Thermoquad tuning on 318
I will try raising the fuel level
To make sure I am understanding correctly, some transfer slot exposure at idle is desirable? Doesn't this mean I want less initial timing?
Ok sounds good.
1)I didn't say to raise the fuel level! It may already be correct!, Only change it if it is not correct,
2) absolutely yes the transfer slot should be exposed to be looking about square under the blades. and adjusted like that, the mixture screws should be about 2.5 turns out.
#) For highest vacuum, your engine will want idle timing of about 25 degrees.
With the T-slot synced up, obviously the rpm will be outta sight, and the trans is gonna BANG! pretty hard when selecting a gear; so you can't run it like that.
Since you cannot optimize the Idle-timing anyway, then you can run whatever Idle timing the engine will not bang the trans at and still not have the dreaded tip-in sag. Beyond that, the engine does not care what the Idle timing is.
If the engine is stock, you should always start your IDLE-tune, with T-slots synced and factory timing, which, on a stock 318 with a 2bbl carb was always zero to 5 degrees. Once the Tip-in sag is gone, THEN you can increase the timing. But if the Idle-rpm climbs too high then it will bang the trans. So you gotta find a happy medium.
Now; that happy medium will change with the Convertor stall. The higher the stall, the less it will bang. but; the higher the stall, the less important the lowspeed timing is. So if your convertor is stock, with a stock cam and compression engine you may have a 1700 stall, which means if the Idle becomes too powerful, because of extra timing, then the engine will be tugging to go all the time. Having to sit on the brake pedal All the time, gets old in a hurry. Whereas if you had a true 3000 stall, you could almost run the timing locked right out. So again, Idle-timing is a compromise.
The only good reason for a streeter to run a lot of Idle timing, is if the distributor has a straight slow timing curve and no vacuum advance. In this case, if you don't run the numbers then the low-rpm power gets sluggish.
Over the years I've been here, (not that many)
@Mattax has published a lot of timing curves and a lot of smart advice.
But in a DD or rice burner, there are better ways of waking up the low-rpm power, than excessive Idle-timing.
In your case, with a stock convertor, a true 12* at 550/600 rpm in gear, is, IMO, already borderline too much Idle-timing.
Btw, I once had a manual trans 292/292/108 cammed 11/1 Scr 367, that would pull itself, with correctly synced T-slots, along at 550 rpm with the timing pulled down to 5 measly degrees of advance. I still have this combo minus that cam, but now with a 230/237/110 cam that will do the same thing, down to 500 rpm.
The point is this; once the Wet fuel-level, to T-slot, to mixture-screw setting are right, the engine does not need a lot of Idle-timing; AND the earlier your intake valves closes, the less Idle-timing she will want.
In your case the stock cam is advertised as 240/248/110 and installed straight up the Ica is just 50*. That is a pretty small number.
Performance street cams run in the range of 60 to 68/70 or so, and a weekend warrior might run up to the mid 70s, possibly a lil more. Each bigger cam will like a lil more idle-timing, but it's also gonna like a lil more stall.