I cant get my new engine to run smooth. Seems untunable.

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Ricko1966

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He says he's only pulling 6 inches of vacuum at idle,it's a bunch more than a worn throttle shaft. He says he's sprayed the whole top side looking for vac leaks which is why I'm trying to get him to check for vacuum in the crankcase like maybe he has a vacuum in to the lifter gallery.
 

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Never mind...
 

AyWoSch Motors

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What I told you to do would take less than 5 minutes,and then we could rule out intake gaskets. I actually don't even think it would take 5 minutes.
I'll defiantly try it out
 

AyWoSch Motors

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Easy way of telling if you got a vacuum leak in the intake Valley is to stick a propane torch in were the pcv valve goes put your thumb over the pcv valve. It will idle up if you got a leak in there even if its a small one.
Dont have a torch
 

Originalthor

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Well shucks. Just talking to the father inlaw this morning having coffee and he's a mechanic and its to bad you don't have a torch cause it would say alot quick.

He did mention though that if its a tbi carb intakes that he has ran into using those carb plate engines lifts points it can pull the intake gasket apart cause there flex in the aluminum. I can't remember if you used one or did the corner to corner chain.
 

AyWoSch Motors

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Well shucks. Just talking to the father inlaw this morning having coffee and he's a mechanic and its to bad you don't have a torch cause it would say alot quick.

He did mention though that if its a tbi carb intakes that he has ran into using those carb plate engines lifts points it can pull the intake gasket apart cause there flex in the aluminum. I can't remember if you used one or did the corner to corner chain.
I used a chain across the block from head to head..

Its an 85 TPI block and heads, with an edlebrock intake, and q-jet carb
 

AyWoSch Motors

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Well I finally solved this probelm.
Brand new edlebrock AVS2 later, and its runs perfectly. Super smooth. Idles happy at about 500 when warm. Running better than ever, im super happy..
Just experimenting, i turned the idle way down, and got it to run at about 100 rpm. Barely registered on my tach, still sounded smooth
 

AyWoSch Motors

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It was defiantly the old rochester. After getting it off, it seems that the throttle shaft wobbles around alot.
 

AyWoSch Motors

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Don't toss it. Have it rebuilt.
Not my rochester actually, was just a loaner from my buddy to see if it would run better than the old eddy. Thats his problem now.

Although i have a cabinet with 5 rochesters tha need rebuilding, that i plan on keeping and redoing.
Was at the flea market a while back and i got an extra long old metal milk crate, with 4 quadrajets, an old rochester "4 jet", 2 "2 jet", and an edlebrock air cleaner for $50 bucks. Steal...
Then my boss gave me another 2 q-jets for Christmas.
So far ive used 2. The one i put on my K20 was good, but the other i put on my corvette, and the gasket was all ripped, kept having issues.

They're good carbs, i have no complaints, just all mine need fixing.
 

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Big Ray

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between 3-5 hundred bucks. That's dipped, bushed, jetted and adjusted to your application, refinished and looking like new.
 

AyWoSch Motors

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between 3-5 hundred bucks. That's dipped, bushed, jetted and adjusted to your application, refinished and looking like new.
Oh okay.

A new Edlebrock is about $4-450, so...
Haha
 

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