In this video I cover the important changes to the RH rotation small block Chevrolet marine engines from 1996 till the end of GM production in 2021. For years the RH rotation engines used timing gears instead of a chain. This allowed the usage of the same exact distributor gear in both LH and RH rotation engines. GM ceased production of RH engines in 1992. In 1996 with the introduction of the Votec engine two marine engine manufactures for sure converted LH engines to RH engines in their own facilites. Pleasurecraft (Crusader) and Marine Power were the two that I'm familiar with that converted LH engines to RH in house. They used a special roller cam, a timing chain unlike the older engines that utiized timing gears, and this setup required a different distributor gear. Even the 1987-1992 RH rotation small block engines used a hydraulic flat tappet cam and the LH or automotive rotation engines used a hydrualic roller cam. I also talk about the differene in the crankshaft reluctor for the RH rottion engine if you have an EFI engine. This is important and I'm sure down the road this will get mixed up.
The RH rotation hydraulic roller camshaft is Crusader part number RA050022 which originally fit 305 and 350 1996 till the end of production. 14097395 LH is the scribed number on the cam. This hydraulic roller grind is also used on the 383 truck and Ramjet 350 GM Performance Parts crate engines.
The 14097395 LH and RH cam specs are listed below:
The duration at lash point in degrees (intake/exhaust) is 288/308; duration at .050" tappet lift (intake/exhaust) is 196/206 and maximum lift with 1.5:1 rocker ratio (intake/exhaust) is 431/451. Valve lash is zero/zero and lobe centerline is 109 degrees.
The RH rotation cam is the above 14097395 GM grind on the LH core and uses the LH camshaft rotation distributor gear.
The RH crankshaft ruluctor is RA056001A and you utilize the "rounded" homeade slot.
5 сен 2024