That_Z28_Camaro

I should have asked this question before I bought the engine but I wanted to get some opinions here...this is what i'm working with


-Texas Speed & Performance Custom Built Forged 402 CID
-Wiseco Forged Piston Set: 4.005' Bore, 4.000' Stroke, 6.125' Rod Length, -3cc Flat-Top, 1.110' CH, Wrist Pins & Steel Top/Napier 2nd Ring Set Included NoPRings
-PRC LS3 260CC CNC Cylinder Head
-Camshaft 242/250 .624/.624 112 LSA


Was hoping for 520whp though a 9" so I was just wanted to hear what you guys have to say here. Really wishing I had a higher compression ratio right about now...

427zm

iTrader: (9)

With your setup, all you need for higher compression all you need to do is mill the heads. Tighten up the chambers, check PTV and let it eat.

carbuff

iTrader: (8)

What is the combustion chamber size? What is the deck height? Did TSP assemble the entire motor and tell you it's at 10.5:1?

That_Z28_Camaro

Called TSP and the chambers are 68cc. Furthermore he told me the compression would be at 11.2

HCI2000SS

iTrader: (2)

11.2 with the 68cc?

speedtigger

iTrader: (16)

Do you know the deck height? If they did not mill the block, the pistons will be down the hole .005" with that compression height.

Piston .005" down the hole = 10.95:1 compression (factory 9.240" deck height)
Piston .000 deck height = 11.08:1 compression (block deck milled .005" to 9.235")
Piston .005 out of the deck = 11.21:1 compression (block deck milled .010" to 9.230")

That_Z28_Camaro

There was no milling involved that I know of. I forget if it was 11.1 or 11.2 to be exact but I think he said 11.2. I'll just run this the way it is right now and see how it performs. Appreciate the help guys

Sales2@Texas-speed

iTrader: (5)

I'd have to look at your specific build but pretty much every block that leaves gets decked to insure straightness. The 1.110 compression height is for a 9.235 deck height and I'm pretty positive the block was decked to 9.235. I've found that most motors are .003-.005 out of the hole.

SS69LS1

iTrader: (108)

for comparison I have an LS2 based 402 approx 11.5:1 TSP CNC cathedral 243s and comp 235/242 620/593 111+3. Thru a 6 speed, moser 12 bolt w 4.10s it made 537.
Scott

That_Z28_Camaro

Thanks for the clarification and the build sheet as well


Awesome! That's reassuring so I shouldn't be that far off