Direct charge

[ironlake2]

How did this differ from the deflector motor; was it
more like loop charging.

[Mark75H]

Merc's advertising made it seem like a big difference, but its still a deflector.

It differed from earlier deflectors by having less piston surface area and good jetting of the intake flow. Regular deflectors have twice the piston area of a loop charged motor and rely on bulk flow into the cylinder rather than directed flow.

It increased the power less than 10% from 125 to 135 on the 6 and 80 to 85 on the 4 ... not very impressive

[mk30h]

Sam, I didn't think that the 1969 Merc 800 was a straight cross flow, wasn't it DC from the begining? The 69 650 was 62 cu (i think) and the 800 was 66,
I was suprised that 4 cu could result in 15 hp difference between the 2 engines. Always assumed it was because of DC, but could really never understand if it was really superior to a straight crossflow or more of a marketing ploy.

[25ss]

One thing i like about the early ones is with all the surface area you can run alot more timing.
Too much on the newer ones takes out the center of the deflector.
Usually starts on #3 cylinder.
Dale

[Mark75H]

One thing i like about the early ones is with all the surface area you can run alot more timing.
Too much on the newer ones takes out the center of the deflector.
Usually starts on #3 cylinder.
Dale

I think that is because the older ones had much lower compression and the newer ones have a lot more ... putting you closer to the edge with timing