Well thanks to everybody who responded. Here's what's up so far;
The carbs are freshly rebuilt - nothing wrong with them although I did NOT
replace the jets or the float needles. The floats are fine and the jets are
in good shape IMO. BTW, the vacuum on the HIF's came off the manifold and
the HS4's off the carb right after the throttle plate.
Went back to check on the timing AGAIN and the points gap AGAIN, checked
compression (120 lbs. across all four - not good, especially for a HC
engine, but consistent), found one vacuum leak (intake manifold plug - fixed
it), took everything back to ground zero and retuned to another nice idle
and as soon as I got out the drive it STILL ran like shit. Started
backfiring to an embarrassing level. Took it back in and started over.
I noticed that when I'd rev it up to 2.5k to clear it for a minute it would
stay there for about 20 seconds and then slowly start to fade back down to
1k or less without my having moved the throttle. I'm starting to believe
myself it's something other than the exhaust , but I'm damned if I can
figure what it is. At the end of the evening I pulled the diz to take it
inside and pulled it apart. I did notice the top plate wasn't sliding around
very well so I took it all apart, cleaned it up and put it all back together
again. Maybe, just MAYBE that was it. It did kind of act like the advance
wasn't advancing or to be more precise the retard wasn't unretarding.
The upshot is; I could tune it so it revved fine through the range, but as
soon as I put a load on the engine it acted like a virgin at a frat party
("You want me to WHAT??!!) Now all I can get is backfire anytime I rev it.
I'm about to put the old beatup exhaust back on just as a control if the
dizzy work doesn't.
Todd, I'll have to check, but I bought the system as a 1 7/8" OVERSIZE. I
just went out back to check and OD on BOTH systems is 1 13/16", taken right
before the front silencer position. So ID on both would be about 1 3/4", or
what I thought was factory.
Glenn "Maxima driver" Schnittke
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No one in Tuna knows what I do for a living.
Why should they care what I say?
Glenn Schnittke Recovering Musician
Nashville TN 615-385-2800
schnittke@mindspring.com
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