_Motions: HOMOLOGATION of the Volvo Penta GXI 5.7_ Current text: 9.1 Engine, Drive and Propeller homologation "Volvo Penta 5.7 GXi Engine model no: 3868947" "Any engine from the Volvo Penta 5.7 GXi Engine family 2001-2013 is allowed as long as they are identical to the older GXi engines (01-07) except from the new updated electrical system." Volvo Penta is still selling these GXi engines, but with updated electrical systems such as the EVC system. These engines should be allowed for anyone who wants to update their boat with a new fresh engine. But only as long as the new EVC engine are identical to the older GXi engines except from the updated EVC system. Current text: 9.2 General information "According to the class rules the ECM s may be interchanged between competing boats, thus chip tuning gives no advantage...more text..." "According to the class rules the ECM s may be interchanged between competing boats, thus chip tuning gives no advantage, if a boat runs the newer engine with the EVC electrical system and the new ECM the burden of evidence to prove that there has been no "chip tuning" lays on the crew running the boat, since the new and old boxes are not interchangeable...more text..." If 9.1 Engine is going to change, this will need to be added.
Current text: 9.3 Control System ECM: "Delco model 16220371 (1998) Volvo Penta P/N 3856511 Coded: 860371 KA00020058" Same as above but add: "EVC system and newer GXi ECM is allowed." If 9.1 Engine is going to change, this will need to be added.
Current text: 9.4 Cylinder head, valves, gas passages and camshaft Exhaust manifolds: Casting number: 3858759, both port and starboard Opening towards cylinder head: ~35 x ~37 mm Opening towards exhaust riser: ~ 40 x 73 mm Exhaust risers: Casting number: 3826213 Cooling water outlet to exhaust like at outer end (hose connection) of risers. Exhaust manifolds: Casting number: Any casting number associated with the Volvo Penta 5.7 GXi Opening towards cylinder head: ~35 x ~37 mm Opening towards exhaust riser: ~ 40 x 73 mm Exhaust risers: Casting number: Any casting number associated with the Volvo Penta 5.7 GXi or the custom made stainless steel risers only available from the V-24 builder Cooling water outlet to exhaust like at outer end (hose connection) of risers. Since Volvo released the 5.7 GXI there has been a couple of different casts when it comes to the exhaust manifolds and the risers. All the V-24 boats was also delivered with custom made risers from the V-24 manufacturer, we want that to be added just to be clear.
Current text: 9.4 Cylinder block, cylinder dimensions "Stroke: 88,4 +/- 0,15mm..." "Stroke: 88,4 +/- 0,15mm, it is allowed to polish or re-grind the crank in order to use over size bearings, stroke must stay the same." This is just to clarify that then crank can be repaired and that oversize bearings can be used. This is necessary to maintain these 10 year old engines. Current text: 9.4 Cylinder block, cylinder dimensions "Oversize pistons: ( First oversize allowed )" "Oversize pistons: First oversize allowed witch is: +0,50mm" Just to clarify what first oversize means
Current text: Cylinder block, cylinder dimensions "Deck height: Crankshaft center line / head surface 229,24 +/- 0,13mm..." "Deck height: Squish measurement must not be tighter then 1,15 /- 0,05mm" Measuring the block height in the boat during scrutineering is possible, but will most likely not give a good measurement reading, and the fact that the whole front end of the engine needs to be stripped most often results in no measurement of deck height being done. Using the squish measurement will help determinate two important things: *Deck height *Compression height of pistons One other benefit of using the squish measurement is also that anyone rebuilding their engine, is able to top-deck their block if needed and also, use what ever thickness of head gasket they need to ensure that they are not below the minimum squish.
Current text: 9.4 Cylinder head, valves, gas passages and camshaft Add: "Valve springs:" "Valve springs: It is allowed to shim the valve springs to the correct spring pressure or higher." It has come to our conclusion that a lot of engines fail when they get old due to the fact that valve springs will loose pressure over time and age. When that happens the engine gets in a state of valve float and that will cause lifter pump up and the result of that is the valve staying opened/out when the piston returns to TDC, collision is a fact. There is no performance gain in adding even more spring pressure if desired to ensure that this wont happen. It is actually the opposite if you add to much spring pressure you will lose performance since the valve mechanism will work under more pressure.