Bulletin No. 1.62-15 Group No. 1.62 March 10, 2008 Page 1 of 2

350 SERIES PISTONS AND RING SETS

Effective March 15^th, 2008, we have upgraded our cylinder kits for turbocharged 350 Series Powertech applications. These cylinder kits are suitable to all 4.5 and 6.8 Powertech engines, but should not be interchanged with previous part numbers within the same engine.

The differences between these cylinder kits and the earlier versions are the piston and piston rings. The upgraded versions include torsional keystone top rings for improved reliability and engine life. These ring sets may not be used with the earlier style pistons. Great care should be taken not to intermix current pistons and ring sets with earlier versions of these components.

Attached is a drawing showing current and former ring set components. If you have additional questions, please contact Reliance Technical Support.

Bulletin No. 1.62-15 Group No. 1.62 March 10, 2008 Page 2 of 2

4.5 and 6.8 Powertech Ring Sets

Former

Ring Set

Former

Ring Set

Current

Ring Set

NRE66271

NRE66820

NRE507852

Top Ring Profile

Full Keystone

Torsional Keystone

Dimensions

(Height x Width)

2.35 x 3.75mm

0.092 x 0.147”

3.00 x 4.35mm

0.118 x 0.171”

3.00 x 4.35mm

0.118 x 0.171”

Middle Ring Profile

Reverse Torsional

Dimensions

(Height x Width)

2.35 x 4.70mm

0.092 x 0.185”

2.35 x 4.70mm

0.092 x 0.185”

2.35 x 4.70mm

0.092 x 0.185”

Bottom Ring Profile

Coil Spring Loaded Beveled Oil Control Ring

Dimensions

(Height x Width)

3.45 x 2.80mm

0.135 x 0.110”

3.45 x 3.15mm

0.135 x 0.124

3.45 x 2.80mm

0.135 x 0.110”

Used on Pistons Marked

NRE505100, NRE505101

NRE505102

NRE509540, NRE515372

Used in Cylinder Kits

NRE505110, NRE505111

NRE505112

NRE507850, NRE507920

Please note that each set differs only slightly. Caution should be exercised, as none of these are interchangeable and must be used in combination with the pistons and cylinder kits as shown only.