Can someone tell me why my 4bbrls wont open when I push the pedal to the floor? I havent had them working since the day whe got my Firebird going after the motor swap.

 

The air valve (the thing on top that you can see) isn't supposed to open then. That should only open when the engine is under load.

If the throttles themsleves aren't opening, check the choke linkage.

 

Are you talking about both the primaries and the secondaries or just the secondaries? How do you know they're not opening?

 

is that so... i must have done something wrong when putting back my carb, the secondary will open when in neutral and revved by hand... sound wicked

 

Yep, you did something wrong. If it opens w/o load, it'll bog when you floor it with load.

Can you feel the secondaries open up? Yep, you're bogging...

 

Its just the secondaries because everytime you put a load on they dnt want to open. You can hear them open can you not?

 

Oh and its not the linkage because we checked that out and it was just outfited with a carb kit this year to so it should be good.

 

If you don't have an air cleaner on, you can hear them open. If you have the snorkel air cleaner on, it muffles it quite a bit.

To clarify: Are you looking at the air valve on the top of the secondaries, or the butterfly valves on the base plate? The base plate has a little lock-out lever that is pushed off by the choke high-idle cam when it is all the way down (the weight end of the cam down, that is). If the choke isn't going off all the way, or this weight isn't going all the way down, the lock-out will keep the secondaries from opening.

 

five7kid,
Can you explain that? You've said it before, and I'm not sure I understand it. I don't understand why being able to feel them open always means bog. Take my carb for example. I believe it has too slow a vacuum can and too little spring tension, but I'm not sure. I'm a rookie.

When I floor it from a 30+MPH roll, I feel a slight increase in acceleration, then a larger increase in acceleration about one second later. Would you define that as bog? Why? I would think that if you feel a burst of speed when the secondaries finally open, they should have been opening sooner (and possibly more slowly). When I floor it from idle, it's as if I turned the key off. Silence,. . . pop!, . . . stagger, . . . acceleration. I know that's a bog.
Thanks,
Homer

 

Can someone give a possible list of things that might be causing my secondaries to not open at all?

 

linkage

 

Is that it??? Just the linkage.

 

Homer I'm not 5.7 but.......

Your not supposed to feel the secondary circut kick in. It's supposed to transition smooth so as not to feel a sudden jerk and the car starts pulling hard. If you have a second or two delay you are bogging.

 

Can you explain exactly what is not opening? We've asked a couple of times.

 

My butterflies for my secondaries are not opening and the linkage is fine i just want to know what else might be causing this to happen. I really want my 4bbrls to open I am missing out on some serious power. Thanks for helpin me out.

 

Do they open if you turn the throttle all the way by hand when the car is off and the choke linkage is clear?

Is your transmission downshifting when you floor it?

 

I haven't tried that with my motor off and yes my tranny is downshifting when you put it to the floor.

 

Okay, let's try to get this straight.

With the engine warmed up and not running, take the air cleaner off. Open the secondary air valves by hand (the "butterflys" on the top), then open the throttle by hand - look down the secondary bores - are the bottom butterflys opening, yes or no?

If you can answer that question clearly, we may be able to go from there.

 

thanks i will give that a try tonight and let ya knw