In the process of purchasing a 402 stroker from the classifieds and wanted some opinions on head and cam combos for turbocharging.

Specs on short block:
03 6.0 iron block
Mahle Forged 402 cid LS1 Dished Piston Set: 4.005" Bore, 4.00" Stroke -12cc
Scat 4.0 forged crank and 6.125 H-beam rods

I am looking for the best option for the dollar but also keeping in mind money isnt an option (if that makes sense). Not sure about the turbo setup yet but I am looking to put at least 700-800 hp on the ground. Its for a 05 GTO and this car will be driven street and strip (just a toy not a daily driver).

 

Here's a list of my engine build. What i can tell you from my build which is getting close to done is that my motor and rear mount turbo are going to get me to my goal of 620-650 rwhp with no problems.

I've already dyno'd 406 rwhp and 512 lb/ft torque with my setup at 4,000 rpms (couldn't go higher due to an unforseen issue), with a 5# wastegate spring in and a relatively stock exhaust setup. When my car spins to 6,500rpms it'll likely make 520-550 rwhp and close to 575-600 lb/ft torque with only 5lbs boost.

LS2 402ci Forged Engine Specs:
Aluminum LS2 402
Wiseco K396X05 Pistons with Full Floating Pins, GFX Nitrate Steel Top Rings, Napier Ductile Iron 2nd (Side clearance 0.0035”, Gap top 0.022”, 2nd 0.024”)
NGK TR6 Spark Plugs and MSD 10.4mm spark plug wires
K1 Forged 4340 Steel 4.0” Stroke Crank, K1 Forged 4340 Steel 6.125” H-Beam Rods
Clevite H-Main Bearing Clearanced to 0.0024”, Rod Bearings Clearanced to 0.0024”, GM Cam Bearings
Cam Motion Turbo Cam 228/222 (Duration 576/576) Lobe Separation 0.115
HD Single IWIS Timing Chain, GM Chain Tensioner
ARP Main Stud Kit, ARP 12pt Thread Stud Kit
AFR 225cc Cylinder Heads with Patriot Extreme Dual Valve Springs (spark plug 14mm x ¾”)
LS2 Conversion Kit (Valley Cover/Gasket, Front Cover/Gasket, Crank Seal, Rear Cover/Gasket, Racetronix Knock/Cam Harness, LS2 Lifter Trays, LS2 Cam Timing Gear)
Fel Pro Oil Pan Gasket, GM MLS 7.0L Head Gaskets
GM LS7 Lifters, Comp Moly Push Rods 7.350”, Yella Terra Ultra Lite Roller Rockers
Keyway’d Crank and Balancer (SLP Underdrive Pulley)
Rear Coolant Crossover for Cylinder Heads
Cylinder Bore Size: 4.005
Piston Stroke Length: 4.00
Head Gasket Bore Diameter: 4.160
Compressed Head Gasket Thickness: 0.051
Combustion Chamber Volume (CC’s): 67
Piston Dome Volume (CC’s): -32
Piston Deck Clearance: -0.002
Compression Ratio: 8.5 – 1
Total Displacement Volume: 110cc

Ryan

 

For 700-800hp all you need is a set of ported 317s, a good gasket, and some arp studs. I went with the TFS 220cc as cast heads with upgraded valves since i plan on running 900-1,000rwhp, which are also a budget option. If money wasnt an option for me I would have went with a set of TFS 235s or a set of MAST heads.

Any of the sponsors can spec you a good turbo cam. Most of them have off the shelf cams that will work with most combos, but you'd be better off having one matched for what you want out of the combo and what heads/intake/turbo youll be using.