I'm going to cry.....
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,606
Likes: 1
From: Las Cruces NM
Originally Posted by bobs77vet
...have you taken your distributor apart to ensure everything is working properly?
I haven't pulled the distro out again though. With the pertronix in there, there really isn't much too look at. Just the rotor, ignitor module and the magnet...not much else.
Oh, and a friend of mine has a 750cfm edelbrock carb on his '68 Firebird, so we're going to swap it in and see what happens. Obviously, it'll be pretty rich, but it should at least eliminate or confirm the carb as the problem.
Chris
Last edited by okinawa86vette; Nov 23, 2006 at 11:50 PM.
Race Director
Joined: Nov 2006
Posts: 13,258
Likes: 7,848
From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
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Cruise-In VIII Veteran
Hi guy's I am a pro. mech. are you sure your not leaking vacum through the intake manifold gask into the valley. sometimes these leaks can make a ticking noise. Are you useing the proper gasket for the type of intake your useing? If it runs fine for 30 or so miles then acts up did you try retorqueing the intake?
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,606
Likes: 1
From: Las Cruces NM
I'll try retorquing it again, but it didn't do anything with the problem when I was running the last set of heads. It's worth trying again this time.
The intake gaskets are what's recommended by the intake mftr.
Chris
The intake gaskets are what's recommended by the intake mftr.
Chris
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,606
Likes: 1
From: Las Cruces NM
Alright, I swapped carbs with my friend's Firebird.
His ran great with my carb and my car still ran the same. So it's not carb related.
Here's a thought....Could it be possible the intake manifold is cracked? It's a Weiand 8004 aluminum one.
Chris
His ran great with my carb and my car still ran the same. So it's not carb related.
Here's a thought....Could it be possible the intake manifold is cracked? It's a Weiand 8004 aluminum one.
Chris
Intermediate
Joined: Oct 2005
Posts: 43
Likes: 0
From: Yorktown VA
Chris - I have a 72 with the same problem - rebuilt engine with less than 1000 miles - new heads - comp cam - alum intake - eldenbrock carb. Radically pulsating vacuum readings at idle - steadies out when applying gas. I have changed out the alum intake for the stock and still have vacuum readings as you have described. I believe my problem is the seal between the heads and intake - sucking oil through the bottom of the seal into the runners - basically a vacuum leak - I have noticed that my intake gasket looks oil soaked at the edges. I will pull the heads to see if they have been decked/milled and see if that is causing the misalignment.
good luck
t2
good luck
t2
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Advanced
Joined: Sep 2006
Posts: 55
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From: Wellington
This is like my favorite TV show that shuts down for the summer... I wanna know what happens next!?!
Le Mans Master
Joined: Dec 2006
Posts: 8,837
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Well, I just read this whole thread for the first time. I had a similar problem once, so here goes my 2 cents. Bad lifter.
Works fine when oil is cool, but collapses when oil thins out. Common to all his symptoms. Can't wait to here what they find.
Works fine when oil is cool, but collapses when oil thins out. Common to all his symptoms. Can't wait to here what they find.
Instructor
Joined: Oct 2001
Posts: 224
Likes: 0
From: Austin TX
Im for leaking intake!! as I have had the same issue before. Upon having erratic vac. on all ports for so long I ended up replacing teh new Edelbrock intake with another and using Permatex Right Stuff sealer I found that the "old" intake was warped although maybe 2 thousanths was enough to not seal properly to the heads and caused all kinds of erratic problems from timing to A/F issues. I would take the intake off again and triple check the trueness of the intake. Also this stuff http://www.permatex.com/brand_right_stuff.htm saves lives...or nerves!!
-Nick
-Nick
