Mercury Through The Years...

**FUJIMO** · 08-04-2017, 02:35 PM

**bernie** · 08-04-2017, 08:21 PM

Originally Posted by FUJIMO

I think I rigged that one and we did a BHB on it and then some photos. ActionCraft wanted 50 MPH - I was stuck at like 49.8 radar. Took it in the shop - drilled out the carb jets, viola! 51 and change!

**powerabout** · 08-05-2017, 07:47 PM

it went faster when it was richer???

**Capt.Insane-o** · 08-05-2017, 09:57 PM

If you drill out opti carb jets they do.

**bernie** · 08-06-2017, 08:29 AM

Originally Posted by Capt.Insane-o

If you drill out opti carb jets they do.

OK that wasn't the boat - didn't notice the decals - just the back one. It was a 135 carbie I did that to. Memory is going fast - hell, it was only 15 years ago.

**Capt.Insane-o** · 08-06-2017, 08:39 AM

**FUJIMO** · 08-10-2017, 12:20 PM

...Mercury Racing - Go Fast, Go Boldly! - https://youtu.be/US7g2DFuWi8

**FUJIMO** · 08-10-2017, 12:38 PM

**bernie** · 08-10-2017, 01:02 PM

Or this:

Click image for larger version.

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Or this:

Click image for larger version.

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**2us70** · 08-10-2017, 03:42 PM

What lower unit is on the 700X? It would seem that a single pinion lower unit would be sufficient for a 49in motor.

**bernie** · 08-10-2017, 04:31 PM

Originally Posted by 2us70

What lower unit is on the 700X? It would seem that a single pinion lower unit would be sufficient for a 49in motor.

From what I have heard it was a 16/23 ratio with one driveshaft and pinion. Don't know that for a fact, but makes sense.

**2us70** · 08-10-2017, 06:14 PM

I wonder if that ratio would allow it to use props for the larger speedmaster motors? Mercury practice was to make props for the larger motors usable on smaller motors running the same family of lower units. The 50s could run the 650 props and the 850s the 1500 props.

**Mark75H** · 08-10-2017, 09:10 PM

Originally Posted by bernie

From what I have heard it was a 16/23 ratio with one driveshaft and pinion. Don't know that for a fact, but makes sense.

The Hi Perf catalog says they had 13/16 ratio. Rumor is that std motors came with single pinion, but motors that dyno'ed 'extra' came with dual pinion. I think its more likely that Merc set some up for marathons vs sprint ... could be that the marathon motors were indeed 'extra' hp motors sent to specific racers

**powerabout** · 08-10-2017, 10:22 PM

Originally Posted by Mark75H

The Hi Perf catalog says they had 13/16 ratio. Rumor is that std motors came with single pinion, but motors that dyno'ed 'extra' came with dual pinion. I think its more likely that Merc set some up for marathons vs sprint ... could be that the marathon motors were indeed 'extra' hp motors sent to specific racers

Omc Started to race mod 50 with one pinion late in the game

**bernie** · 08-11-2017, 09:17 AM

Originally Posted by Mark75H

The Hi Perf catalog says they had 13/16 ratio. Rumor is that std motors came with single pinion, but motors that dyno'ed 'extra' came with dual pinion. I think its more likely that Merc set some up for marathons vs sprint ... could be that the marathon motors were indeed 'extra' hp motors sent to specific racers

Yeah, 13/16 ratio - senior moment on that gear ratio. Saw one of the Merc 49 CID looper powerheads a month ago in Canada - now I have seen two of them - I think there were only 5.