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Discussion Starter · #1 ·
I bought a MSD dist kit and it has full adjustment for the advance curve.
What RPM does the advance need to begin and how much total ? I think the limit is 28* mechanical . It starts easily w/ 12*initial.
10.5 to 1 w/781 heads,427 with 279*/290* Crane cam , QJ on alum intake -maybe 3310 Holley later, Hedmans ,3.31 rears.mostly street cruiser.
I will add a 6AL box with the dist. install also.
All new and haven't got enough miles to put it thru the paces yet with the original point dist
 

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I would use the 20 degree bushing 16-18 initial and 36-38 total.
You want all this in around 3000 rpms

Dave
I assume the vacuum advance is not used ,or needed .
The factory QJ has no venturi vacuum port.I intended to plug it anyway
 

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run the black bushing,18 degrees i think,all in at 2500-3000 rpm,(look at chart cant remember springs off the top of my head!!)try 20 initial,and see if she pings,if so back initial up a little.Once you get this then work on vac advance,USE IT.(MANIFOLD VACUUM)youll probably have to change VA can,get your idle vacuum,lets assume its 12-13,id run napa vc1843,(its my favourite!!!!)what specific dizzy do you have and whats your idle vacuum,report back
 

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run the black bushing,18 degrees i think,all in at 2500-3000 rpm,(look at chart cant remember springs off the top of my head!!)try 20 initial,and see if she pings,if so back initial up a little.Once you get this then work on vac advance,USE IT.(MANIFOLD VACUUM)youll probably have to change VA can,get your idle vacuum,lets assume its 12-13,id run napa vc1843,(its my favourite!!!!)what specific dizzy do you have and whats your idle vacuum,report back
Dist. is part of a ready-to-dist. kit...has reluctor wheel like HEI . Current QJ only has a manifold vacuum port. Venturi vacuum makes more sense to me, to increase timing with throttle opening. Not with the car presently but will check vacuum and get back later
 

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ok,sounds like a msd 8360,I looked at my charts,try the heavy silver,light silver spring combo on initial set-up looks like it comes in around 2800ish,once you get that dialed in,we'll work on your vacuum advance,you can check around,but trust me run manifold vacuum!!!!!!!(with proper can of course)report your vacuum findings
 

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Dist. is part of a ready-to-dist. kit...has reluctor wheel like HEI . Current QJ only has a manifold vacuum port. Venturi vacuum makes more sense to me, to increase timing with throttle opening. Not with the car presently but will check vacuum and get back later
You don't want that. With additional throttle opening you get more cylinder filling (resulting in higher cylinder pressure). Higher pressures burn faster, requiring less, not more, ignition advance. Listen to the guys recommending manifold vacuum advance. They know what they're talking about.
 

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Some engines like ported, some like full time manifold vacuum. In any case, use the vac advance. Your engine will run better, and cooler.
 

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Discussion Starter · #9 ·
ok,sounds like a msd 8360,I looked at my charts,try the heavy silver,light silver spring combo on initial set-up looks like it comes in around 2800ish,once you get that dialed in,we'll work on your vacuum advance,you can check around,but trust me run manifold vacuum!!!!!!!(with proper can of course)report your vacuum findings
Vacuum at 15 but idle is still at 1100 because of low miles on new cam. Idle is almost smooth at this RPM
 

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try the above mentioned VA can,its a good start,you'll have to modify your housing slightly,the msd can that comes with dizzy is all in at 15,wont work for u,route new can to manifold vacuum,adjust idle,the above can starts at 3-5,all in at 9-11,7.5 dist.degrees ,should work for you,make sure you get initial/total timing set up first as mentioned above
 
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