EFI MPI question.

(rexlex01) · (rexlex01) **Join Date: Mar 2010** 10-07-2011, 12:54 PM

Does the 1993 - 1998 SN PCM 5.8 HO have the same EFI or MPI through all years?
What year motors had glitches more than others?
I am looking for the most reliable PCM EFI/MPI between 1993 and 1998

(tx_foilhead) · (tx_foilhead) **Join Date: Apr 2009** 10-07-2011, 4:16 PM

There were 2 motors, the Pro Boss and then the GT 40. The Pro Boss had throttle body injection that was tied to the ProTec ignition other than that it was the same as the carbed Pro Boss motors. The ProTec ignition will fail and there are no spare parts anymore. The fix is to remove everything and replace with a standard distributor and a carb, about $1100. You probably want the GT40 which became available around 95. The 3 motors are rated basically the same depending on which brochure you read. The ProTec is the only issue and it's not that big of a deal, mine has lasted over 900hrs. I'll be replacing it this winter because it seems I've lost a step of two out of the hole this year, but nothing bad enough to waste water time to do it. Having spent a lot of time with the Pro Boss and The GT40, I have no preference, when properly tuned I can't tell the difference.

(mikeski) · (mikeski) **Join Date: Aug 2003** 10-16-2011, 9:40 PM

1994 Ski Nautiques had the throttle body EFI, it is less desirable.

Late 1994- till they ran out of the Ford blocks were the GT-40 variety. Similar looking EFI setup to a Ford 5.0 Mustang with the throttle body on the side of the main common air runner. This is the desirable motor. Very torquey and bullet-proof.