Calculating tire poke

I’m sure this has been discussed many times before but after searching this forum, using online calculators and talking to various people, I’m more confused than ever with calculating tire poke. Currently have a 17 TRD pro with 6” of total lift. Currently running 18x9 wheels with +1 offset, 35x12.5x18 tires. I have about 2 1/2” of tire poke currently. Hate the rims and tires. Would like to go to a 20x10 wheel with -18 offset with same size width in tires. Could somebody explain to me in detail how much more tire poke I’d end up with? Since you can run a 9”-12” wide rim, I don’t see how the rim width will affect the tire poke if you’re still on a 12 1/2” wide tire. Wouldn’t a -18 offset simply push the tire out 18 more millimeters than I currently have? One online place is telling me about an 1 1/4” more. Seriously confused and need help please.

 

this should be what you need-

 

Yup. It’s the one I used already and that’s where I came up with the extra 18mm of tire poke. I’ve found two others though that show two other results and I don’t know which one to believe.

 

Negative offset would push the tire out more giving you more "poke". Going from +1 to -18 is at least 19mm so about 3/4" more poke.

 

Kinda what I was thinking. Don’t see what the rim width has to do with it if the tire is the same width that you started with.

 

If you have not seen these, probably worth a look

https://www.tundras.com/threads/offset-and-backspace.255/

https://www.tundras.com/threads/wha...an-when-considering-aftermarket-wheels.88937/

 

A wider wheel will poke out more, because offset is based off the center of the wheel. Lets use easy numbers to illustrate. If you have a 10" wide and a 12" wide wheel at 0 offset on both, the 10" will have 5 inches on each side and the 12" will have 6 on each side. It will poke out an inch more with identical offset. This will have some effect on the tire, but if it's the same tire it should be similar poke at equal offsets.

 

Here you go. Explains exactly what you’re looking for.

https://www.tundras.com/posts/189124

 

Wheel width has zero effect on poke. Tire width will determine the poke.

 

Look at my build. I had 20x10 with -18 offset on 6" lift with 35.5x12.8x20 tires
https://www.tundras.com/threads/fotnots-ol-blue-build.65869/

 

You're adding about 19mm of negative offset, which is about 3/4 in. This is assuming wheel width and tire width are constant.

If the wheel and/or tire width is changing, increase/decrease the "poke" (I hate that term) by 1/2 the positive or negative value of the wheel/tire width change.

 

This isn't true - wheel width will definitely have an impact on "poke" - but not necessarily in instances where the tire width is far greater than the wheel width.

 

Yes, if your wheels look like this it will affect poke.

 

Even if it's less drastic than this it will effect "poke" - but this illustrates the point well.

 

@gizardlizard if you any questions, let me know. I did all the work on mine, so I know and (mostly) remember what had to be done to clear the tires

 

I'm guessing you used lots of lube....

 

Fotnot. I sent you a message. Hopefully you see it. Thank you so much.

 

Lube is for those that don't know how to get it going.... or when you're putting something somewhere that is maybe considered an unconditional.... well.... area

 

Thanks for the message and the pictures Fotnot. It helped BIGTIME

 

Pictures from Andy.... very dangerous.

 

Hey!

Eh....nevermind. fair point

 

Plenty more where those came from