idle a couple turns, pump the pedal once and fire it up.
When you get it running look inside the carb for any raw fuel. If you see some you know your power valve could be blown or floats set to high.
Another job for you.
Remove that heat wrap off your headers. THey'll rot out quickly especially in your wet climate.

[Willys47]

Originally Posted by Wizo

when i start from cold,i close the choke half way,hold the throttle about half way open by hand ( trucks not streetable yet) and start cranking.It usually won't start this way unless i give it one full pump ( open the throttle all the way and close it) then crank again. it usually starts then but almost always has one or two gas fowled plugs. The manifold is a dual plane edelbrock manifold.

I had a problem very much the same check the vacum with the motor running at idle with a vacum gage. If the motor has a low vacum say 3 or 4 inches and the power valve in the carb is a for a higher vaum signal say 8 or more the valve will start to open adding more fuel when its not needed and this start fouling the plugs. The power valve is located in the front meetering block and it will have a number stamped on it indicating its vacum signal setting. Hope this helps.

[Wizo]

i was also told to screw the mixture screws in all the way and if the engine keeps running the power valve it kaput ski (blown). can't work on it till later today gotta do the family thing first. Of coarse.