it's a MEFI 1 with the proper calibration you can set it up for a GI orGSI. They are available and so is the calibration. Your other option as noted is the 2600 or more MEFI 4 conversion.

Ouch, that's a steep conversion. Not sure what I’m going to do with this boat yet but 48GPS is painful. Originally thought of Procharger but Procharger doesn’t offer a kit for the 7.4 VP. Then I was considering a 509 with the VP Gi intake & ignition but the conversion doesn’t seem cost effective. Guess I’ll go back to carbed 509 or just live with the VP Gi?

I've added 496 manifolds & K&N intake filter to this set up & it seems to have lost power? After these mods the boat was in the low 40's GPS. Last weekend I put the stock intake screen back on, 1/4 of fuel, 4 adults the speed is back to 47.5GPS? Does the MEFI need to be reprogramed to take advantage of the better free flowing intake & exhaust manifolds?

if in fact your Cobalt engine is a 1999 and Volvo lists by model number to determine year so with that said if that model number has a WT in it then its a 1999 year model so it should be a a MEFI 3 ecm not a MEFI 1 ecm.

Volvo ECM follows as such MEFI 1 basically up to mid 1998 in which is BY models .

Volvo had no MEFI 2 as they did not even offer it, they went right into MEFI 3 for very late 1998 or very early 1999

Volvo very late 2001 or early 2002 went to MEFI 4
Volvo late 2004 or early 2005 went to E controls no more MEFI controllers for them.

Volvo has used E controls ECM's for the past 10 to 11 years

FYI.

The ECM # is 74LOPFI/99BZ02 & the engine # is the 7.4Gi PWTR. I really don't understand why with better flowing exhaust/ intake & a lake that's 1000' lower in elevation the boat is slower than stock? I think I should be 1 or 2 miles GPS better? It was only two people in the boat when it did 48.5gps but the lake was @ 6000' elevation not 4900' w/ four of us & better exhaust.

Your being limited by your cam, after market exhaust will ad character to the exhaust note and a new intake may improve induction but not matter what you try the cam is holding you back.....maybe the timing curve could be adjusted a bit but not enough to make any real world difference Is this a TBI engine or MPI if its mpi marine intakes are setup differently than automotive they use larger injectors and are sought after by the car community for performance. Thats for the 5.7 as to a 7.4 who know's but why build for a 5.7 and not a 7.4??? lol who knows

http://www.pacificp.com/forum/viewtopic.php?t=317