Severe Duty Valves Type: Intake

Name: Severe Duty Valves Type: Intake
Brand: MANLEY
SKU: 660-12346-8
Price: 311.48 USD
Availability: InStock

^$311⁴⁸

Ships on 09/25/2026

Lowest Price Guarantee

SB-Chevy and LS Series with 8mm Stem

Severe Duty Valves

Type: Intake
Length: +.100"
Head Diameter: 2.125"
Stem Diameter: .3133"
8/pkg

SMALL BLOCK CHEVROLET - AFR 180cc, 190cc, 195cc, 210cc, 220cc, 227cc,235cc, 245cc SERIES CYLINDER HEADS
Technical Notes:
Lightweight 8mm stems
LS (.060" single radius) style keeper grooves
Use Manley valve lock P/N 13098-16 (7°) or 13153-16 (10°) depending on your spring/retainer choice.
Manley stem sizes are .3136" (exh.) and .3133" (int.) respectively. AFR heads have guides sized to .3147" (nominal). Manley strongly recommends that allguides be checked and correctly sized (machine work required) for the Manley valve stem sizes listed to achieve the proper clearances.

Manley Stainless Steel Performance Valves are held to the highest standards. Swirl-polished heads, chromed stems and hardened tips provide the advantage you expect from America's premier valve manufacturer! Sold Individually or 8/pkg.

Budget Performance Replacement

For stock rebuild or mild performance applications
Superior to OE construction in every aspect

Street Flo

For street/strip applications
Fully-machined combustion faces and necked-down stems

Street Master
For bracket racer engines and street performance
Straight stems provide extra meat for outstanding durability

Race Flo
For mild drag or circle track engines and street performance
Necked-down stems for less weight and more flow

Race Master
For mild drag or circle track engines and street performance
Similar to Race Flo valves except with straight stems

Pro Flo
For drag, circle track, and hot street engines
Stainless steel undercut design for less weight and up to 40% more flow

Severe Duty
For applications with high spring pressures and high RPM
One-piece stainless steel design

Extreme Duty
For drag racing applications with 8000+ RPM
Offshore powerboat and Hi performance marine applications
Also, for engine builders using EV-8, high performance street, bracket racers, oval track and sportsman racers