5.3 Sleeper cam???
I have a stock 5.3 L33 and am looking at a cam change. I have researched this extensively via the internet and think that something like the Comp XR265Hr-15 (or alternative) 212/218 0.55/0.63 with a 115 LSA (there seems to be 2x versions of this cam, a High lift and Low lift).
It would seem to me that this would be a better option in terms of performance over the old standard of using an LS6 cam.
I will be using new springs and had planned to use PAC 1218's.
I do not want all out Power/Torque, I would just like an increase in the region of 20-30.
However the cost of using a aftermarket cam like the 212/218 with new springs compared to an LS6 cam and springs is quite a lot different.
I have a number of people refer to the 212/218 cam as 'the LS6 upgrade cam'.
I want to have road manners similar/same as stock but most importantly I need to make emissions testing and can't increase the power too much as the chassis will then struggle to put the power down hence why I only want 20-30
The engine is utilising a fully remappable Ecu.
The cost of getting my heads ported (they are 799's) v's a cam change is practically the same.
If anybody has any experience on a cam change in a 5.3 that is purely as a 'sleeper' cam I would be interested to hear their thoughts.
Thanks in advance.
Check out this car craft article. You will find a lot of answers there.
Also, is your car a manual or auto trans?

I should have added that I've already got an Ls6 intake and a ported Tb.
As I have the engine in bits I'd really like to change the cam now as it'd be a lot easier.
I saw the Carcraft article from this year 'Ultimate Ls cam test' and that's what steered me towards the 212/218.
The Ls6 doesn't perform brilliantly against the other stock cams but it is a cheap alternative.
Plus the engine is going in a car as opposed to a truck like the engine came from. I'd like to raise the Rpm slightly from the truck setup to around 6k.
Check out this car craft article. You will find a lot of answers there.
Also, is your car a manual or auto trans?
In answer to your question I'm running a manual 5 speed.
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http://www.ws6project.com/user_stor/...oducts_id=4626
Along with the Cam Motion #C33-676 , which is also a 212/218 113lsa+4, lift
.544"/.544"..
Both of these cam have -11* overlap.
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http://www.ws6project.com/user_stor/...oducts_id=4626
Along with the Cam Motion #C33-676 , which is also a 212/218 113lsa+4, lift
.544"/.544"..
Both of these cam have -11* overlap.
Looking at the data you supplied both of those cams are almost exactly the same except the extra lift on the Cam Motion cam. Would the latter cam be too close in lift for LS6 springs?
I presume that aside from the other differences in those cam the extra lift would yield some more power/torque?
You also mentioned that both cams have -11* overlap. Is that important and if so why?
I have read the 'Cam discussions' on here but a lot of it still has gone over my head.
Essentially I'd like to get a good bump in hp/torque but need to ensure I am able to have the engine mapped to emission testing requirements. Cam choices are such a difficult area for the novice.
Last edited by TableLeg; Sep 1, 2013 at 03:56 PM.
I have just looked at the LS9 cam,
Intake Duration at 050 inch Lift: 211
Exhaust Duration at 050 inch Lift: 230
Duration at 050 inch Lift: 211 int./230 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.562 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.562 in.
Valve Lift with Factory Rocker Arm Ratio: 0.562 int./0.562 exh.
Lobe Separation (degrees): 122.5
It seems lift is comparable to many of the other cams, Duration is different however at 211/230 as is the LSA at 122.5.
Can anybody please tell me what the likely effect of these differences would be over the other similar 212/218's with 113 to 115 LSA?
What effect would that have on the engine rpm? Like I say I would really like the RPM a bit higher at around 6200 rpm as opposed to 5500.
4.11 gears? Is this referring to the diff ratio or something else?
Headers I can see would be a benefit. Any particular type you would recommend?
I will probably have to use the block hugger 4 into 1 type due to body space restrictions.
http://www.ws6project.com/user_stor/...-lift-212-218/
http://www.ws6project.com/user_stor/...valve-springs/
I have just looked at the LS9 cam,
Intake Duration at 050 inch Lift: 211
Exhaust Duration at 050 inch Lift: 230
Duration at 050 inch Lift: 211 int./230 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.562 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.562 in.
Valve Lift with Factory Rocker Arm Ratio: 0.562 int./0.562 exh.
Lobe Separation (degrees): 122.5
It seems lift is comparable to many of the other cams, Duration is different however at 211/230 as is the LSA at 122.5.
Can anybody please tell me what the likely effect of these differences would be over the other similar 212/218's with 113 to 115 LSA?
http://www.ws6project.com/user_stor/...-lift-212-218/
http://www.ws6project.com/user_stor/...valve-springs/
I'll definitely consider the 220 as well but it also just occurred to me that I'd need some hardened pushrods wouldn't I as well. All extra cost.
Last edited by TableLeg; Sep 2, 2013 at 11:07 AM.







