msd mechanical advance question
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From: Perry Florida
yea the new timing set is sposed to be here today at 4, i got the one for a 95 f350(straight up double roller), and the little key for the balancer is good. would the timing chain being as loose as it is cause me to get false timing readings?, its got about 3 inches of slop in it.
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From: Perry Florida
ok i got the new timing set and all on now but it still runs weird. it will idle at 5-10 btdc but i seems to run a hell of a lot better at 18-30 btdc. so what could be possibly happening to cause this now? i got the timing set for a 95 f350, its a double roller straight up.
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Your truck was designed with a vacuum advance in mind. Is the engine stock otherwise? IE, are you running the stock cam with a Holley 4180?
I'd bet your idle circuit would need to be re-tuned to compensate for the ignition.
With the timing set at 8*, a vac advance would pull you up to 30, raise the idle and burn fuel a bit differently.
My bet is that the mixture is off at idle. Can you lock the timing at 8-10* and adjust the mixture?
I'd bet your idle circuit would need to be re-tuned to compensate for the ignition.
With the timing set at 8*, a vac advance would pull you up to 30, raise the idle and burn fuel a bit differently.
My bet is that the mixture is off at idle. Can you lock the timing at 8-10* and adjust the mixture?
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From: Virginia
On most Fords, the vacuum advance doesn't work at idle, since it's hooked to a ported vacuum source on the carb.
A engine will run fine with the vacuum advance disconnected, it's just used to improve engine efficiency at part throttle conditions(fuel mileage).
A engine will run fine with the vacuum advance disconnected, it's just used to improve engine efficiency at part throttle conditions(fuel mileage).
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His issues sounds like they're more than just timing though. If the timing is locked and true at 8-10* and he still has a bad idle, he should be looking elsewhere.
Could be EGR valve hanging open (if the truck still has one) or any number of carb issues.
Also, plugs, wires, cap, rotor could be suspect.
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From: Perry Florida
i have a big cam and a holley 4150 carb. also new ford racing 9mm wires msd distributer, box, coil all ignition is brand new
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From: Perry Florida
tomorow im going to do a compression test (what #s should i look for?) and replace the intake gasket and carb gaskets (maybe part of the problem?). but should i get the valley pan type gasket or the separate type? whats the difference and what are the pros and cons of each? also what are the tourqe specs and procedure for tourquing down the intake manifold? and should i use rtv on the intake gaskets?
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tomorow im going to do a compression test (what #s should i look for?) and replace the intake gasket and carb gaskets (maybe part of the problem?). but should i get the valley pan type gasket or the separate type? whats the difference and what are the pros and cons of each? also what are the tourqe specs and procedure for tourquing down the intake manifold? and should i use rtv on the intake gaskets?
The carb gasket could very well help, if it's currently leaking air.
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From: Perry Florida
i did spray a bunch of starting fluid around the manifold and carb gaskets with no changes but i also sprayed some straight in the carb and it didnt even effect anything by doing that. but i looked at the can and it didnt even have ether in the ingredients so i guess i got the cheap brand lol but could these gaskets even be causing these conditions?
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From: Virginia
If you use a metal pan gasket and want to use some sort of sealer around the air/fuel ports, you can use permatex type sealer.
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No harm done here... 
You've probably pulled a lot more intakes than I have. Last one I did I actually used gask-a-cinch to hold it in place while the intake went down.
Do the intake bolts on the 460 have blind holes that can leak oil like small block Chevies? (I haven't had the honor of pulling the intake on my 460 yet...)
You've probably pulled a lot more intakes than I have. Last one I did I actually used gask-a-cinch to hold it in place while the intake went down. Do the intake bolts on the 460 have blind holes that can leak oil like small block Chevies? (I haven't had the honor of pulling the intake on my 460 yet...)