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nick 08-19-2017 01:03 PM

Gearing
 
2 Attachment(s)
I have my 72 scout with the nissan sd33t ,t19 4sd, dana 300 with 44 frunt and rear running 33/12.50s. My qustion is what gearing are people running with this set up to go down the road at 65 but have the little extra power from the gears to pull a hill? I have 3.73 but and thinking 4.10 or 4.56 gears . Any input would be great. Also thinking of swaping in the nv4500 at some point. Thanks

Robert Kenney 08-19-2017 04:07 PM

Re: Gearing
 
4 Speed? You want to cruise at your highway speed at or just above your engines peak torque. Split the peak torque rpm and the peak hp rpm (3000 rpm) for better power. The closer you are to peak hp the more wear and tear you have but more surplus power.

Do these specs look right?

SPECIFICATIONS: SD-33T
DISPLACEMENT: 198 cid (3,246 cc)
BORE & STROKE: 3.273.94 in.
POWER: 101 hp @ 3,800 rpm
TORQUE: 175 lb-ft @ 2,200 rpm


5 speed: use 4th as a hill pulling gear.

Lots of rpm calculators out there. Punch in the variables and see where you end up.
Well I couldn't wait. :frown2:

@ 65 in 4th gear (1-1)

3.73=2470
4.10=2713
4.27=2826
4.56=3018
4.88=3230

dlang 01-21-2019 12:18 PM

Re: Gearing
 
I put together the page at http://lang.hm/scout/nph-performance6.cgi to try and figure out what gearing would make sense.

it lets you plug in different engine/trans/t-case/tires/gearing and compare the results across the board (at all speeds, not just at one)

plug in the specs for what you are currently driving and play with gear efficiency and wind resistance until it matches your current driving experience. Then add a second set and put in the changes that you are thinking about and it will help you figure out if it's an improvement or not.


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