Outboard Engine GEAR RATIOS!

**tlwjkw** · 10-15-2016, 08:16 PM

happens a lot on here tha last few years............

**WillySteve** · 10-15-2016, 08:23 PM

Originally Posted by Mark75H

In the same way that a gear ratio would. Simply done by hydraulics instead of solid gears.

Wrong!!!
A TC is hooked between the engine and the input of the gear train and only multiplies torque to that input gear on a momentary basis.
Of course the final drive sees an increase because of this input increase.
Once the total stall speed of the TC is reached it no longer increases engine torque and is of no advantage other than a coupling!
There are no solid gears that can multiply torque to the input shaft which is coupled to the engine and seeing the engine torque!

**90 5.0** · 10-15-2016, 08:57 PM

I love threads like these, It separated the whey from the chaf and let's you know who knows what they are taking about and who doesn't.

Like eric said who cares , just test and see what combo accelerates hardest in your rig.

**NICE PAIR** · 10-15-2016, 09:36 PM

Originally Posted by 90 5.0

I love threads like these, It separated the whey from the chaf and let's you know who knows what they are taking about and who doesn't.

Like eric said who cares , just test and see what combo accelerates hardest in your rig.

Did we decide who knew what they were talking about

...................

**FORBESAUTO** · 10-15-2016, 10:35 PM

If lower speed gear does not multiply torque, explain why a 4:1 "torque multiplier" which is nothing but a gear reduction you hook a ratchet to allows a man to torque a bolt to 400 ft lbs and otherwise couldn't torque it to 200 ft lbs?

**dwilfong** · 10-16-2016, 08:04 AM

Originally Posted by NICE PAIR

Did we decide who knew what they were talking about

...................

I don't know I'm all wound up on tip speed I get from a dude in a single wide some where in Texas...........................LOL

**tlwjkw** · 10-16-2016, 08:21 AM

better be easy with what ya say say... you have no idea!... 'ole guys tend not ta really give a **** 'bout much..

**FMP** · 10-16-2016, 09:03 AM

Originally Posted by FORBESAUTO

If lower speed gear does not multiply torque, explain why a 4:1 "torque multiplier" which is nothing but a gear reduction you hook a ratchet to allows a man to torque a bolt to 400 ft lbs and otherwise couldn't torque it to 200 ft lbs?

How about we say, its the amount of work that can be done with the available engine torque that changes with the ratio based on load.

**NICE PAIR** · 10-16-2016, 09:11 AM

I have 2 motors, both have 1:62 gears
Look@ the pic and tell me what gear ratio I need on the port motor to pick up the speed I've lost.

Attachment 358074

**dwilfong** · 10-16-2016, 09:17 AM

more gear reduction dose make more toque at the prop shaft. But it reduces the prop shaft speed that it is delivered.
This dose not change the HP at the shaft.
So you can spin a bigger wheel but it will spin at a slower speed. With nothing else changed with the eng output.

**FMP** · 10-16-2016, 09:21 AM

You wont pick it all up, but a higher numerical may help. But then you know that . What is left in the starboard case?

**AZMIDLYF** · 10-16-2016, 09:35 AM

Originally Posted by NICE PAIR

I have 2 motors, both have 1:62 gears
Look@ the pic and tell me what gear ratio I need on the port motor to pick up the speed I've lost.

Attachment 358074

Click image for larger version.

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**NICE PAIR** · 10-16-2016, 09:52 AM

Originally Posted by FMP

You wont pick it all up, but a higher numerical may help. But then you know that . What is left in the starboard case?

everything except about 6" of propshaft ................... and a really nice humpback. ;-)

**NICE PAIR** · 10-16-2016, 09:54 AM

Originally Posted by AZMIDLYF

Attachment 358076

Good answer!

**Magcat 62** · 10-16-2016, 10:37 AM

Not exactly only when tc stator catches up with output shaft speed is lock-up final then horsepower takes over. it took over 100 mph for my nova to reach lock-up. i heard a quote once torque is doing more work slower and horsepower is doing less work faster. i think thats accurate and simple. physics. stall speed is peak torque in a race app.