OK I am sorry if this is a stupid question but I am kind of at a brick wall

I have a 70 something 351w in my boat the problem I have is this I am trying to set the timing however do to the water cooling system I am unable to bring the vacuum advance around And am kind of stuck as the timing is so retarded that runs hot at ideal

 

Hook your advance to manifold insted of ported vaccum . That will advance it . Then bump down your timing as needed . a thought ?

 

dumb question what is the difference in manifold vacuum and ported and there would i get manifold from.

sorry i am spoiled by electronic engines

yonu

 

Manifold is engine vaccum . Ported is only supplied at throttle command through the carb . I would think you could find a vac port somewhere on the carb or intake that is full engine vaccum . Of corse vac varries with engine load . Wot = less vac ,part or closed throttle = more vac .

 

ok i will give that a look at tomorrow if i move the vacuum source should I expect any performance issues at WOT vs just above idle.

thanks,
yonu

 

There are threads about manifold vs ported . If set properly you can see better performance with manifold set up some say .

 

If his timing is retarded now, then you're taking him in the wrong direction. He just needs to reset the initial timing. to accomplish what he's trying to do.

 

If he hooks to manifold vac , that will advance his timing at idle . I got that he could not advance any more because of clerance issues with the coolant crossover assy between the exaust manifolds .

 

Then the simplest method is to jump all the wires around the cap one position each, by going clockwise with them all.

 

That may work , or be more than he needs . A thought worth considering though .

 

Done it a few times myself, it'll work. You're moving the wire positions 45 degrees without touching the distributor itself, you then can pull back what's needed by adjusting the distributor.