Secondaries not activate when WOT, why?ٍ
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,877
Likes: 13
From: Doha
St. Jude Donor '08
Secondaries not activate when WOT, why?ٍ
My carb was working excellently before I took my engine apart for a full rebuild (well, it was done by Lars, so it must be good 
), but when I finished everything and put it back again, I've noticed that the secondaries will not open at all and also I feel a slight hesitation when I step on it. All in all, I feel that my engine is little chocked and don't give me the power that I was expecting, I feel that I shouldn't touch the carb adjustments because it was already tunes and was working fine before the build, what could cause that?
), but when I finished everything and put it back again, I've noticed that the secondaries will not open at all and also I feel a slight hesitation when I step on it. All in all, I feel that my engine is little chocked and don't give me the power that I was expecting, I feel that I shouldn't touch the carb adjustments because it was already tunes and was working fine before the build, what could cause that?
Drifting
Joined: Dec 2002
Posts: 1,946
Likes: 28
From: Long Beach CA
What carburetor are you running? Holleys and Q-Jets with vacuum secondaries will not open the upper secondary plates if you're sitting in the driveway blipping the throttle by hand. The only way to check is to put the car on a dyno and run it at WOT that way.
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,877
Likes: 13
From: Doha
St. Jude Donor '08
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,877
Likes: 13
From: Doha
St. Jude Donor '08
I'm using the original quadrajet. Yeah I took the car out and tried to step on it and I cant feel the secondries at all! , before that when I step on gas and secodires open, I feel the car will jump over and my head will hit the headrest hard!
Instructor
Joined: Feb 2006
Posts: 240
Likes: 0
From: Allentown PA
On a Holley you can use the paper clip trick to see if they're opening. Not in the driveway ofcourse, you need to take it for a test run with a load on it. Don't the Rottenchesters have a little 3" vacuum hose to the secondaries that was visible?, might be a leak there.
Le Mans Master
Joined: Nov 2008
Posts: 5,691
Likes: 12
From: columbus oh
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
You might have a vacuum problem. Vacuum doesn't activate the secondaries...but it allows them to open. Or, if you put in carpeting and heat insulation and/or sound deadener...you can't open the secondaries very far because the carpet is too thick! Have someone else push the accel to the floor [engine OFF] while you watch to see if the throttle plate is opening all the way (or not).
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Instructor
Joined: Mar 2007
Posts: 110
Likes: 1
I had a problem with my secondaries a couple of years ago, Would not open no matter how hard i put my foot into it, turned out to be a screw in the airhorn next to the secondary plate was tightened to hard and "mushroomed" the aluminum, binding the plate.
a little "filin' and i had my quadrajet roar again, Something to look at.
a little "filin' and i had my quadrajet roar again, Something to look at.
Safety Car
Joined: Feb 1999
Posts: 4,043
Likes: 342
From: Central NJ
The paper clib should be placed to the vacuum secondary diapram arm just under the base of the diapharm. When the secondaries open then that arm will move up, thus moving the paper clip down further on the arm.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
