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whats the purpose ? or is it just to fine tune to a specific engine ie. stroker long rod what? just kinda confused about it thats all.
 

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This is going to get good real fast.
Wags

OK, I will start with a general answer. Generally advancing the cam will help lower rpm range, while retarding it will help in the upper ranges. It will also affect piston to valve as it changes valve events with regards to the crankshaft.
 

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steelcomp was here
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Not much to add to those two answers.:)hand
 

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Generally speaking:

if your engine makes 550 hp at 6,000 and falls off past there ( assume cam is straight-up), retarding the cam will extend the rpm range a couple hundred rpms. Advancing the cam will allow the engine to make more hp and more trq at a lower rpm and falls off faster or sooner than running it straight-up.

S CP
 

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steelcomp was here
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Generally speaking:

if your engine makes 550 hp at 6,000 and falls off past there ( assume cam is straight-up), retarding the cam will extend the rpm range a couple hundred rpms. Advancing the cam will allow the engine to make more hp and more trq at a lower rpm and falls off faster or sooner than running it straight-up.

S CP
And why is that? :D
 

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whats the purpose ? or is it just to fine tune to a specific engine ie. stroker long rod what? just kinda confused about it thats all.
455 olds..v-drive w/40 gear 11 3/8 x16 dog ear
-4 ig. [email protected]*spun prop 3900 at the hit and pulled 5300 easily
0 [email protected]* spun prop 40-4050 at the hit and pulled 5300 but barely
+4 ig. tim. @ 36* spun prop 4400 at the hit and was all done @ 5200
added 2 more degrees ig. tim. 4475 (about) at the hit and was done @ 5200.
+4 is where i wanted to be with a 5K redline
 

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Resident Ford Nut
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455 olds..v-drive w/40 gear 11 3/8 x16 dog ear
-4 ig. [email protected]*spun prop 3900 at the hit and pulled 5300 easily
0 [email protected]* spun prop 40-4050 at the hit and pulled 5300 but barely
+4 ig. tim. @ 36* spun prop 4400 at the hit and was all done @ 5200
added 2 more degrees ig. tim. 4475 (about) at the hit and was done @ 5200.
+4 is where i wanted to be with a 5K redline

Did I miss something ? He asked about cam timing not ignition timing :)bulb

S CP :D
 

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Resident Ford Nut
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And why is that? :D

Something to do with cylinder psi and the starting of the intake event as compared to crank degree. I think :)bulb

S CP :D
 

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oh come on.

Advancing the camshaft tightens the " " piston to valve clearance.....while loosening
the ".....
Is that how them racer dudes set piston to valve clearance? :p:D

-4 = retarded ?

+ 4 = advanced ?

Just making sure.

Different engine combo's will behave differently.

S CP
Well....it is an olds........bet ya didn't know that the oil pump runs backwards from a chev?:)bulb..............:D:)devil
 

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Question? If you advance or retard the camshaft in the engine and it picks up power what does it tell you about the cam in the engine?
 
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