TXoldskool

iTrader: (1)

I can't make the decision and pull the trigger on a new cam.


I have a '08 LY6 6.0L gen IV crate motor that I am converting from EFI w/VVT to carb'd w/o VVT. I want to go as hot as I cam with the cam, w/o going too big and killing the low and mid range. I finally have confirmation on the new GMPP LSX dual plane standard deck intake for L92/LS3 rectangular port style heads. Its ordered and will be here in a week or so. This brings me to the cam/springs/push rods. The LY6/L92 style heads have heavy intake valves so I plan on a spring upgrade and because of a more aggressive cam, push rods. I plan on keeping the OEM lifters, they are brand new.

The vehicle is a '68 GMC shortbed stepside and should weigh around 3800lbs (or less hopefully) when completed. The trans is a built 200-4r with 2500rpm stall converter and the rear has 3.73 gears with Eaton limited slip. The LY6 is stock except it won't be run by the OEM computer. I am using the MSD 6LS-2 to fire the OEM coil packs. I also have a Holley 750cfm Street HP carb and although I haven't chosen them, I plan on finding some 1 3/4" or possible 1 7/8" headers but will go with something that fits within the frame so it could be a mid-length set.
Comp recommended their 222/224 .566/.568 112+2, but I was thinking a little closer to .600 lift, and just a little more intake duration with a slightly larger intake/exhaust split....like 226/232 .588/.596 or something maybe. Wanting to keep close to 112 LSA. No cam expert... so I keep rehashing over and over in my mind w/o making a decision.

So...with a stock LY6 6.0L bottom end (minus VVT), the new LSX dual plane intake with 750HP for fuel, and MSD 6LS-2 and OEM coil packs for spark....what cam would you recommend for a truck that is not a DD...rather a "toy" that only would get driven to the track... or on a weekend cruise.


Not looking to rehash anything thats already done...just find the right cam. I want it hot...but not so hot it won't idle at or below 1000rpm, or cruise smoothly. Got any thoughts along that line?

BadAssChevy327

iTrader: (7)

forget daul planes. single plane it with a 850 and let some nitrous get the grunt out the hole lol.

sounds like a sweet, fun truck. i think ive heard people say to replace the lifters on VVT motors when camming it. but im not sure

budhayes3

iTrader: (19)

For what you're looking for (a cam in the 226+ intake duration range), you'll want more converter, I'd say 3000+. Have you considered any of the new Comp LSr cams? They seem to be geared more towards the L92 variety.

Here's one that's along the lines of what you mentioned:
227/235 .614/.621 113+4
http://www.compcams.com/Cam_Specs/Ca...csid=1402&sb=0

This one is a little less aggressive:
223/231 .610/.617 112+5
http://www.compcams.com/Cam_Specs/Ca...csid=1401&sb=0
It will be torquier than the 227 cam from both the shorter duration and the 5* of advance that's ground in to it...

and some valve springs specifically for the Comp LSr cams:
http://www.compperformancegroupstore...Category_Code=

I think that these grinds go along with your statement of

budhayes3

iTrader: (19)

I believe that it's the DOD lifters that should be replaced, but I too am not 100% sure lol

SweetS10V8

iTrader: (4)

BLASPHAMY!!!! New engines need keyboards & oxygen sensors not screwdrivers and sniffing the exhaust pipe!!!!.....

Comp has a new line of camshafts, some of which are specifically for for L92/LS3 port heads. They are called LSR cams, the L92 versions have wider splits and lift between .604"-.624". I'm running one myself and love it.

I'm running the 219/235 .607/.621 on my CNC L92/LS3 headed 6.0L, although the next larger part numbered cam is 227/243, they will make you a custom cam for no extra charge! Something in the middle of the two in the catalog is where I would go. I think the 223/239 .610/.624 113 would be good for you. If you don't like the Comps extra wide L92 specific split, just get the cathedral port version which has less split and is 223/231 .610/.617 112. (my brother has this one on his cathedral port and its great as well). I run the larger L92 split and it works great for me.

You also need to decide which cam core you want to run (3 bolt or single bolt) and get a matching timing chain set. becasue part numbers will change, or jsut order a custom cam and tell them how many bolts on the cam you want. (remember to match your timing chain too)

Then you need to get a standard LS3 timing chain cover, because when you remove the phaser and add the non phaser timing chain, the cam sensor will no longer be able to read beacsue the gap will be 2"+...

Just be sure to check PTV clearance!!! It has nothing to do with the lift either, its the huge 2.160" Intake valve and most likely no valve relief in the piston.

IF you have AFM (aka DOD) you have to completly remove it. Lifters, valley cover, tune, etc....

Here is a great article on some of the cams with carbs and fuel injection.....
http://www.hotrod.com/techarticles/e...est/index.html

TXoldskool

iTrader: (1)

My LSX L92/LS3 d/p intake is supposed to arrive tomorrow. I'll take pics of the ports and runners to post up...since I'm getting one of the 1st ones!

Tootall

iTrader: (79)

check out texas-speed.com under their LS3 cams . . .

1Bear

iTrader: (1)

Kurt, make sure and snap those pics when your new intake shows up. I know you’re glad the General finally got off their rear end and released it after only 2 years of advertising the damn thing. As far as a cam goes, I still like the MTI Racing Stage 2 which was designed around the LS3/L92 heads, 227/239 .614/.624 with an advertised powerband of 1800-6600rpm and is listed as providing a nice lope at idle. Granted a cam from any of our sponsors will work just as well, it's just something to look at to get you in the area of possibilities.

TXoldskool

iTrader: (1)

Yeah...I think the Comp tech is being too conservative with me...but of course it would also leave an upgrade path.

Anyway..............................here she is!