Tire size vs gear down.

[Sheetmetalfab]

Here’s a Coronavirus quarantine thought.

if I increase tire size exactly the same amount percentage wise as portals gear the thing down.........

shouldn't the dct, speedometer and power be equal to stock?

 

[Admin]

 

[906UP]

Here’s a Coronavirus quarantine thought.

if I increase tire size exactly the same amount percentage wise as portals gear the thing down.........

shouldn't the dct, speedometer and power be equal to stock?

In theory yes but the gearbox (portals) require "X" amount of hp to run due to friction, inertia, etc.

 

[Sheetmetalfab]

In theory yes but the gearbox (portals) require "X" amount of hp to run due to friction, inertia, etc.

So shoot for a little overcompensation.

 

[PaulF]

In theory yes but the gearbox (portals) require "X" amount of hp to run due to friction, inertia, etc.

And heavier tires will also require some HP to rotate the extra mass.

So shoot for a little overcompensation.

I would but then you are back to the speed sensors being off a little. Not a big deal if you are off by less than 10%. If you are going to compensate more than that, you will need 2 VS sensor correctors for the DCT and another for the Speedo. And you will lose top speed unless you get a DynoJet PV3 and change those settings too.

 

[DDDonkey]

Here’s a Coronavirus quarantine thought.

if I increase tire size exactly the same amount percentage wise as portals gear the thing down.........

shouldn't the dct, speedometer and power be equal to stock?

Here you go, the stock tires on a pioneer is 27" bighorns and I put 35" system 3 xrc350 (34.6" true height) with 30% geared portals, so my top speed went from 66mph to 59 mph, I am now under geared. In order to have the DTC be correct I would have to run a 15% reduction and 33" or 30% reduction and 38" tall tires.


Check out the calculator on the SATV website.

Home Page - SuperATV

www.superatv.com

 

[SuperATV]

Dude... Game changer. Go high with the 15% if you're worried about your top speed. Go low with the 30% if you want bottom end power for mud or rock climbing. Either way...its a whole new level.

 

[SuperATV]

And just use your GPS for speed, and you don't have to worry about the speedo.

 

[aauman88]

I have 4” 30% portals and run 32” OutBack Max tires. I put the speedo corrector on by 12 o’clock labs and had to set it at +25 to get it correct because I was actually going 30mph when speedo said 40mph. And you only need corrector on rear diff for speedo, the one for DCT isn’t affected because portals are after it. Corrector was $80ish.
Loving my setup now. About to go up to 34 or 35” tires.

 

[aauman88]

Ah my apologies, I didn’t realize it was about a Talon. I will see if I can delete

 

[DDDonkey]

I have 4” 30% portals and run 32” OutBack Max tires. I put the speedo corrector on by 12 o’clock labs and had to set it at +25 to get it correct because I was actually going 30mph when speedo said 40mph. And you only need corrector on rear diff for speedo, the one for DCT isn’t affected because portals are after it. Corrector was $80ish.
Loving my setup now. About to go up to 34 or 35” tires.

View attachment 198941 View attachment 198942 View attachment 198943

@aauman88

I may need this speedo corrector your talking about, got a link?

Here is mine, just finished pithing the last week 4" portals and 35s. I am under geared just a little, I wish reverse what always geared this way.

Sorry for the derailing of the thread.

 

[aauman88]

Looks great. I want 35’s but I believe true 34 is as big as I can go on rear without scrubbing unless I pony up for the TTC arm setup with rear offset.
Here’s the corrector

SpeedoDRD

 

[DDDonkey]

Thank you!
The tires measure out at 34.6”

 

[Enigma]

Here you go, the stock tires on a pioneer is 27" bighorns and I put 35" system 3 xrc350 (34.6" true height) with 30% geared portals, so my top speed went from 66mph to 59 mph, I am now under geared. In order to have the DTC be correct I would have to run a 15% reduction and 33" or 30% reduction and 38" tall tires.


Check out the calculator on the SATV website.

Home Page - SuperATV

www.superatv.com

DDDonkey's explaination is spot on !!!!

 

[Enigma]

DDDonkey's explanation is spot on !!!!

 

[jamesh]

Top speed with portals seems like a bit of an oxymoron.