My friend is putting a decent motor together with a lot of the regular stuff to go right into the tens. The cam is a 212-214 roller, the cam card calls for it to be installed at 111. Just wondering if we put it in at say 108 or 109 will throttle response be better and will it hurt the top end.
What degree should I put my cam in at?
- Thread starter wrs2570
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turbofabricator
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- Mar 7, 2004
Install it per the cam card. Retarding a cam can HELP throttle response on some cams, and hurt on others, as is true with advancing the cam. The cam lobe designer is the best person to ask about the effects of advancing or retarding a cam. If the cam is ground advanced, then leave it straight up. This is why you should degree a cam in. Clear a mud, huh?:biggrin:
The relationship between the machining of the timing sprocket holes and lobes will be different from cam to cam, so yeah, it is best to degree a cam. I think its comp cams or crane that usually grinds all their cams 4 degrees advanced. When the chain stretches over time, then the cam will end up roughly straight up. If you dont have the means to degree it with offset keys and all the tooling, you will usually get decent luck just throwing it in straight up. Ive seen major losses in power advancing or retarding 4 degrees, even when done with proper tools. The rocker arm assembly is a total joke on these engines. The stamped steel holes for the shafts are usually really worn out and you use alot of lift. If I ever were to change cams, I wouldnt think twice about going with roller rockers and maybe even a roller cam. if money werent an object, Its the obvious choice.
Blown&Injected
Active Member
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- May 31, 2001
I have long ago asked WHY?
Why degree a cam? Everybody says "it has to be done if you want it right." But almost nobody can explain what happens if it is "not right."
The people at several machine shops (including a machine shop that nobody would complain about if they knew who uses them for their machine work) say just line up the dots - it won't make any difference on a street/strip engine. Lots of racers that build their own engines say the same thing, and in several big Pontiac and Ford engines that I know have had just a cam degree change with no other changes yielded no noticeable difference.
Degreeing a cam does not provide more or less power - the relationship of the lobes is fixed and unless it is WAY OFF and creating pumping issues with regard to the pistons fighting WRONG valve timing, all that is going on is that the RPM range the cam works in is moved SLIGHTLY one way or the other.
If I recall correctly 1* retarded moves the RPM range about 50 RPMS higher. Same power but instead of 2,000 to 5,500 RPM's, the cam now works best from 2,050 to 5,550 RPM's - BFD (big deal
)
But it does look like some mysterious sensitive type work that is not well understood so one may look impressive while putting an engine together
Why degree a cam? Everybody says "it has to be done if you want it right." But almost nobody can explain what happens if it is "not right."
The people at several machine shops (including a machine shop that nobody would complain about if they knew who uses them for their machine work) say just line up the dots - it won't make any difference on a street/strip engine. Lots of racers that build their own engines say the same thing, and in several big Pontiac and Ford engines that I know have had just a cam degree change with no other changes yielded no noticeable difference.
Degreeing a cam does not provide more or less power - the relationship of the lobes is fixed and unless it is WAY OFF and creating pumping issues with regard to the pistons fighting WRONG valve timing, all that is going on is that the RPM range the cam works in is moved SLIGHTLY one way or the other.
If I recall correctly 1* retarded moves the RPM range about 50 RPMS higher. Same power but instead of 2,000 to 5,500 RPM's, the cam now works best from 2,050 to 5,550 RPM's - BFD (big deal
)But it does look like some mysterious sensitive type work that is not well understood so one may look impressive while putting an engine together
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well said, I have kept this issue to myself due to the controversial nature of the opinions on this. personally if the cam is lined up I've yet to see a cam that does not meet the spec on the cam card.
I find the drgree wheel a waste of time unless your looking for a problem or you want to check a custom grind to make sure it's in your specs.
turbofabricator
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- Mar 7, 2004
True in most cases. BUT! A friend had a billet roller sent for a stock block and, and after trying for DAYS to get it to run on more than two cylinders, he found that they sent him a StageII camshaft. It was pretty challenging for him to figure out. I walked him through it on the phone. The cam company GLADLY exchanged the cam, though, once they realized it was their mistake. I also had a dbl. roller set come out of the box with no timing mark on the cam gear. So, I always check everything, as well as I can, BEFORE I turn the ignition key. Details pay for themselves in truck loads. An ounce of prevention.............:biggrin:
Thats why I left the unless....lol
but 99% of the time, you wont need it on a mild build, check your cam card, make sure the part number matches, and if you have an issue have someone degree it. it's easy to do but as shown you need a dial indicator and of course the wheel. and it can be intimidating to the novice.
but 99% of the time, you wont need it on a mild build, check your cam card, make sure the part number matches, and if you have an issue have someone degree it. it's easy to do but as shown you need a dial indicator and of course the wheel. and it can be intimidating to the novice.
For $100 in tools and a half hour of your time degree checking your camshaft is always cheap insurance. It's not that you will make tons more HP but it could save you 1000's of $$"s if some valvetrain parts collide when you go to start that new engine. Just because the part # is correct doesnt mean that part was machined properly!!!! You could be that 1 in 1000 then i bet you will degree every motor you ever build after that.:wink:
Lee Thompson
New Member
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- May 24, 2001
bingo!!!!
You should also measure as to how much clearance you have between rod and cam lobe. You could put it in without degreeing and have .005 clearance and never know it untill you start looking for the ticking noise. IMO .060 is min.
You should also measure as to how much clearance you have between rod and cam lobe. You could put it in without degreeing and have .005 clearance and never know it untill you start looking for the ticking noise. IMO .060 is min.
turbofabricator
Well-Known Member
- Joined
- Mar 7, 2004
True, especially on a stroker motor. Never had a problem with a stock stroke engine, but DID have an interferance on two stageII engines. Also recheck the clearance if you go from stageII heads back to GN1'a or vis versa!!! cam lobe placement is different on the two cams. (ask me how I know this? .....ever seen a timing chain BREAK? )
.....ever seen a timing chain BREAK? )Blown&Injected
Active Member
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- May 31, 2001
I bet nearly everybody that does degree a cam only looks at the #1 intake and the degree procedure does not have one checking the rod interference but damn man - I did not know there was a possible issue there - thanks for the FYI. Something else to check
The only time I have known rods to hit a cam was after something else had gone very bad. Sounds like there is a story in some of these posts
The only time I have known rods to hit a cam was after something else had gone very bad. Sounds like there is a story in some of these posts
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