#1  
Old 07-20-2015, 06:57 AM
68ragtop's Avatar
68ragtop 68ragtop is offline
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Join Date: Jan 2002
Location: Green Bay, Wisconsin
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Bob, I know you had your carb gone through, but was it setup for the camshaft you installed? I only ask because When I broke in the cam on my 68 GTO engine, I used the carb from my 78 Trans am because I knew that car ran perfect & I didn't want to add a possible carb issue to the mix during the 68's cam break in cycle. On that engine I am running the 068 cam. first thing I noticed was I had to open up the throttle blades quite a bit to get the 68's engine to idle from where it was at on the T/A

I had the 68's original carb rebuilt by a local carb expert & he wanted all the specs of the engine. When I got the carb back from him & installed it on the GTO's engine, I couldn't believe how much smoooooother it idled. Not just a little bit, but a lot! Still had some lump to the idle, but very controlled. Next time I saw the carb guy I asked him what was up with that & he told me quadrajets are very, very sensitive to vacuum & have a touchy idle circuit. Because I added a cam that had less vacuum, I add to open the throttle blades to allow more air to get into the engine for it to idle. If I remember correctly this puts the throttle blades in a bad spot and causes some sort of fuel drip from the main circuit, or maybe it was too much from the idle circuit? (i forgot which it was) but it was loading up & he said no adjustment would fix it. So he made small holes in the throttle blades to pass more air & allow the blades to be in the location they were supposed to be. What a difference that made.

I'm guessing you have all of this covered already in your carb rebuild, but thought it was worth mentioning because I learned a lot from that experience. My carb guy said its one of the reasons people who modify their engines toss the quadrajets to the curb & call them junk.

Car looks fantastic! BTW, my 78 survivor I'll bet has more scratches & dings than your car has. In fact, when I first bought the car, I almost repainted it. Soooo glad I didn't now. So few of these cars out there with original paint.

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68 GTO 4-spd Convertible
78 S/E Trans am L78, WS6 Auto
78 S/E Trans am W72, WS6 Auto
79 10th aniv W72 Trans am
80 Indy pace car Trans am
89 Trans am GTA
  #2  
Old 07-20-2015, 07:41 AM
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Bentwheelbob Bentwheelbob is offline
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The carb is fine and the car idles nicely. Cliff supplied the deluxe rebuild kit spec'd for the precise application and motor/car details. It may just be the that EFE is tired since it is the original. It holds vacuum when bench tested, but flutters and rattles at low rpm.

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