28 pwks

[dirtclod20]

I have my mods in my signature, but with pro circuits and twin pwks. I installed 28PWK's 135mains, JJH needles, 38 pilot and it only runs with the air screw 3 turns out and with the chokes up. Is the next step going up to a 40 or 42 pilot? It revs fine once it's on the needle, but when it goes down low it's no good. Should i turn the idle screws all the way in and back them out equal amounts, because they just turn and turn and I can't make it run any better with one thumb on the throttle and one playing with the screws? Thanks

 

Marcus

Edited April 13, 2009 by dirtclod20

[burleybanshee]

I would say everytyhing is to small. 135 mains, might be close but i would go up 145 with a passion port job and do plug chop. Your idle jets should be up at 42 maybe higher. You can't go by the average jet size of the 34-35 size carbs, the 28 pwk and 30 oko run a bigger idle jet than its bigger brothers. I had 30's and switched to 35, didn't change anything else and had to run a small idle jet.

 

Get your idle figured out then play with your main, that will let you set your neddle correctly for the mid throttle after you figure out your wot/main jet.

[shanYE west]

where these carbs new or used?

[rtcc]

thats confusing though because when you screw the air screws out you are leaning them out and 3 turns is max. So you have gone as lean as you can with those pilots but then you are running with the chokes on, so it cancels it out.

 

 

I run 38 pilots in my 28pwk's but they are still a little fat on the bottom.

 

I need to find a better needle I think too.

[dragbanshee]

Sounds like it would be really lean, I wouldn't think I would be to far off in ele. than you, and I run 50 pilots & 160 mains. Warming up now, so I will lean it out a little 45-48 and 155 mains.....Indiana, and running pods, sorry, didn't see what you were running.

[dirtclod20]

these were used carbs from lobo on the board. Right now I have no air filters because I'm missing part of my airbox that meets the carbs. I'm probably going with some pods whenever I get them ordered. I may be able to turn the screws back in and get it sounding a little better. I haven't been in the carb turning game for a while. I guess you can tell :-)

 

Marcus

[dirtclod20]

these were used carbs from lobo on the board. Right now I have no air filters because I'm missing part of my airbox that meets the carbs. I'm probably going with some pods whenever I get them ordered. I may be able to turn the screws back in and get it sounding a little better. I haven't been in the carb turning game for a while. I guess you can tell :-)

 

Marcus

 

So I got it running and idleing most of the time, it's still spits a little on the low side, but messing with the air screws properly should help. Even with it tuned all wack it still has stronger pull then with 2:1/ptr mids. Which is good.