holly set up

[personaltrainer]

Hey guys. I'm new here and look forward to hangin out. I purched a 86 jimmy (pics to come) and recently had my mechanic put a holley 570cfi on it with an edelbrock aluminun intake. I noticed that the truck definatly runs smoother (but not smooth) and a little better pick up but it seems like the secondaries are not opening up like they should and the electric choke seems to work "off and on". I have switched the spings out and tried them all but the secondaries still don't want to open all the way. He basically bolted the carb and intake on and set the timing and let me have the truck back - does this thing need to be dialed in or what? or is that all of the performace i should be getting? BTW I'm looking at 8-10mpg on the road with a 305 - sounds wierd, no? Thanks in advance. I'm gonna take it back to him sometime next week but I'd like to have something to tell him specific.

 

[mrk5]

Couple of questions. What do you mean that the choke works "off and on"? And why do you think the secondaries aren't opening?

 

[wraenking]

if your secondaries arent openeing it sounds like a float problem. if you have the glass windows to see the fuel level with that carb, you want the fuek level even with the bottom of the window.

 

[personaltrainer]

I'll check the window in a minute. The reason that i think the secondaries are not opening is because it doesn't sound like it. With the new intake and all there should be a noticable sounds when the pedal is wide opened or close to it, no? What about the mileage - that sound right? I do not care what the mileage is - I'm only mentioning it as it might be a clue as to weather the carb is set up correctly. Mrk5 - looks like your truck is yellow - I've got the yellowest truck on earth. I'll post some pics soon!
Lemme know what ya'll think. thks

 

[personaltrainer]

choke working "off and on" = sometimes when I start it, it takes a few tries to get her running and then I have to hold the gass pedal for a few minutes to get her warmed up. other times the choke works and drops off when she is warm. My other trucks w/ electic chokes worked better. I just pumped the gas twice and turned the key they started, revved and when I tapped the gas again the choke fell back. That was with edelbrock though (hate to say it).....

 

[mrk5]

Check the linkages, both the choke and secondaries. Make sure there isn't a bind in the choke, and also make sure the throttle linkage is traveling far enough to open the secondaries.

The best way to ensure that the secondaries are or are not working is to wire them closed. Then you know for sure they are closed. Then go out and see if you can tell a difference.

Don't know about the edelbrock, but remember the Qjet has much larger secondaries. So IMO, the secondaries on the Qjet are much louder than your holley that has equal size pirmary and secondary bores (I'm assuming).

The only other thing I can say on the choke is check the voltage on the power wire at those times you don't think it is working.

If you're taking it back to the guy that installed, just be sure to tell him all the things that you have observed.

My truck is actually 1970 Plymouth Lemon Twist yellow. I'm into Mopars for muscle cars, that's why I chose that color.

 

[personaltrainer]

Mrk:
cool. I'll play with it some more tomorrow. Thanks for the input. I guess it could be that the seconadaries are just not as large as they were on the Qjet that I had on the other truck, huh? I talked to a guy who tunes race cars and he said that for $50 he could hook it up to a computer and get the holley dialed in - not sure of the computer or whatever but do you think it's worth a try (even though I've already paid my mechanic to instal and tweak the thing?)

I was not crazy about teh yellow color at forst and could not wait to get it painted but it's growing on my now! Maybe I'll leave it.

 

[mrk5]

Me personally, I would probably have it done. I'm sure the computer he's talking about is using air/fuel ratio.

I know enough about carburetors to be dangerous. I can tune idle mixture in pretty good, but beyond that I haven't had much luck yet. Haven't ever messed with jetting and such. I think I need to because of the altitude where I live.

I just really like having a well tuned carb. If it's not you're only cheating yourself out of potential performance.

Everyone ragged me about the yellow before I painted it. After it was done, they all decided it wasn't so bad.