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Discussion Starter · #1 ·
I am setting up my MSD dizzy and wanted to make sure I am thinking correctly. It comes with the two heavy silver springs installed and the blue 21 degrees bushing installed.

I was going to change to the two light silver springs which will have my advance all in by what appears to be 2900 RPM's, according to what I can see on the MSD advance curve chart?

Then I was going to change to the Silver bushing for the advance stop, which is 25 degrees...

So about 9 degrees with the springs and 25 degrees with the advance stop ....all in at 34 degrees on my 10 to 1 compression BBF 460 @ 2900 RMPS?

ISKY CAM - IRON heads - rewarder headers, full roller motor
 

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bring all the timing in by 2500 that way it will run nice and clean when your just cruzzing around and play with the total when i was running a ford it seemed to like allot of timing
 

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I am setting up my MSD dizzy and wanted to make sure I am thinking correctly. It comes with the two heavy silver springs installed and the blue 21 degrees bushing installed.

I was going to change to the two light silver springs which will have my advance all in by what appears to be 2900 RPM's, according to what I can see on the MSD advance curve chart?

Then I was going to change to the Silver bushing for the advance stop, which is 25 degrees...

So about 9 degrees with the springs and 25 degrees with the advance stop ....all in at 34 degrees on my 10 to 1 compression BBF 460 @ 2900 RMPS?

ISKY CAM - IRON heads - rewarder headers, full roller motor
You got the right idea, however with the light springs you may get an erronious reading trying to set base timing , my advise is to set total timing with your desired advance bushing and let base timing fall where it wants to. Depending on your idle speed the springs may already be advancing a bit. I would suggest one light silver and one blue spring, you may have less timing fluxuations at idle, especially if you have a lumpy cam.
-Josh
 

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run the black stop with the light springs, however the varibles of production equipent is not always the same. the mentioned lock the dist is the way it;s already there. However if you get it too high you will work the starter to death, then you will have to buy a start retard box, more money. I have one of my boats with the dizzy locked out works like a champ. My 460 I removed the dizzy and replaced with a 2 wire HEI works like a champ.
 

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Bring the timing as quickly as possible.

If you're stopping the total @ 34, your leaving power on the table with Iron Heads.

Turtle's engine has ported Iron Heads. It is run between 38 and 40 degrees.

JMHO. :D

RR
 

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Discussion Starter · #10 ·
Bring the timing as quickly as possible.

If you're stopping the total @ 34, your leaving power on the table with Iron Heads.

Turtle's engine has ported Iron Heads. It is run between 38 and 40 degrees.

JMHO. :D

RR
Mine are straight up Iron heads....1978's or very close to that.....and yes I have flat top pistons.... Previous owner said it was 10 1/2 to 1

38 to 40 seems like a lot? The reason I was aiming for 34 was because I thought I read somewhere people were running 460's and 34 to 36 was the sweet spot?
 

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Mine are straight up Iron heads....1978's or very close to that.....and yes I have flat top pistons.... Previous owner said it was 10 1/2 to 1

38 to 40 seems like a lot? The reason I was aiming for 34 was because I thought I read somewhere people were running 460's and 34 to 36 was the sweet spot?
I dought you got 78 heads on your engine look just below the valve cover in between the exhaust ports and tell us what numbers and letters ther is in order cause flat tops and D3 heads is only 9.5-1
 

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I would lock it out at 34* and bet you wouldnt see much gain if any if you added more timing you do have flat tops rite what year iron heads
Mine are straight up Iron heads....1978's or very close to that.....and yes I have flat top pistons.... Previous owner said it was 10 1/2 to 1

38 to 40 seems like a lot? The reason I was aiming for 34 was because I thought I read somewhere people were running 460's and 34 to 36 was the sweet spot?

Remember :)bulb, you're not dealing with Yates Fast Burn Chambers with Ford Iron Heads. If I set Turtle's engine up at 34, It'd lose at least 150 rpm(we've tried).

You said "Full Roller" to I assumed you had all the matching items in your build. IF you do, you're leaving power on the table at 34 degrees with Iron Heads.

That's all I have to say. It's your's, so you can run it as you see fit.

RR

PS. If it was an FE, it'd be between 38 and 42 to be right with Iron Heads, FYI.
 

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If you are running pump gas start with 34 and if all is well you can bump it up. The benifits of a locked out dist out weigh timing curves of which there seems to be hundreds. I have tryed all and gone nuts to figure which was the best. When locked out all you choose what is the best all out timing. Suggestion go light and move up and see the change if any. Remember all gas is not equal,, there all many variables as to true octane with additives, go slowly so as not to burn up the motor.
 

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I am setting up my MSD dizzy and wanted to make sure I am thinking correctly. It comes with the two heavy silver springs installed and the blue 21 degrees bushing installed.

I was going to change to the two light silver springs which will have my advance all in by what appears to be 2900 RPM's, according to what I can see on the MSD advance curve chart?

Then I was going to change to the Silver bushing for the advance stop, which is 25 degrees...

So about 9 degrees with the springs and 25 degrees with the advance stop ....all in at 34 degrees on my 10 to 1 compression BBF 460 @ 2900 RMPS?

ISKY CAM - IRON heads - rewarder headers, full roller motor
Since there is verry little "mid-range" load on a jet-boat engine, Ford OR Chevy, you might as well run as fast a curve as you can, you are not going to have loaded, high-advance, low RPM situation happen.

Set enough spring in it to stabalize the advance to not move at idle, then, as light a spring set as you can run.

My 454 is set up the second-lightest setup it has, the advance begins 1200/1300 rpm or so, is all in arround 25090r5pm, against the 25* stop, 10* initial.
My idle is between 800 & 900, so couldn't set it any softer.
 

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Discussion Starter · #17 ·
I dought you got 78 heads on your engine look just below the valve cover in between the exhaust ports and tell us what numbers and letters ther is in order cause flat tops and D3 heads is only 9.5-1
You know what they about assumption and I was making one about my compression.... my heads are stamped D3V2-A2A ...... just noticed I have Ford SVO roller rockers that are stamped with C351 1.73
 
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