steve
Thanks. i have read in the manual. guess it would help if i said why i was asking for this info.
back when i first got the engine running, i had set the mixture screws 2 turns down as the manual said. the manual also says to adjust to get the fastest idle after that but i got caught up in setting the timing and watching the engine temp so i never really did a lot of adjusting from there. the engine ran fine and idled fine so i was not in a hurry to try another change.
the engine temp had me wondering though. one thing that can affect the temp is running too lean. (my plugs were sure looking quite clean) So in an effort to help my temp concerns, i started to make the mixture richer. i adjusted out a little at a time until i felt the idle was really starting to suffer. then i adjusted back in one flat.
as a base line i had measured the distance to the jet from the bridge when i started (two turns down) and also made sure they pretty much matched from carb to carb. as i adjusted the carbs richer, i also pulled the tops and check the depth of each jet.
a lot of other things along the way but fast forward to this past week. my engine has been running cooler. because of some things i have done? maybe... but i think it has more to do with the engine parts starting to seat. in fact lately on longer runs the engine would run cooler at the end of the run than the beginning.
As i am now getting close to my 500 mile mark on this engine break-in, i thought maybe it was time to adjust the carbs back to where they probably should be. i knew i was running rich. even the plugs showed it now. So i ordered a colortune plug as an extra check for getting the correct mixture. i have never had much luck just lifting the piston and removing the brearthers is a real pain. on saturday i tried the colortune plug. i starting adjusting the mixture leaner until i was getting blue in the glass. i did a few plugs. balanced the carbs and used the colortune once more. the car idled much better, started great when it was warmed up and seemed pretty good on my test drive. maybe not quite as much punch on the accel side but it rev'd easy and ran fine. a couple miles from home, i glanced at the temp gauge. it was about 200. it has not run that hot for a while. when i shut it down, it went to almost 230. again not done that in a while. usually any more, it never runs over 195, usually 190 or a little less. and when i shut it down it might get to say 220. but that is it.
So my first thought was, running too lean? then i wondered, if after the two turns down, do most people have to go a flat or two more, maybe 3? I figured it was easier to ask if anyone knew how deep they set their jets. then i could compare easier.
my engine is still pretty new and maybe it needs to be a little rich to help offset the tightness. also i am running with my valve lash at .015. could the setting be letting less of a fuel mixture in on the cycle and causing some of the heat?
anyway, i was curious if anyone else had taken a measurement to see if maybe i should go a little richer than the colortune plug was showing me.
my engine has run pretty well at all these settings. it does not backfire, it does not miss, it does not hesitate. Just at the richer setting the idle was loping and it was harder to start if it was hot.
odd enough, the colortune plug had me back close to where i started with the two turns down. the depth was .064.... well except the back carb. to get the right color on those cylinders the depth was .035. Not sure why that is. ( i pulled the breather today and cleaned it to make sure it is not clogged with oil or anything since the vent goes in that breather.)
anyway, right now i have lowered the mixtures one more flat so the jets are at .071-.073 depth. i went ahead and set the rear carb to match the other two. i am thinking i will try this setting and see if the car runs any cooler. if not i may try another flat. where it is right now, the car still starts great when hot and idles smooth.
but i wondered if someone else had found, from experience, that everything works better at a certain setting for their engine.