Forum Discussion

thames's avatar
thames
Explorer
Aug 25, 2015

Engine Identification help pls

Hi guys,

Trying to identify the engines I saw on two 1998 MH.... a Thor/4winds Infinity and a Triple E Commander. I know they are both Chevy 7.4L but wondering about the Vortec thing. I thought all Vortec had the VORTEC logo on some sort of black box on the top but it was not the case for both of them. Unless that box is at a different location in the compartment (compared to a pickup truck). Thanks !
  • Looks like the 7.4 was made in two versions. The L29 version (1996-2000) was made for light duty trucks and the L21 version (1998-2001) was made for commercial applications including the P12 HD and W20 motorhome chassis. It's possible GM didn't use the Vortec logo in the commercial applications of the engine.
  • I'll try to post pictures of the engine compartment (sometimes called "dog house" right?) later tonight.
  • I had a '96 Pace Arrow that had the Vortec on the valve lifter covers. That was the first year for the Vortec as I was told.
  • I've always understood that all Chevy engines built since 1995 had the Vortec heads. Not true?

    Ron
  • The 1996 model year, P series motorhome engine was up dated from throttle body to port injection and labeled Vortec. HP was increased by 45.

    Richard