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Vernier Timing Gears & Duplex Chain Kits

Vernier Timing Gears & Duplex Chain Kits

It is preferable to change from a single row chain (simplex) to a twin row chain (duplex) as the twin chain is less prone to stretching. The cam timing can also be optimised via an adjustable Vernier cam gear, or by using offset cam keys. Please see camshaft manufacturers data for correct timing figures.

Single row timing chains and gears were fitted as standard to MGB's manufactured after 1971 with 18V type engines. We offer several conversions to upgrade to the more reliable duplex chain.

Type 1. Full duplex and vernier conversion.
This kit contains all the components required including crank sprocket, vernier cam gear, uprated timing chain, tension and locktabs.

Type 2. Gear and chain kit
Contains crank sprocket, vernier cam gear and the uprated timing chain.

  Description Price
Kit, timing chain, duplex conversion Part Number: TMG10728 Application: Type 1
Gear, camshaft, vernier Part Number: TMG107281 Application: Type 2
Gear, cam, vernier Part Number: TMG10725 Application: Type 2
Timing Chain, 'duplex', high quality Part Number: 2H4905UR Application: Type 2
Lubricant, camshaft, kent, 250ml Part Number: KEN2 Notes: Use whenever cam followers and/or camshaft is fitted to ensure protection on start-up.
Disc, cam timing degree Part Number: TT2929