It runs fairly well other than being rich, idle is really bad burns your eyes out in a matter of minutes even with the garage doors open.
Hopefully just a good cleaning and readjustment helps it out.
Badaboom! That tells the story. Every time I hear that, you can bet money that the throttles at idle are too far up on the Transfer slots, Probably because you are trying to run too much idle timing. IDK
234/244/112 is a big cam for a low pressure engine, and she's gonna want a good amount of bypass air.
That cam will idle, I guarantee it, right down to 8* advance, after you get your Transfer slots synced to the mixture screws to the closed throttle. And if it stalls at 5*, it's only cuz the engine is waaaaaaay down on cylinder pressure.
So
one more time,
for a non-4-corner idle carb;
Start the engine and set the Idle-timing to 14* Shut it off.
remove the carb, put it on curb idle, flip it upside down,
set the transfer slot exposure to a little taller than wide. BOTH sides the same! Close the secondaries up tight but not sticking. Flip it rightside up, reset the mixture screws to 3/4 turn out; then reinstall it.
Run the PCV to the primary side on the supplied nipple.
Run the Booster hose to the plenum on the firewall side. Do not run it to a single intake runner. If you have to, install a nipple into the plenum, but if it's a dualplane with a divider right there, drill deep, lol
If you have a 10.5PV, install it.
Now;
After this,
DO NOT touch the speed screw.
Ok start it up, and let her warm up, set the WET fuel levels.
Set the Idle rpm with Idle-timing to ~650 in gear.
Check for a tip-in sag. Looking for NONE. (See note-1)
Check the Rpm drop going into gear. looking for not more than 150rpm
Check for how badly the trans bangs on the N>in gear shift.
Check for the tell-tale tailpipe stink.
As for the TP stink, IDK if you can ever get quite rid of it. But I got darn close by drilling ONE hole in EACH primary throttle blade, about 3/32 inch. I put it on the T-slot side, between it and the Idle port, and I set it back from the edge centered about 1.4 inch from the edge. I chamfered the holes both sides. I recommend to start with 5/64ths and upsize by 64ths no bigger than 7/64 Take it slow. If you drill too big the idle speed will go up too far, and you will have to RETARD the timing, leave the doggone speed screw alone.
Roadtest it. I don't care what the Idle-timing is (see note-2), just roadtest the low-speed circuit for now. After you get back from the first test with 5/64ths holes, twiddle the mixture screws for best lean idle.
If the engine like more than 3/4 turn; adjust the
speedscrew 1/2 turn faster and try the mixture screws at 1/2 turn.
If the engine likes less than 3/4 turn; adjust the Speedscrew 1/2 turn slower, and try the mixture screws back at 1/2 turn.
I bet you are thinking that the mixture screws are for setting the idle mixture right? Well you are but, since they never shut off, you are also trimming the entire low speed circuit. So then, you want those mixture screws set as close to 1/2 turn as possible and still have the car be drivable. As before, you set the Idlespeed with timing.
Finally, roadtest the car for like a dozen driving cycles, before you think about the next size of bypass hole.
Note-1
If you get a tip-in sag, it's because the transfers are lazy. Most likely;
the fuel level is low, or
2) she wants a lil more throttle opening from the speedscrew. Readjust the mixture screws down to 1/2 turn out, and add a half a turn of Speedscrew atta time, until it goes away, but not more than two turns. Readjust the idle-speed with timing as may be necessary.
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What we are trying to do here is to get rid of the sag. and we want the mixture screws to remain as lean as possible. At Idle, you can make the engine run at any combination of transfer fuel to mixture screw, except maybe 100% mixture. But it will only run best within a very narrow window, and I try to make it so, with the mixture screws lean, cuz that will keep the plugs happy while cruizing.
Mainjets and PVs have nothing to do with the low-speed circuit, which circuit should get you to in the window of 35/40 mph. You want to be lean from idle to when the main picks up, because, I'm guessing like 90% of the engine's life, timewise, is gonna be on this low-speed circuit transitioning to the mains. If it's wrong, you'll be forever cranky. When it's right, the more right it is, the more you will like to drive there.
Note-2
Your Automatic-equipped engine does not much care about Idle-timing, so shooting for 20 degrees cuz some magazine said to, is, IMO, pure nonsense.
The First time the engine cares is at Stall-rpm, and the second time is at WOT after ~3500rpm. So those are your two targets. Everything else is more or less up for grabs.
What I mean is for your single stage timing advance curve, to hit the two targets of stall and WOT/3500, sometimes the curve just has to go thru 16>20 at idle, to connect them.
That's just wrong. Install a two stage curve that satisfies your engine.
