vacuum read out at distributor 85 Gwag

[letank]

i have been chasing greemlin... on the 85 Gwag project

what is the vacuum reading at the distributor at idle, engine warm..... i have the dum "non linear valve"....

it should be 0 or close to that, but i can read as high as 14.... which throw off the timing and idle speed,

cheers

Michel

[joe]

Yeah it should be pretty low at idle with the eng warm. When the eng is cold the CTO sends manifold vac to the dist to adv the timing to smooth the warm up a bit. Once the eng gets to 165* or so though it switches to ported vac. Seems to me the CTO isn't switching the vac over when it should. Possible it's just plumbed incorrectly?

[carrotman]

Try a different port off your carb with your vacuum gauge. Should read 0 at idle and about 5 inches right off idle. Called ported vacuum if you have a diagram.

[letank]

yes i have all the CTO's working correctly... i heat up all my fingers last nite

then it is the non linear valve.... i read about 2 at the carb ported vacuum nipple.....

thank you

Michel