opinion on engine mods

[jlangholzj]

yes and no, although it help when you punch it, it also add gas all the time you apply pedal. my idle is set around 850 and that's why i thought the short lived rev to 1500 was a sign of a rich mixture. what i was talking about was a slow steady acceleration.

 

[D.Hearne]

If you didn't throughly clean all the tiny passages in the metering block and throttle body, your problem may be a blocked passage. I learned this the hard way in rebuilding Holleys. I always make damn sure all these passages are free and clear before reassembly. Blow them out with compressed air and then with spray carb cleaner (wear glasses for this) and observe that all are clear. If you've got a list 1850 or 80457 600 cfm carb, the 6.5 PV and 66 jets sound correct. Also check that the check valve is present under the accellerator pump nozzles, if it's not it could pull extra fuel thru that circuit under high vacuum conditions.

 

[jlangholzj]

like i said, i pulled it appart untill i was left with just the body. however i failed to mention that it DOES NOT happen at higher speeds, only from a stop or a very slow crawl. before and after the little blip, it just purrs.

check valve...give me an idea about what i'm looking for plz.

keep in mind that this is on a stock 289 other than a performer in take, ratio411 i already know your oppinion on this

 

[D.Hearne]

Remove the squiter nozzle in the throttle body and look down in the screw hole. There should be a solid metal pin about the same diameter as the hole under the screw. It's about 1/8" diameter and 3/8" long. It's pointed at the bottom end. When the pump shoots fuel, it raises this check valve pin. rod, (whatever you want to call it) up to let the fuel stream pass.

 

[jlangholzj]

makes sense, i'll look tonight to make sure. but assuming its in there, im guessing i need a smaller squirter size?

 

[D.Hearne]

If you were not aware of that check valve, chances are it ain't there now. It would have likely fallen out of the hole in handling the T/ body while cleaning.

 

[ratio411]

makes sense, i'll look tonight to make sure. but assuming its in there, im guessing i need a smaller squirter size?

It's very hard to diagnose a carb over the net...

On the squirter:
25 is a very good mild squirter.
I would not focus on it, that is one of the smallest squirters anyway.

If you are still focused on the accel circuit:
Look at the cam. What cam is it?
What linkage location is it in?
What cam hole is the screw located in?
Do you have an umbrella or BB pump valve?
Did you reinstall the restrictor below the squirter?
What model carb are you working on?
What gear ratio do you have?

To do this right, we need LOTS of info.

 

[Kagan]

another question came to my mind today. It is not relevant to the new parts. I want to ask you about the vacuum secondaries. If I am not wrong my autolite 4300 has the vacuum secondary option. It means that the 2 barrels work with the vacuum right? But how does it work? Or how can I know if they really open up at the right time??

My car has a spacer too. There is a hole on the spacer by the way. What should be the correct way of attaching everything there between the manifold, carb and this spacer?? Is there a plot or a schematic diagram available? I want to make sure my mechanic connected them right.

If it's important, I have an electronic distributor too. (Proform Street/Strip HEI Distributor)

 

[D.Hearne]

The carb spacer either has the PCV hose plugged into it or the EGR system cast into the spacer.

 

[Kagan]

but how do I connect all those? If someone could tell it step by step it would be great. I have been looking for info about the carb but couldnt find anything useful.