69Vett

[QUOTE=Jebbysan;1594143005]That engine should be making about 13-14 in of vacuum.

Captain bob

i also agree with your vacuum estimate ,perhaps 20 due to **** building ability.like i said way,way beyond normal auto machine shop engine builder in this case totally useless like balance to 1/10 of a gram!!!!!!! even normal excepted practice like weight the rod and grind boss on bottom of rod to make all rods same weight---nope he find balance point and takes respective weight off both top and bottom of rod after placing in his own alinement jig. drill bottom of piston pin boss ----------nope he mounts on lathe and machines off respective weight.on and on and this engine will never see the track!

mikem350

Bring it back to engine builder, let him check vacuum with his equipment

zwede

I'd be very surprised if it has more than 14" of vacuum. At 750 rpm my guess is 10-12".

theandies

Have you tried a different vacuum gauge yet?

MelWff

In the first post in this thread the OP stated he tried another gauge

Captain bob

this is my procedure for tuning.i remove 1/8" id. hose from dizzy can and plug hose to can with golf tee, next i put hose from vacuum gauge directly on this 1/8" outlet on base plate of Holley performance carb .i test with engine warm up and choke off.this is how i tune idle needle valves in carb with aid of highest readings on vacuum gauge on each needle valve.then set mechanical advance of dizzy (36).raise rpm to 2500 and check total advance. when finish i remove tee plug dizzy back in to vacuum and check total advance (mechanical + vacuum) at 3000 rpm. am i doing something wrong? car will stumble on take off at WOT. unless you power brake to 2100 rpm. stall convertor is 2600 rpm with 700 R4 and 3.55 gears.

theandies

Sorry, I'm getting old. By the time I get to the bottom of reading all the replies I forget stuff.