Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribitor ??

stspinner

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Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribitor ??

Looking for some advive experience on camshaft selection and whats need to be donttrise the rev limiter on my stock ignition ? or replace the distribitor ?

Compression is good 148-152 PSI motor has about 350 hours on it, the main reason is I sold it to my friend and want to replace the head gaskets and have the heads magna fluxed/pressure tested . So the plan is to put a very small cam it with kit (springs/ retainer/ guides/valve job) looking at comp cams XM 256 cam 212/216 duration @.050" .447/.462 lift 112 degree lobe center or a crane cams Z 256 2 206/218 duration @ .050" .432/.459 112 degree lobe center,
Will be usingn the stock intake and exhaust with Quadra Jet carb.

Thanks !

Scott
 

Bondo

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Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

Looking for some advive experience on camshaft selection and whats need to be donttrise the rev limiter on my stock ignition ? or replace the distribitor ?

Compression is good 148-152 PSI motor has about 350 hours on it, the main reason is I sold it to my friend and want to replace the head gaskets and have the heads magna fluxed/pressure tested . So the plan is to put a very small cam it with kit (springs/ retainer/ guides/valve job) looking at comp cams XM 256 cam 212/216 duration @.050" .447/.462 lift 112 degree lobe center or a crane cams Z 256 2 206/218 duration @ .050" .432/.459 112 degree lobe center,
Will be usingn the stock intake and exhaust with Quadra Jet carb.

Thanks !

Scott

Huh,..??..??
Boat motors are rev limited by the Prop, not the ignition...

Either of those cams should be Ok....
 

stspinner

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Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

so there's no rev liniter on the stock OMC igintion ?
 

Howard Sterndrive

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Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

no rev limiter
 

stspinner

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Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

no rev limiter

My new boat has a rev limiter built into the ECU (5400 rpm) , how does my old OMC keep from over reving when the prop comes out of the water ?
 

bruceb58

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Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

how does my old OMC keep from over reving when the prop comes out of the water ?
Your hand on the throttle is the rev limiter.
 

stspinner

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Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

Your hand on the throttle is the rev limiter.

that's odd because your hand is not fast enought to stop engine damage, I read the omc manual and they do have a spark interuper 13 K posts and this the advice u give ??
 

bruceb58

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Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

that's odd because your hand is not fast enought to stop engine damage, I read the omc manual and they do have a spark interuper 13 K posts and this the advice u give ??
They absolutely do NOT have any thing that interrupts spark based on RPM. Which manual are you reading this in? Is it a factory manual for an 86 Cobra?

The spark interrupter you may see is the ESA which interrupts the spark while you shift.

There is no rev limiter...the only thing that is going to limit the RPM is your hand on the throttle as I correctly stated.
 

Bondo

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Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

Re: Winter Project Rebuilding 1986 5.7 L 260 HP Motor Camshaft & Ignition/ distribito

They absolutely do NOT have any thing that interrupts spark based on RPM. Which manual are you reading this in? Is it a factory manual for an 86 Cobra?

The spark interrupter you may see is the ESA which interrupts the spark while you shift.

There is no rev limiter...the only thing that is going to limit the RPM is your hand on the throttle as I correctly stated.

Ayuh,.... How did boat motors Ever survive, before the 'puters were added to save 'em,..?? :rolleyes:

that's odd because your hand is not fast enought to stop engine damage,

If yer hand ain't quick enough, ya fix what breaks...
 
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