When the heads were rebuilt, did they surface them? A deep cut or several light cuts can leave the manifold mismatched to the vee formed by the heads. If you end up pulling the manifold, check for port matching. Look at the gaskets you remove and try to determine if they were sealing all around each port.
Nope - 80's Grand Cherokee with a Cadillac 502. That'll rattle your fillings...
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Been done. Original post, "and a new non points type HEI distributor and wires"
More correctly, Bias-belted
Transmission modulator?
on the
Found very
Steak brand
pushed on
bad years
bearings were
and ran well
a Innovate
afr, and far
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reinstalled
thread, the carb
okay, around
almost
I checked
propane check to
psi. on six
kinda low at 14
else looked
really well at
etc., and
satisfied for a
order. The
it, but I d
local garage
valves appeared
probable cause for
rebore
job, new
reground
a new Pro
and wires.
worse and
other
The cam
Compression is
installed.
more lift.
the timing
intake manifold
No real
secondary bores of
air leak
then dropped
The torque
bad, vac.
accessories are
owner is livid.
who owes what
healthy from a
Carb.may simply
the Edlebrock
don't think the
stock intake
anyway. I
time. None
engine. Any
It looks like you have already tried all the things that have been suggested by the guys responding except for one: The crankshaft vibration damper. The outer ring must have rotated slightly giving you late ignition timing. My vote goes with those that said that that was the problem......phil
add another vote for this, check the timing mark on the balancer. Is the pointer welded or bolted to the front of the motor, I've seen the wrong one installed on the bolt on type.
BTW, I've never seen or heard of a stock factory damper that was pinned, maybe a high performace aftermarket, but not an OEM. Thank You, Randy
Remove 333 from email address to reply.
on the
Hey there oldjag, there's a lot of guys waiting to hear what you came up with to fix this idle problem! Let us know, eih? please........phil
good call, Andy. Be sure to check that.
Yeah that's one of the concerns I have with the Q jet in this situation, it might be possible the power valve is opening slightly at idle. Won't be able to tell much more until the owner is able to work things out with the shop on payment and get the vehicle over for me to look at it further. We may order a Q jet master jetting kit that hopefully has the required parts to recalibrate the power valve and get the main circuits flowing right under load.
The shafts in the Q Jet carb that I last saw on the car are in good shape.
.
No EGR valve is in place. All vac lines were pulled off, and PCV checked and replaced with new. Damper was checked vs TDC when engine was apart and was supposedly okay.
The damper was checked vs actual TDC when the engine was apart, and was okay as per the engine builder, but when I get my hands on the car it will be rechecked.
e balancer and TDC =A0needs to be verified. Don't overlook
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Still waiting for the owner to get the car out of the shop where it is now, but the vac pull off is really something to be looked at. Plugs and wires are new, and a HEI dist. was installed, all vac lines were isolated, and propane checked were done, but as I noted that was done prior to the rebuild, so I'll probably need to go over a lot of things again.
Actually the bad idle was present for a long time prior to the side of the road failure, and ALL vac connections from the engine were blanked off. Balancer question is valid, but engine builder said it checked out okay. Obviously at this point I need to question everything, especially the basics.
Well, the owner is having the shop put the stock intake back on, as he does not want to pay for the Edlebrock or have a non-stock looking intake.
The heads were pretty straight, so only a few thou was removed. The shop working on it seems to think the intake gaskets were sealing to the heads, uniform pattern.etc., but who knows, until I see it again first hand I won't really know.
Nope, checked that.
I should have more of an update soon. The owner brought it over yesterday and I took it for a drive. First impression when I first heard it is that it has a lot more cam duration in it than what was thought. It idles fairly lumpy at what sounds like about 850 RPM in neutral and gets worse in gear, but does not sound like a miss. It's not loading up, and it pulls strongly from a stop. Feels quite a bit stronger than a stock '69 442 Auto should. Also knocks a fair amount on premium at high RPM, probably because they dialed in so much initial advance to make it idle smoother. When I get some time, this weekend maybe, I hope to see if we can tweak the Qjet for a little better idle by changing the power valve spring.
Another question is that Old's used a 45 degree valve lifter angle on some early 400's and a 39 degree bank angle on later engines. It's possible there was a mixup and it has the wrong cam for the specific block. To my knowledge it's the original engine in the car so it should be a 39 degree block with the correct cam for a 39 degree block. This can cause a hell of an idle problem as one bank is advanced and the other retarded but the engine will still run okay at higher speed.
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