Just picked up 2 merc 900sc complete systems. Carbs are the merc 1050 dominators. One set has no power valves and 96 jets squared. And the other set has powervalves in the pri and sec and also has 96 jets. Anyone running There's motors. What is the standard jetting from merc how much boost do they usually run? Any info is greatly appreciated. Thanks

I can't verify but thought I would at least post this link. I would suspect no PV however someone will chime in but it does make sense to in this post that the forward carb has square 98's and the rear square 96's. Forward cylinders run a little leaner.

http://www.offshoreonly.com/forums/g...ng-900-sc.html

From http://www.mercruiserparts.com/bam/s.../31389/5158/60

- 1399-650896 --JET (.118) Primary
- 1399-650898 --JET (.125) Secondary
- 1396-9860 --POWER VALVE

Luckily, the last 2 #'s on the Merc jet part # are the Holley actual jet size #. + They list the hole size so we can double check, which I did.

So Primaries are #96's and Secondaries #98's.

Not sure on the PV, (maybe a 6.0 High flow) but we will have to figure that out some how.

Okay, the #9860 Power Valve is also used in the 525SC's. Years back I worked on a pair of Virgin 525SC Dom's and they had High Flow 6.5 Power Valves in them.

Hope this helps.

Thanks for the info. I'm still wondering why one set has the pv and the other set does not? Could it be that one that one of each style carbs should be on a setup?

If no one answers, a probable good contact would be Mark at Bam Marine. Goes by the name here of MBAM. Has a Mercruiser Parts dealership - www.mercruiserparts.com - and knows a lot about the Merc Racing Drives and engines. Also a sponsor here.