looking for advice
 

hi from a newbie,
(i also posted this in 66/67 lemans forum and i apologize for doubling up but after lurking around here for a couple weeks it seems there are some VERY knowledgeable folks.)

yesterday i was driving and had to turn around so i stopped, hit reverse, and when i grabbed first again the car started missing and bucking so bad i had to have it towed home.

here's what i know:

2 hours and about 20 miles before trouble started i checked inspected plugs and gaps-good
i put ten gals of 93 in
it had not so much as hiccupped lately
fuel pump working-don't know pressure
it's got a holley 650
it starts well but idles rough
i checked one cyl for spark-should i check them all?
both float chambers getting fuel
the accelerator pumps are porting fuel properly but when actuated the engine starts to die----too much fuel?

fuel filter not clogged
vacuum lines intact
NO backfiring
it's a 66 lemans WP block, which leads me to my other question. did any WP blocks have 4 barrel intakes? or were they all with 2GC'S.

today i'm gonna check timing, check compression and pull the rotor and inspect and check points and i want to troubleshoot as thoroughly as i can before i swap carbs out of sheer frustration. it was on my list but not this soon.

thanks for your time, patience and especially your help.

joe

Maybe a float needle problem, causing flooding? Sometimes you can see this with it idling and air cleaner off- looking down carb throat, you might see fuel "dribbling" in. Sometimes a light rap with a small hammer on the needle area of the carb will get the needle to seat.

A Holley 650 carb on an (assumed 326 cid) engine should be a great match. What intake is on the engine. Cast iron stock afb type 4 barrel with an adaptor? A Q-Jet 67 up intake with the 650 carb being a spread bore design?

Need a list number off the carb and more engine intake data.

The list number will be have a # and then 4 numbers located
on the air horn of the carb.

Tom V.

Welcome to the forums! I agree on the needle thing. I had a similar problem with my race car out at Norwalk. Needle wasn't seating properly, and it was dumping fuel dwon the secondaries...ran like poop...eventually not at all. Tore carb down to clean and inspect. Installed new needle and seat and all was right with the world. Just something to check.

If you were fairly aggressive with the stop, back, forward routine, I wonder if the carb float may have jammed open. StrAnger things have happened. I have had floats stick just from turning the carb upside down before installing. Or a piece of crud could have sloshed up into the needle and seat. crud is a technical term for dirt.

I agree with all the above posts. I now have a good spare(same model/spec's) Holley carb so all i have to do is swap them for quick elimination process. I think they come with time released dirt and malfunctions ;)