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been mucking around coz i was bored, its quite lonely here in the jungle. i have forever been stuck with a 3k carby on my 4k, which had to hav its idle (slow) jet cut with an angle grinder to allow enough fuel to flow for a decent idle, and also required that the idle mix screw be wound out one turn further than factory PLUS also needed a customized PCV valve which provided perfect seal and no leak at idle for it to run without mucking with the base idle speed. so i got to that point and realised that once hot, the engine would idle fine with the mixture screw back in abit, to half a turn from factory spec. so i decided i wanted economy and clean plugs and set the mixture to this lean condition and i was, up until now, living with the fact i had to rev the engine when cold to warm her up before going anywhere. this is very difficult when you don't have a handbrake and live on a hill in the jungle. so yesterday i decided to make a lever in the car which operates the idle mixrure screw from the drivers seat hahah. when cold, i push the lever forward to turn the screw anticlockwise half a turn, and then when its warmed up, i pull it back out and it idles slower and leaner where it should be. i feel carburettor cold starting systems shouldve been designed like this in the first place rather than choking the air intake and opening the throttle at the same time like all conventional chokes do. i think the convential choke plate does sweet fek all and everyone who uses one is being fooled by the throttle cold idle link. in effect, i am manually doing what EFI vehicles do, enriching the fuel for the warm up period.

Interesting reading. Its a thing of beauty.

Damm that looks good! The T pistons are like the 18RG's, so they don't propagate flame very well when cold or lean either. Its funny because hemispherical heads were the absolute peak of technology in the 50s and 60s, until they realised bathtubs were just miles better for just the reasons you mentioned.

What on earth. You do realise that the choke flap creates a smaller opening in the carby, which speeds up the air as it goes past the venturi which sucks in more fuel and richens up the mixture? The chroke flap does increase the fuel, automatically, just like an efi system.

If it was sludge jamming it you would know! It was thick like soot mixed with tar on that Holden! You couldn't touch anything under the cover without ending up smeared in black gunk that wouldn't wash off... For dry, sooted-up valve guides you can check first. That's what the compression test would tell you, if they were holding a valve open you would have zero psi on that cylinder. If you don't own a compression gauge, buy one, it will last you all your life. Anyway, check out Google on how to position the motor for doing tappets if what I write doesn't make sense. First, pull the plugs out. (or leave them out after your compression test) Basically you have two pairs of cylinders moving up and down together, #1 and #4 and cyls #2 and #3. So when #1 & #4 move up together, one is on compression stroke, one on exhaust stroke. (At the same time the pair of #2 and #3 are moving downwards.) You can watch the one on exhaust stroke as it closes the exhaust valve and opens the inlet valve. There is about 20deg of overlap, and when those two rockers are at an equal height the piston will be on top dead center. Luckily you can check your estimation by looking at the timing mark on the crank pulley TDC mark which is for #1 and #4. So you watch the cylinder on exhaust stroke to get TDC, then set the sister-cylinder which is on compression. That will have maximum tappet gap on both valves, which should be 10thou for inlets and 12thou for exhausts. (bigger gap on exhausts because they get hotter and the stem expands more) Lets say #1 was on exhaust and you set #4. The firing order is 1-3-4-2 and you had #1 on exhaust. So the next cylinder on exhaust is #3, and you watch that until the inlet just starts down as the exhaust closes, and set the tappets on #2. After watching #3 cross, you are back to setting the #1 and #4 pair. This time watch #4 until it crosses over and set #1, again you can check TDC by looking at the crank pulley. Then do the same for the last cylinder, watching #2 for the valves crossing and setting #3. I undo all the locknuts at the start, so I know I've done a rocker if the nut is tight. Don't go too stupid doing them up, and leave the ring spanner on the nut as you turn the bolt with the screwdriver, as the gap will change as you tighten the nut even if you hold the screwdriver steady. Just back the nut off a tad until you can alter the gap with the screwdriver and do the nut up again. Some take a few tries to get a feeler gauge sliding through smootly. What are you planning for the car?? In other words... how soon are you pulling the head off for modifications??