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Discussion Starter #1
I just had a guy rebuild my carb. and adjust my timing, he said he set my timing to TDC, which doesn't seem right to me... The car is also a good noticeable difference slower than when I gave him the car. He said he also disconnected the secondaries on the carb, he said that it didn't need them. I've got a 306, and the carb is a Holley 4160 4bbl 600CFM. Anyone have any advice on why the car is slower??
 

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Discussion Starter #2
C'mon you guys, don't try and tell me that NO one on here that's read this thread knows anything about timing. Seriously.
 

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Heavily Medicated Crime Fighter
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Pull the spout connector and set the timing to 12 degrees BTDC. If the secondary side of your carb has been disconnected then all you have is a small two barrel carb and that will slow you right down. I take it is a mechanical secondary card and not a vacuum secondary carb. A 600 Holley is fine for a 306.

Regards

Mark
 

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Johnny Five is Alive, TCCoAAC Member
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I don't think he has a Spout. Its probably running old Duraspark system, needs to disconnect Vacum Adavance..
 

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You need the secondaries to feel the power you had before. Maybe he couldnt figure out the vacuum timing advance and disabled your vacuum secondaries to try to make up for it? I really dont know. Either way I would fully enable the carb, then time it again if it needs it.
 

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Discussion Starter #8
Yeah it was really rainy today so I didn't have a chance to go get a timing light and work that one out... I think I figured out through reading stuff online how to set the timing, although I'll have to take acloser look at my engine to know for sure. I will fix the timing tomorrow hopefully... also connect the secondaries if I can figure out how to do it haha. Any help??
 

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Pedal Faster
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If it's like the Holley 750 I had on my truck, there should be a little 1" piece of vacuum line running from the body of the carb to a diaphragm mounted on the side of the carb that controls the secondary linkage. It's been a while, but I think that's how it went.

Did the guy that disabled them say anything besides "you don't need them"? That sounds a little fishy to me...
 

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Discussion Starter #10
He said that the carb was too big for the engine and that it didn't need that much fuel. BTW Here is a picture of the side of my carb, someone point out what I'm supposed to do here...

<img src="http://members.tccoa.com/ironman569/CarPictures/Carb%201.jpg">
 

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Discussion Starter #11
Alright, you guys are slacking haha. I know it's the weekend but I need some help over here, I even posted a picture!! How do I reconnect my secondaries. Also, will someone come over to my place and show me how to adjust my timing?? HELP!
 

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Discussion Starter #13 (Edited)
Here ya go. I posted that picture because I thought the vacuum hose for the secondary was on the passenger side of the carb... at least that's wherre Dode said he thought it was, but alrighty here is the other side.

<img src="http://members.tccoa.com/ironman569/CarPictures/Carb%202.jpg">
 

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Discussion Starter #14
As a side question, my choke plate is kinda stuck open, and I think it's causing my engine to try and stall out given accelleration. It's kinda cold out btw. I don't know why all of a sudden the choke plate is stuck like that. Help?
 

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Pedal Faster
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Choke is stuck open or closed?

When the car is warmed up and at warm idle, the choke should be fully opened.

Adjust it with the car cold:

Push the throttle to the floor once so the choke closes. Hold the choke cap and loosen the screws that hold it down. Turn it to open the plate more, or the other way to close it. It shouldn't be closed completely, somewhere between an 1/8 and a 1/4" depending on what your motor likes.

As for the secondaries, I cannot for the life of me remember what the vacuum routing looks like, but I can almost say for certain that the loop of vacuum hose you have on the side of your carb isn't right. Take it back to the guy that disconnected them, tell him it's way down on power, you want it hooked up right.

Good luck!
 

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Pedal Faster
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Okay, in that diagram... that's what you should be seeing under the timing light now. The light flashes when that line on the harmonic balancer lines up with 0 on the indicator.

To advance the timing, check to see if your distributor has vacuum advance (if it does, there will be a vacuum hose leading into a can on the front of the distributor) and if so, disconnect the vacuum line and plug it. Make sure the car is at low warm idle.

Point your timing light at the harmonic balancer and indicator plate and make a note of what the timing is. Your indicator plate may say something other than "BTDC/ATDC". BTDC (before top dead center) is advance, ATDC (after top dead center) is retard. It might have something like "A/R" or even "Advance/Retard". It might help to take a rag with some gasoline or solvent on it and wipe off the indicator so you can see it.

Once you have the car idling and the distributor hold down loosened (don't remove it, just loosen it enough so you can turn the distributor,) point the timing light at the balancer and indicator plate, and rotate the distributor very gradually until the mark on the balancer starts lining up with the desired mark on the indicator plate. The marks in the picture I made only go up to 8 degrees, but yours are going to go a lot higher. Just set it to where you think it should be... 13 degrees, something like that, I'd say.

When you get it where you want it, hold the distributor still with one hand and tighten the hold down bolt with the other. Plug the vacuum line back in, adjust the idle speed if necessary (advancing the timing might make it idle a little higher,) have fun. :thumbsup:
 

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Sounds like your guy don't know sheit about carbs. A vacuum secandary carb only lets more are and fuel for what ever signal it gets. ie, little signal- little fuel, lot of signal-alot more fuel. Also if he locked down the rear barrels, you will never get WOT.
 

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Discussion Starter #18
Yeah I know he doesn't know sh*t about sh*t. I'm having someone else hopefully take care of my problems. Josh Keady helped me last night in determining that my choke is stuck. He said he thinks perhaps that the choke was taken off and the spring wasn't wound back inside the housing, cause my choke is just stuck open and it doesn't move when you push the pedal all the way down.
 
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