This is all the info I can find on the engine, (don't know if I'm looking in all the right places) GM 5.7L SGI, which is on the port side aft of the engine. It has a Velvet drive 1:1. This inboard motor is in a 1991 GW Invader, Rivera 220 Sport Gold. I'm a newbie to the inboard world and have pick a really neat boat for skiing, wakeboard, kneeboarding, and tubing. As far as figuring out anything about this boat it sucks. If anybody can help it would be much APPERCIATED. Thanks in advance, Namder