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Who has them on there boats? and do they work well... I figured they are more for a car than a boat right?
?
Looking for a dizzy and all i can find are the vacuum advance style:|err
2sav
 

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Sit N' Spin
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Who has them on there boats? and do they work well... I figured they are more for a car than a boat right?
?
Looking for a dizzy and all i can find are the vacuum advance style:|err
2sav
You can use a dizzy with the vac advance dashpot...just dont hook it up to anything or remove it as it serves no real purpose in a jet boat. You figure a jet boat engine is at full advance by 3,000 RPMs and most jets don't ever run below 3,000 anyway.
 

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I was told to lock it out, if not it will move around on you. The lock out kit from petronics was b/o so I just tacked mine in place with a wire feed welder.
 

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Highaboosta
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The vacuum advance is to add additional advance past the centrifugal weights under high manifold vacuum and light load cruising speeds.

There's nothing wrong with a V/A dist but you need to know what manifold vacuum you are pulling at a cruise speed. If you have high manifold vacuum / light load you can get a benefit from the additional advance which may increase fuel economy.
If you have low vacuum / high load the V/A dist is not going to do anything for you.
Under low vacuum / high load it will have no effect and you will just be running off the centrifugal weights. For WOT operation you need to check timing with the V/A disconnected.
 

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Lurker
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The small gain in fuel mileage you may get with a vac. advance will be all but unmeasurable and the problems they can create (big increase in spark scatter) can get expensive depending on your combo. If you have to run a dist. set-up for it you definatly need to lock the advance plate with either the above mentioned kit or tack weld it.
No reason for one in a boat IMHO.
 

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There are quite a few mech advance Distributors available through summit or jegs. I use MSD in all my boats.

Cy
 

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How are the advance plates locked out ? Do i need to do this with a HEI dizzy in my jet ? The V A is plugged also. Do i need to readjust the timing after locking out the plates ? Sorry for all the questions. The motor runs great the way it is but like everybody else, i'm looking for more in little places.
 
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