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Any preference to degreeing in a cam on a BBC in a jet boat? I figured I would just go 0 "straight up" with my offset bushing but Im just curious as to how most of us are setting theres up? My motor set up is a 427, Tunnel Ram Intake with 2 Holley 450cfm carbs. Camshaft is a Comp Cams 11-240-4 extreme marine and im running a gear drive. Is it better to go advanced some? Im not looking to race or anything, just wanna sound good & run good. Thanks for anyones input on this.
 

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Any preference to degreeing in a cam on a BBC in a jet boat? I figured I would just go 0 "straight up" with my offset bushing but Im just curious as to how most of us are setting theres up? My motor set up is a 427, Tunnel Ram Intake with 2 Holley 450cfm carbs. Camshaft is a Comp Cams 11-240-4 extreme marine and im running a gear drive. Is it better to go advanced some? Im not looking to race or anything, just wanna sound good & run good. Thanks for anyones input on this.
Set cam at 4degrees advanced.
 

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Any preference to degreeing in a cam on a BBC in a jet boat? I figured I would just go 0 "straight up" with my offset bushing but Im just curious as to how most of us are setting theres up? My motor set up is a 427, Tunnel Ram Intake with 2 Holley 450cfm carbs. Camshaft is a Comp Cams 11-240-4 extreme marine and im running a gear drive. Is it better to go advanced some? Im not looking to race or anything, just wanna sound good & run good. Thanks for anyones input on this.
If memory serves some Comps are already advanced , might check with them
COMP Cams® - Sorry...
 

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Put the cam in straight up and try it! No offense but you don't give enough info for a proper opinion! As in induction hull weight impeller cut and intended use! Buying an off the shelf cam is a crap shoot. All I can say is run it and see how it performs! If it's lazy on the bottom, advance it a pinch, if it is hard on the bottom and lays down on the top, retard a pinch. Good luck!!!
 

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Never fails!!! info coming up as I am typing! With the specs on that cam I would probably retard 2 degrees to start.
 

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Are you actually checking it Daniel?

You have to put a degree wheel on it. The mix of cam pin, timing set etc will more than likely not put it where you think you are.

It's extremely rare for me to find one exactly where it should be by the install.

And you verify the timing marks on the balancer and pointer while the wheel is still on it.
 

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Discussion Starter #10
Thanks for the input. The hull is a 87 Youngblood Picklefork, not sure what the weight is or which impeller is in it. Im running a Weiand Tunnel Ram with 2 Holley 450cfm carbs. 1970 BBC Oval Port Heads and a 1969 427 Engine
 

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Discussion Starter #11
My neighbor races dirt cars and he has a degree wheel so i am gonna have him help me out with degreeing it in correctly.
 

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Thanks for the input. The hull is a 87 Youngblood Picklefork, not sure what the weight is or which impeller is in it. Im running a Weiand Tunnel Ram with 2 Holley 450cfm carbs. 1970 BBC Oval Port Heads and a 1969 427 Engine
I will stick with advising 2 degrees retard with the heads and carb set up. The oval ports will need a little help on the top end. Buy themselves they will produce enough bottom end! Changing cam timing is an easy fix in the boat! Try it and go!!! Good luck!!!!!!
 

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Discussion Starter #13
I will stick with advising 2 degrees retard with the heads and carb set up. The oval ports will need a little help on the top end. Buy themselves they will produce enough bottom end! Changing cam timing is an easy fix in the boat! Try it and go!!! Good luck!!!!!!
👍
 

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Bostick Racing Engines
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Are you actually checking it Daniel?

You have to put a degree wheel on it. The mix of cam pin, timing set etc will more than likely not put it where you think you are.

It's extremely rare for me to find one exactly where it should be by the install.

And you verify the timing marks on the balancer and pointer while the wheel is still on it.
X2!

Put wheel on it and see where you actually are. Just randomly throwing a +4, +2, -8, x64, /3, whatever bushing is just about as good as guessing how many fingers I'm holding up right now. Personally, I'd degree it and make sure it is where the cam mfg actually wants all the timing events to occur... if you were to exactly know what all you have going on there... then playing around with timing events may be beneficial... but, seeing as you haven't listed any details such as compression, impeller, etc... best bet is go with where it was ground to and go with it.
 

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X2!

Put wheel on it and see where you actually are. Just randomly throwing a +4, +2, -8, x64, /3, whatever bushing is just about as good as guessing how many fingers I'm holding up right now. Personally, I'd degree it and make sure it is where the cam mfg actually wants all the timing events to occur... if you were to exactly know what all you have going on there... then playing around with timing events may be beneficial... but, seeing as you haven't listed any details such as compression, impeller, etc... best bet is go with where it was ground to and go with it.
hil:)
He could shove it in blind folded and manage to hit one of the recommendations on this thread



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Discussion Starter #16
Thanks everyone. Ill call Comp Cams on monday and see what they suggest. Worst case ill go straight up with it and try it out. Pending its results ill retard or advance some.
Thanks again. 🏁
 

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Bostick Racing Engines
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Thanks everyone. Ill call Comp Cams on monday and see what they suggest. Worst case ill go straight up with it and try it out. Pending its results ill retard or advance some.
Thanks again. 

Best plan thus far... :thumb:

But... I'd still stick a degree wheel on it to achieve what they recommend or "straight up" if that is the route you choose. Sticking a "0" bushing in it seldom achieves actual "straight up" when checked against a proper degree wheel... especially with a gear drive (assuming you're running a dual idler style). I've actually seen them where they were a full tooth off just lining the dots up "straight up" when using some of the cheaper brand dual idler gear sets.

(Not that I ever like to use the damn things... but that is a whole other threat that involves a whole mess of reasons why not to use them)
 

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Put a degree wheel on it. I installed a cam in a tow van once by just lining up the dots and it ran like shit. Decided to pull it apart and check the cam. it was ground 8* off.

it ran so much better once installed correctly
 

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As was posted, install it as per the manufacture....Without a dyno you might be able to tell the difference between +4* and -4*.....but to change timing you need to know where zero is in the first place.
 

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Best plan thus far... :thumb:

But... I'd still stick a degree wheel on it to achieve what they recommend or "straight up" if that is the route you choose. Sticking a "0" bushing in it seldom achieves actual "straight up" when checked against a proper degree wheel... especially with a gear drive (assuming you're running a dual idler style). I've actually seen them where they were a full tooth off just lining the dots up "straight up" when using some of the cheaper brand dual idler gear sets.

(Not that I ever like to use the damn things... but that is a whole other threat that involves a whole mess of reasons why not to use them)
I've had to re-mark timing sets also. It's amazing the junk available.
 
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