New To Holley Carburetors

[Bodyperson]

And not all that rehearsed in other carburetors. A friend gave me an old 600 DP and I recently started playing with it. I pulled a bowl off and ya, it was put away wet. It doesn't look too bad. Accelerator pump has some cracking. It obviously needs a kit. What really caught my eye was the limited opening of the throttle plates, primary and secondary. Looking at the linkage and what not, I was able to get the throttle plate to open up to what seemed like a more acceptable angle, virtually in line to the venturi tubes. It took some grinding of this and that but I think I really improved the potential of this carburetor. Is this a normal exercise in Holley tuning or was it a total waste of time.

 

[RustyRatRod]

Sounds unusual to have to grind on one to get the blades to open vertically.

 

[Bodyperson]

Sounds unusual to have to grind on one to get the blades to open vertically.

Most of it was the secondary hitting the choke housing. I suppose some pictures would help. I'm not really keen on all of the part terminology.

 

[a-bodyguy]

Most of it was the secondary hitting the choke housing. I suppose some pictures would help. I'm not really keen on all of the part terminology.

shoudnt be possible
is it a 4776 ?

 

[Bodyperson]

shoudnt be possible
is it a 4776 ?

Yup. This is the grinding.

 

[a-bodyguy]

need a side angle shot

 

[Bodyperson]

Lil on the primary too.

 

[Bodyperson]

Side angle

 

[a-bodyguy]

As i thought those are your acelerator pump arms
shoudnt have to do that

 

[Mattax]

Where's the cam?

 

[Bodyperson]

As i thought those are your acelerator pump arms
shoudnt have to do that

Well I did, lol. Here it is standing on end at WOT. Just barely not touching.

 

[Mattax]

Well I did, lol. Here it is standing on end at WOT. Just barely not touching.

View attachment 1716232593

OK I see the screw there for the pump cam

Here's a double pumper with the choke removed. Is anything different on your causing interference other than the choke?

arrow just points to the screw holding the pump cam.

 

[Bodyperson]

OK I see the screw there for the pump cam

Here's a double pumper with the choke removed. Is anything different on your causing interference other than the choke?
View attachment 1716232599
arrow just points to the screw holding the pump cam.

Nope. A little on the primary. Should yard the choke I suppose. Just using this carb as a learning tool.

 

[a-bodyguy]

pump cams look fcked up stop grinding lol

 

[Bodyperson]

pump cams look fcked up stop grinding lol

I'm a bodyman, thats our first reaction to everything. lol. I really didn't see any other option. Cam looks fine. I should have cleaned the POS first.

 

[a-bodyguy]

1000% dont need to do that something ison wrong or installed wrong

 

[Bodyperson]

1000% dont need to do that something ison wrong or installed wrong

I don't think so. It wasn't that much. Maybe 2 or 3 degrees from square to the venturies

 

[a-bodyguy]

I don't think so. It wasn't that much. Maybe 2 or 3 degrees from square to the venturies

you think holley sold there carbs and they need to be grinned on? cmon
iver run holley dp for 44 yrs not a 1 needed that 4776 4777 4778

 

[Newbomb Turk]

If the secondary linkage wasn’t hitting, you bend the little link between the primary and secondary throttle blades until they are straight up and down.

On the primary side, what you did is exactly what you do. That’s the only way I know of to fix it.

It doesn’t happen much with newer carbs but the older Holley stuff probably needs help about 40% of the time.

It should always be checked with any carb.

 

[Bodyperson]

you think holley sold there carbs and they need to be grinned on? cmon
iver run holley dp for 44 yrs not a 1 needed that 4776 4777 4778

I didn't say it "needed it", as a matter of fact, that was my question. I also edited my initial post because I said perpendicular but you guys were kind enough to read past that mistake.

 

[Bodyperson]

If the secondary linkage wasn’t hitting, you bend the little link between the primary and secondary throttle blades until they are straight up and down.

On the primary side, what you did is exactly what you do. That’s the only way I know of to fix it.

It doesn’t happen much with newer carbs but the older Holley stuff probably needs help about 40% of the time.

It should always be checked with any carb.

I could have bent the rod but the stoppage is built into the carb.

 

[Newbomb Turk]

I could have bent the rod but the stoppage is built into the carb.

Yeah, I get that. My point is if after unscrewing the parts clashing if the secondary throttle blades still weren’t fully open, you bend the link.

Or, if you are a bucks up kinda guy you can buy an adjustable link and you can custom Taylor the rate of secondary opening right up to 1:1.

 

[Bodyperson]

Yeah, I get that. My point is if after unscrewing the parts clashing if the secondary throttle blades still weren’t fully open, you bend the link.

Or, if you are a bucks up kinda guy you can buy an adjustable link and you can custom Taylor the rate of secondary opening right up to 1:1.

I realized you were actually agreeing with me after my post. lol.

 

[Bodyperson]

Yeah, I get that. My point is if after unscrewing the parts clashing if the secondary throttle blades still weren’t fully open, you bend the link.

Or, if you are a bucks up kinda guy you can buy an adjustable link and you can custom Taylor the rate of secondary opening right up to 1:1.

I have to wonder why 1:1 is not the default application. It seems like it would warrant better fuel distribution.

 

[RustyRatRod]

I didn't say it "needed it", as a matter of fact, that was my question. I also edited my initial post because I said perpendicular but you guys were kind enough to read past that mistake.

I've never seen that, I must admit. It seems the mods you did worked though, so I wouldn't sweat it.