Hello guys. to change stock cams with gsc s2 cams @ evo ix Degreeing the engine is a Must do? it is a necessary procedure?

 

Just install them like you would factory cams. Line up the timing marks and you're good.

 

I've read that the GSCs are made pretty well and don't need to be degreed, unlike BC (and such) that are a couple of degrees out. That's the benefit of a billet cam.

 

Correct, as others mentioned they will be fine to install straight up. Also not for nothing but I dont think you would be able to even degree them with the motor still in the car.

 

All aftermarket cams, billet or non billet, require to be zeroed. Billet is a form of creating a camshaft, a piston, a compressor wheel, instead of casting the part, and it has nothing to do with zeroing them. The stock markings are for stock cams. Any aftermarket cam, with different LC, LSA, nose, flank and ramp, needs to be zeroed according to the card's specs which accompanies them.


You can fit certain cams on the stock markings but you will never know how advanced they are.


You need to firstly zero the cams, and if you wish to move the adjustable pulleys to the stock markings because that's the dialing in combo that suits you best in regards to what you are after from your setup, that is something else. You do need a pair of adjustable pulleys with any aftermarket set of cams, in order to zero it, and be able to dial them in on the right combo for your demands.


One can also degree a set of cams with the engine installed on the car, a bit more difficult than with the engine out, but nothing that cannot be done.







Marios

 

^^^Well said @Evo8cy

 

I'm not gonna argue that It wouldn't be good to verify the cams match the card, but It's not required. Unless we are going to argue what the definition of required is.

 

It is required, if one wishes to extract the best outcome of his setup for his intended purpose of it.
It is required if one wishes to get the best dynamic compression and V.E out of his setup.
It is required if one wishes to rev higher than the stock rev limit without risking to plant a valve on a piston when he dials in the cams at a specific combo, especially if either the head, or block or both have been resurfaced.


The card is not there just to verify it, it is there for one to be able to zero the camshafts according to their specs, without the card one does not know for instance the degrees at which the adjustable pulleys need to move in order to bring the cams at zero.






Marios

 

Yah sure, but its not required. All the things you mention require work in addition to, its not like simply degreeing the cam is going to accomplish any of what you listed.

 

"Can" it improve things? Sure. Is worth the hours of time to make 2-3% more power when you can just turn the boost up a smidge more? No.

Also, if the cam is far enough off to cause piston to valve contact, an adjustable gear isn't going to save you and this issue will come up when you spin the motor over to check timing.

 

No it is required and it is going to achieve saving your engine, if it already has a resurfaced head, block, or both, and if you are using an 11,2mm cam set which you have left at stock markings, but you are 8 or more degrees advanced instead i.e.


All the things I have listed will be done to a modified setup nevertheless, otherwise what's the point of using a more aggressive aftermarket cam set if you maintain the stock rev limit, what's the point of losing 15-20% of their total power-gains, by allowing the cams to function at stock markings.


In other words, it is an absolute requirement to zero the cams to save your engine under certain conditions, and it is a non absolute requirement to dial them in if you do not wish to extract the max gains out of them.


As I said previously you may get away with leaving some milder sets of cams at stock markings, engine safety wise, but it is not the optimum thing to do, you leave enough power gains at the table.




Yes it is, by simply zeroing and degreeing the camshafts for max gains, the car will be mapped giving out the desired powerband and max gains for the specific setup.










Marios

 

You are wrong, by degreeing the camshafts one can see 15% gains at least close to 20% max, depending on setup and fuel. One gets to maximize the V.E and dynamic compression, of the engine and makes more power at the same boost. Been there done that.



You are wrong again, someone who degrees camshafts without zeroing them, using the stock markings that is, will see nothing of a problem when he turns an engine by hand, or even at idle, or at lower rpm. But when the engine is spinning at 8, 9,10K and the camshaft is too far advanced the risk of touching a valve to a piston is far greater, especially if the valve springs is a tired/worn set. He will only see the problem when turning by hand, if the cause of it, is too much resurfacing of the head and block, in this case the pulleys can do nothing as it is now a matter of space and wrong engine building.








Marios

 

Piston to valve clearance has to be checked. Simply degreeing the cams doesn't guaranty anything. Cams come with a certian amount of advance ground into them and a card that tells you what thats suppose to be. Degreeing them simply means measuring to verify they match the card. If you want to dial the cam in for best performance for your setup that requires dyno time and experimenting with different amounts of advance etc. The further off the card the cams are the more important degreeing the cam is to get it true to what its specs should be. Machining a part from a billet is far more precise then from a casting so you don't see as much variance in this higher quality part.

Again, its a good thing to do, trust but verify. To the topic of this thread though, in this situation, its not required.

 

Man if only I'd degreed my cams, I could be over 650whp on my 57lb/min turbo! How silly of me to forget by degreeing cams you can literally defy physics...

Absolutely not required. Especially for the S2 grind.

 

Tell yah what, next time I have my engine on a stand (hopefully later then sooner) I'll degree my S2's and see how they compare to the card. Then I will update this post with the results. Just to establish some facts though, I am running S2's straight up in OEM gears. I am spinning higher then the factory RPM limit. I am making more power then I was with OEM or HKS 276/278 cams. I have had my head reground. OEM valves w/ upgraded springs/retainers.