Ok, its time to fix the motor that has a bad tick for almost 1.5 years now. Never failed to perform, but the noise from somewhere in the bottom end has started to finally make the knock sensors pull timing at light throttle just before shifts.

What I am looking at is this:

347ci Forged Assy with

2003 LS6 Block
2003 LS6 Crank (stock 3.622 stroke, Polished and Magnafluxed)
Eagle 6.125 Rods w/ARP 2000 bolts
Diamond Forged Pistons with 4130 Chromoly wrist pins(your choice of 3.905 dished, domed or flat tops)
Diamond Pro-Select File Fit Piston Rings
Federal Mogul Main Bearings
Federal Mogul Rod Bearings
Clevite 77 LS1 Cam Bearings
ARP Main Studs
Short will be fully machined, balanced, blueprinted and assembled.

curious what I pistons I need with stock 6.0L heads to make about 8.5:1 compression. Anything else I should ask about? upgrades, additional work to make it stronger? special coatings? better rods, etc.

will be going in my 2000 formula M6 with stage 1 Incon turbo's. currently has 42# injectors and with 10-11psi has run 11.05 @ 129.05 at 3860 raceweight.

Have ordered Motron 60#ers. Plan is to run 10psi on 93 octane all the time. Want to be able to turn the boost up to as much as 15-16#'s+, on race gas or a a meth/alchohol injection setup (not as straight fuel obviously).

Would like to get up to the limit of the stage 1 turbo's as possible on a safe tune, and have basically no worries. Thats like what? 675 rwhp?

Thanks for any suggestions you might have.

 

Looks good to me--

I'd add some ARP LS19 head studs so you can crank up the boost down the road if ya wanna. A lil $400 insurance.

Just a question: Why not go bigger cubes?

 

Thanks for the info. I already have standard arp studs in the car now.

hmm, what cam choice..... that'll be what to think about.

as for bigger cubes, that costs another ~1k which I dont want to spend. I would do the heads 1st before that. plus 550-600 rwhp on a mustang dyno for just driving around works good .

Then there's the "other" local TT pontiac that makes some nice power on stock cubes. I hear it traps 170+ lol who needs cubes to make power? I figure I can make <1/2 his level pretty safely with this setup. and have decent reliability.

 

Well, as a friend of mine says, for each atmosphere you add with FI, you double your cubes anyway

Wow a grand for bigger pistons and stroke - doh!

Yeah, 600 rwhp grocery-getters are pretty efficient

I'm shooting for that range myself.

 

Yes, unfortunately just a eagle crank goes ~900 bucks.

Good luck on your buildup.

 

Thats the bottom end I want for my GTO and a d1sc.

 

Sounds like you would need to order custom pistons from Diamond which take a little longer but it's no big deal.