The Enginetech ST181255 is a 4-pack of intake-side valve seats engineered as a stock replacement for 1985-2005 Buick, Chevrolet, GMC, Isuzu and more engine applications.
Important Notes
- Sold as a 4-pack.
- Application side: Intake valve position - confirm you are replacing the correct side.
- Seat angle: 45deg - confirm head casting matches specified angle before installation.
- Hi-chromium cast construction: standard durable alloy for gasoline applications and general valve-job rebuilds.
Specifications
| Brand | Enginetech |
| Part Number | ST181255 |
| Product Type | Valve Seats |
| Quantity per Pack | 4 |
| Inner Diameter | 1.500/1.555T" |
| Outer Diameter | 1.8195" |
| Thickness | .2780" |
| Seat Angle | 45deg |
| Material | Hi-Chrome Cast |
| Application Side | Intake |
| Country of Origin | United States |
| OEM / Aftermarket Cross References | Manley:39710, Elgin:A1812131278, Clevite:27181255, FEL-PRO:245181255, Perfect Circle:2187828, Dynagear:39710, SB International:SB1812-55, Dura-Bond Bearing:31285, Dura-Bond Bearing:50026, Infiniti:11098V5210, Infiniti:11098V5211, TRW:IS527, MAHLE:27181255, Qualcast:20-1812-55, Nissan:11098V5210, Nissan:11098V5211 |
Vehicle Fitment
- Years: 1985-2005
- Makes: Buick, Chevrolet, GMC, Isuzu, Mercury, Nissan, Oldsmobile, Pontiac
- Models: 200SX, Beretta, Cavalier, Century, Corsica, Cutlass Ciera, D21, Firenza, Grand Prix, Hombre, LLV, Lumina, Malibu, Maxima, Pathfinder, Pickup, Quest, S10, Skyhawk, Sonoma, Sunfire, Villager
Valve seats are precision-machined rings press-fit or cast into the cylinder head to form the sealing surface between the valve face and the combustion chamber. Over time, exhaust seats erode from hot combustion gases, suffer impact damage from valve float, or lose geometry from repeated valve-grinding operations - any of which leads to lost compression, burnt valves, and rough idle. Installing new valve seats during a head rebuild restores correct seat angle, sealing pressure, and thermal contact between the valve and the cylinder head.
WARNING: This product can expose you to chemicals known to the State of California to cause cancer and/or reproductive harm, including lead and nickel.
