So the gxp is in the shop for a ton of basic maintenance. Right before i brought it in it started making a crazy engine noise. I have a feeling it was in the valvetrain.
While it is in the shop being torn apart i am putting the headers on and Replacing the cat with a straight pipe. I was thinking of boring the engine out and putting forged internals on. After doing a lot of research and talking to a few companies, its not worth the 2 grand it would cost for MAYBE 20hp gains. So i scrapped that idea but i have a new plan

I am going to put a new cam in it. I am going way more aggressive. Any suggestions on the most aggressive cam i could fit in it? Keep in mind DOD was ditched a long time ago.
I am going big boys, time to see what this engine can do!

 

Spray that ******. Just make sure ya go wet so you don't grenade it!

 

From the people that I have talked to and what Ive read AFAIK the MAX lift is .605 IIRC. If Im wrong please correct me as Im looking for the same info. I was looking into the GM ASA cam but the lift is a little low for me but I like the duration which should work real good w/ these heads valve sizing.

 

i cant really find a clear answer as to what the maximum can be in these cars.

 

looks like your going to find out for us

 

dammit lol i was afraid of that

 

Sell me your rockers if you buy a cam!

 

Something in the 230/240 duration, .600 lift and 108 lobe sep should make you happy. Take your pic. Anything over .600 lift you should use roller rockers or your valve guide start to wear quickly from all the side load. Honestly you could check the truck forums or maybe something made for a C5 Z06.... shouldn't be TOO much different as far as power band characteristics.

 

I vote for a custom grind.

 

I am def doing a custom grind cam. I am probably going to use a 232/240/117 cam.
Here is the problem. We can not bore out the engine without MASSIVE cost. The aluminum block has steel sleeves. We can bore the sleeves a little bit but its not worth it. And an actual bore would be, like i said, EXTREMELY expensive.
After talking to a few people i found out a stroker kit my be the way to go instead. Here is the problem though. Our crank is shortened so no one makes that crank. People can make them but so far its like 2600 for a stroker kit, not including rods and pistons.
Unless i can find a way to do the stroker kit in an affordable way, i am just doing a cam, and forged internals.

After doing some more research, maybe grinding down a ls1 stroker kit is the way to go. Still researching it though.

 

by 117 do you mean lobe sep? If so, do you realize you won't make as much power compared to a tighter lobe sep and you won't have a choppy idle? If you're looking for a sleeper cam lingenfelter makes some nice ones.

 

You don't need a big *** cam, and if you plan on keeping your car a daily driver, then I really hope you think things out! It is far better to under cam then to over cam. You have a very good set up, and with headers you should be over 320fwhp. Didn't you learn your lesson with the big heads?
If you really wanna go big, then plan for some 3.69 gears and another higher stall converter. More compression will be needed as well. I would look into some new injectors, LS6 maf and a ported polished dbw truck style tb. Your going to need tuning so you might as well swap that stuff out.
If this was my project, then I'd swap that cam for a tr 220/220 112 and a crane cams, double roller hex adjust chain, crane 1.7 gold race rockers and add the LS6 MAF, with the tb mentioned above. You would also have to use a larger air filter too, due to the LS6 MAF's larger opening. There are many LS1's making over 400whp with the tr 220 cam. YOU DONT NEED A DUAL PATTERN CAM!!!!! the LS6 cam has a very wide LSA 118-119 and over 10 degrees of extra exhaust duration@.050 with .550" lift. The tr 220 will kick its but!! Dual pattern cams are for restrictive heads and exhaust. Definitely call around and get some more info and really think about were this car spends most of it's time. If your bottom end is shot, then get a LS2 block and adapter plate, re use your crank and figure it out. Good luck and please......... don't over cam trust me!

 

Great article on a 5.3 build and should be easy to duplicate!
http://www.superchevy.com/technical/...o_testing.html

And another
http://www.carcraft.com/techarticles...ine/index.html

Remember though, you will have to shift about 500rpm higher then the peak hp numbers and you will need a stall with about 1200 rpm less the peak torque rpm

 

You gave me some good Ideas David!!

 

Why Cranes rockers are superior:
http://www.vincihiperformance.com/RO...ON%20PAGE.HTML

Reason to use the Crane cams timing set

LSX SERIES ENGINE CAM RETAINER PLATE WEAR PROBLEM
We have noticed a considerable wear pattern on the front of the camshaft retainer plate, on the all of LSX series engines, including LS1, LS6, LQ4 etc trucks and on the new LS2 engines, as well. We believe this is due to improper oiling, between the plate and the timing gear. (see picture 1). This wear occurs with stock cams and after market cams as well, as it is a manufacturing defect not an aftermarket products defect. We have observed this wear on all of the LSX series engines with as little as 500 miles on them. VHP is bringing this information to our readers attention in hopes of preventing a serious engine failure. We have seen a material build up on magnetic oil pan drain plugs which, in some part, is due to the cam plate wear. We highly recommend using the Crane hex-adjust timing set on all cam installs, part number 144984-1. The bearing at the rear of the cam gear prevents most incidence of wear from re-occurring . (see picture 2). Here at VHP we have been notching the retainer plates for better oiling, to minimize this problem. (See picture 3). Upon tear down of test engines notching the plate and utilizing the Crane timing set has alleviated the problem.

I'd swap out your oil pump, for a LS6 ported pump, since you don't need the H.V anymore due to the DOD delete. H.V oil pumps costs HP.

TR 220/220 cam in mild 5.3 LOOK AT THE TORQUE CURVE! FLAT..............!!
http://performancetrucks.net/forums/...d.php?t=438267

TR 220/220 cam in another 5.3L Torque curve still FLAT!
http://www.thunderracing.com/dynogra...TB_iframe=true

TR 220/220 cam in a screaming 5.3L truck. Look at his 1/4 times. Flat torque cure AGAIN!
http://www.ls1truck.com/forums/dynod...-3-dyno-s.html

I could go on for days... and have done lots of research.
Keep in mind that our crankshaft balancer/pulley is a big time HP/TQ killer. It's extremely massive so we're always going to be handicapped! Also, these cams were installed and dyno'd in trucks with heavy driveshafts and axles with big tires, so the numbers might be a little lower then what you'd get.
I know Mix, has a bigger cam.. but it's really not needed. Again look at the tq curves. The tr 220/220 112 pulls to 6700!

Your cam specs with Cam Doctor
Duration@.050: 205* intake, 219* exhaust
Lift: 0.551 intake, 0.549 exhaust
LSA: 117.4

TR 220-112" - 220*/220* .551/.551 112 LSA
This cam opens the valves up a lot quicker then the LS6 cam. and although not recommended, you could always use 1.8 rockers. .583/.583 VS. .551/.551 It all really depends on your cyl heads flow numbers. I know the LS6 heads stop flowing more cfm, at around .550". With our smaller valves it might be a little less.

 

using that low of a lobe angle 112* with a big cam will cause the car not to idle. Also, like i said i am not trying to just make more power, i am trying to push the envelope. I can probally go a little lower in the angle, maybe 115* but any lower and i wont be streetable.
I already put down almost 320hp.....
And by 117 i mean angle, i am not trying to make it a sleeper. I want lope but i need it to idle at a light.

 

If you want lope but need it to idle you should stay around 114. Something in the 220's and .550-.600 lift should make you very happy.

 

The 220/220 cam I mentioned earlier is a pretty big cam compared to what you have now, but it's not as big as what you were wanting. A wider lobe separation with a lot of duration will push your power bang way beyond what your LS6 intake can flow. This is why I provided you with dyno results. I think you have already pushed the envelope, and you have really made a lot of us jealous, but really man.. I strongly suggest you think about your usable power band. At least take your car down the strip (and don't stop till you get a 2.0 60ft time) Before wanting more. You already have a stroked motor why would you want to stroke more? Maybe it's time to go turbo? Think about it..

 

Might be the best advice, since you keep wanting to add more power. Everything else you've done will support the turbo except the headers, and I'm sure that your shop can modify them to work with the turbo kit. You could also look at a universal turbo. You're LS6 cam will be fine. By going turbo you are effectively adding displacement, so you can skip the stroker kit, cam change, labor, etc. and just add power. With forged internals, you can make as much power as you can build a transmission to handle.

Almost everyone you talk to will give you different cam advice, but for your goals I'd recommend taking a look at the Stage 2 cam from Livernois Motorsports. Stage 1 will run good but won't push the envelope, and Stage 2R will have real trouble idling well.

http://www.livernoismotorsports.com/...6%3A+Camshafts

New Era also has some cams in the ballpark. These caught my eye, and since you switched to dual springs you should be able to handle the lift with no trouble.

http://www.neweraperformanceparts.co...EPSShtcamGTO|0
http://www.neweraperformanceparts.co...&PKV=SSTQGTO|0

Those are just some suggestions, and you can get a custom grind with similar numbers.

By the way, a dual grind isn't just about adding more exhaust duration to overcome a weak exhaust (and it helps more with a good exhaust), it's about the fact that the cylinder is pressurized when the exhaust valve opens. It's always been air in/power out, and there has been a lot of focus on intake lobe design (and intake runner design, porting, etc.) for that reason. But the exhaust valve does a lot of work when opening, and you need a softer lift off of the seat for the exhaust valve than you do for the intake valve. A lot of times even cams that show the same duration at 0.05" have different profiles for lower lifts.

 

Call TJ.