stumbly 351w please help

[67coupestang]

i searched and didnt come up with much, maybe i dont know how to phrase it. my 67 has a MAJOR stumble when the thottle is bipped hard off idle. i'm pretty sure its a vacuum leak but i cant find it. Its been on going for a while. ive replaced the carb base gaskets and the intake gaskets at least twice. i dont remember if its made any difference for a while or not, but its definately acting up now. is there something i could be doing wrong? aside from having the heads, block, and intake all squared up... also when i really pin it on the road it develops an oil spurt both out of the dipstick and oil vent cap on the passenger side im wondering if a lack of inital vacuum compiles when the throttle is wide open and the pcv system is affected, any input woiuld be great i'm a little embarassed when i go to acelerate and it pops and lags, its really taking some of the fun out of this car, some not all

 

[ForceFed70]

Sounds to me like classic symptoms of a problem with your accerator pump in the carb. I'd look iinto that. Might be time for a new diaphram, or to move up to a larger squirt.

 

[Texas 66]

Another item to check is the vacuum advance on the distributor. Will also produce the problem you are having. Ed

 

[67coupestang]

any thoughts on the oil geyser? its only rapid acclereration not only high rpm. im going ot pick up a vacucm guage after work today and see what i can find out. whats the best way to check the vacuum advance? maybe if i can find a vacuum pump/guage i'll pick that up

 

[oz]

Describe your PCV sustem. If you don't have sufficient vacuum to suck out the blow by, you'll push oil out. How many miles on the engine? When I friend of mine rebuilt his 351, he had to put pcv valves on both valve covers to keep it from pushing oil out for a few hundred miles - just until the rings were seated.

Do a leak down test to make sure your rings are good. Does it smoke?

 

[67coupestang]

well the motor has maybe 6k on it it doesnt burn oil, it smokes only when it seeps on to the headers then its a mess. my pcv is connected to the front port on my edelbrock drivers side holds the valve then the rear of the passenger side has the vent.

I picked up a mighty vac so i could do some diagnostics
I dont know how erratic is erratic but connected to the pcv port vacuum fluttered between 16-16.5 maybe 17, dropped to absoutley 0 when i bipped the throttle. so then i hooked it up to the vacuum advance on the distributor and gave it a few pumps, the guage didnt even move, obviously the advance isnt working if it cant hold a vacuum right.. but does that sound like the only problem? i wish i knew how to post a sound because it seriously has the choking suction sound when you pin it and the motor lags.

And about the oil problem... a buddy and i threw somethings back and forth at work today and all we came up with is blow-by (hope not, afformentioned mileage) or the angle of the engine. when i put the 5-speed in the tranny x-member from dark horse? dropped the engine quite a bit, on top of that the rear of my car has been dropped with reverse eye springs and the front is sag stock. so i'm wondering if during hard acceleration the oil is spilling out of the sump and into the rear of the pan and being wipped up by the crankcase, its kind of a stretch but better than bad rings dont you think? and damn all that windage could be costing my 1/4 mile times