Diamond Coated Forged Piston/Pin/Ring Kits

APPLICATIONS:

• 1996-2008 Vehicles with L36/L67/L26/L32 3800 Series II/III engine

Diamond Forged Pistons are a big upgrade from stock cast aluminum pistons. Made with 2618 alloy, these are made specifically for the Series II/III 3800 engines. Built strong to handle high boost and compression, they have 0.250" undercrown thickness and premium 8629 alloy offset wrist pins.

Diamond Forged Piston/Pin/Ring Kits are custom dished with .905" x 2.500" chamfered 8629 wrist pins, new double pin oilers and complete ring sets (chrome steel top, cast compression and three-piece oil). The piston skirts are moly coated (for scuff resistance) and the tops are ceramic coated (thermal barrier). These pistons will also fit L36 engine, as long as L67/L32 connecting rods are used.

Stock L67 compression ratio is 8.5:1, and we offer two additional default compression ratios. We recommend using the 8.0:1 pistons for engines being converted over to more efficient superchargers or turbochargers, and the 9.5:1 pistons for engines that will retain their original M90 superchargers with high octane or water-meth injection. If you're running a better blower than the M90 you will benefit from running lower compression and working the new blower a little harder. If you're sticking with an M90 supercharger, you will often make more power by raising your compression ratio and decreasing the boost, putting the supercharger in a more efficient speed range.

We recommend boring your L67 over only .010" initially. This leaves additional room down the road if and when another overbore becomes necessary. At that point, you will still be safe with a .020" overbore.

Yes our pistons are expensive, but they come complete with wrist pins, pin-fitting and rings, and are the best quality you can buy. Diamond piston kits are built to order and they usually ship within 5-10 business days, so you don't have to wait months once you decide to upgrade to forged pistons.

Also keep in mind that our pistons feature two different coating processes. These two processes alone add approximately $250 to the kit price.

The common sizes available are:

• PKC-800 Diamond L67 Coated Piston/Pin/Ring Kit, 8.0:1, standard bore
• PKC-801 Diamond L67 Coated Piston/Pin/Ring Kit, 8.0:1, .010" oversized bore
• PKC-802 Diamond L67 Coated Piston/Rin/Ring Kit, 8.0:1, .020" oversized bore
• PKC-850 Diamond L67 Coated Piston/Rin/Ring Kit, 8.5:1, standard bore
• PKC-851 Diamond L67 Coated Piston/Pin/Ring Kit, 8.5:1, .010" oversized bore
• PKC-852 Diamond L67 Coated Piston/Rin/Ring Kit, 8.5:1, .020" oversized bore
• PKC-950 Diamond L67 Coated Piston/Rin/Ring Kit, 9.5:1, standard bore
• PKC-951 Diamond L67 Coated Piston/Pin/Ring Kit, 9.5:1, .010" oversized bore
• PKC-952 Diamond L67 Coated Piston/Pin/Ring Kit, 9.5:1, .020" oversized bore

Custom compressions and bore sizes are available, but will take a few weeks more lead time and incur a customization fee.

General Piston Specifications:
Compression height = 1.205"
Pin diameter = .905"
Ring widths = 1.5, 1.5, 3.0 mm.
Dish volumes = 3.5 - 4.0 cc (9.5:1), 13.3 cc (8.5:1) or 19.0 - 19.5 cc (8.0:1)

Piston Ring End-Gap Specifications:
Top ring: .020"
2nd ring: .022-024" unless gapless ring is used
Wiper ring: .015" minimum

When finishing cylinder bores you should use the following:
- Chrome moly rings need a rougher finish, such as a 220 grit stone.
- Plasma moly rings require a finish such as a 280 grit stone.

NOTES:

- As the pistons are ordered for your specific application, please be certain of your measurements. We do not want returns of this item and will apply hefty restocking fees (due to low demand and many size options).

- We recommend your Diamond Forged Piston/Pin/Ring Kit be installed by a competent professional. Much care is required and there is opportunity for things to go wrong.

- Diamond Forged Piston/Pin/Ring Kits are warranted for a period of ninety (90) days from the date of purchase against defects in materials and workmanship. The warranty provides for replacement parts only, and does not cover labor or any other costs. Purchaser and Installer assume all liability with regard to any and all damages in any way related to the purchase, installation and/or use of these pistons.

Average Customer Review:

There are currently no customer product reviews for the product.

Be the first to write an online review and share your thoughts with others.