New addition to the 408 for the turbo, Wiseco -15cc pistons to bring down the compression and get the 408 back in the truck. These ought to help a lot. Next, I have to decide which heads I want to run, stock LQ4 with dual Patriot Platinum Extreme springs or the larger valved Patriot ported heads but with 64cc domes which will raise compression.
Patriot Performance Heads
2.08 intakes / 1.60 exhaust
64cc
air flow numbers...
lift intake exhuast
.10 78.9 63.2
.20 150.5 123.5
.30 212.9 165.9
.40 261.0 195.1
.50 296.3 216.2
.55 307.4 220.0
.60 311.3 222.2
Dual springs w/titanium retainers good to .650 lift
Wiseco Pistons - Chevy
LS-1/LS-2/6.0
Included: Pistons, Rings, Pins & Spirolox, Skirt Coatings
NOTES - Please Read:
- LS-1 block has 9.240 deck, 6.0 truck block has 9.230, LSX block is
approximately 9.255. Pick rod length accordingly
- 4.070 bores or smaller take all but LS7 valve sizes.
- All bores 4.100 take any valve size including LS7
As the leader in LS-1 forged pistons, Wiseco pulled out all the stops when designing this series. They are designed to accommodate the reluctor ring on stroker cranks without having to notch the pin bosses. Offset pins like o.e. and skirt shapes specifically designed for street applications make these the best available. They have been tested successfully in the highest horsepower applications.
All Pistons Feature:
- NEW Coated skirts for LS Series Pistons. Much higher adherence factor then other moly coatings.
- 2618 Alloy: Will not shatter like hypereutectic, or cast pistons.
- Strutted skirt design is the strongest and specially designed to run at as little as .004" clearance, with excellent skirt wear and minimal noise or rock.
- Radius valve pockets for detonation resistance and increased flow around valves.
- Anti Detonation Grooves with the added benefit of keeping the top ring groove free of carbon
- 3mm oil rings for better oil control and reduced friction for more horsepower
- Pressure groove for enhanced ring seal
- Features Chrome Moly pins and spiralox, tool steel pins optional
- Race Ready domes don't require deburring by the engine builder
- Multi-fit valve pckets for interchangeability of cylinder heads
445X3 pistons
4.030" bore
suggested clearance .0035", measured 1.300" from bottom of oil groove
4.000" stroke
6.125" rod
1.110" compression height
-15cc dish
450gm average weight
65cc 10.2cr
67cc 10.0cr
68cc 9.9cr
70cc 9.7cr
ring set 4032GFX
piston pin S643 .927 x 2.250
Retainer clip CS24
piston rings..
oil ring support GLS25
top ring groove width .0490
2nd ring groove width .0490
ring groove width .1498
left side piston...6445LX3
right side piston...6445RX3
file fit piston ring set....
oil ring end gap .010"
top ring steel nitrided, positive twist2nd ring ductile iron Napier style
minimum gap per inch of bore=========== top ring===== 2nd ring
high perf street/strip================== .0045 ======.0050
street moderate turbo/nitrous=========== .0050 =======.0055
late model stock===================== .0050 =======.0053
circle track/drag race================= .0055========.0057
nitrous race only===================== .0070=======.0073
blown race only====================== .0060=======.0063
2nd ring gap should be larger than the top ring to reduce ring flutter.... Jon was right.