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Some RPM and MPH data comparing upsized tires on BD, BL and Squatch

GToddC5

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Thanks to no ManSquatch in 2021, my decision to go with 2 door manual trans. BD or BL, or auto trans. Squatch Package is a tough one. Like many here, I am interested in upsized tires and/or aftermarket wheels no matter which model I go with, as well as best bang for initial buck while allowing future mods. My gut says I want a manual, with 35" tires minimum - but damnit I like the 37s we were teased with. I don't want to re-gear in the future, but I don't want the rig to be a slug with big tires either. This will mainly be my daily, with some mild off-road thrown in from time to time.

I found a site with gear, rpm, mph, etc. calculators, and started playing with the numbers (God I hope I plugged everything in correctly): Linky

After pasting the options I created into Excel, what I found most interesting is that Squatched and running 37s @ 25 mph in first gear has similar RPM compared to stock BD and BL with manual, therefore should feel fine during acceleration? I did not apply a percentage to convertor slip to the Autos, because I wasn't sure what to put in there. Anything added raises the RPMs a bit more. I also included data for all combos running @ 2000 RPM in final gear, to compare MPH. I suppose I should put my flame suit on, because I'm really not sure how accurate this data is, and/or if I should be using different calculators, but I thought it was interesting:

Ford Bronco Some RPM and MPH data comparing upsized tires on BD, BL and Squatch 1607464243162


My struggle is:
* Do I get manual BD and slap on 285/75R17 to the stock steelies, and have slightly larger tires than BL while saving about 4K?
^ Cheapest option, but no 4.7 gears with that setup, so stuck at 34s without being too big a slug - possibly need a small lift.
* Do I get manual BL and go with aftermarket wheels and 35s or 37s?
^ Possibly need a small lift, and 37s may require gear swap $$.
* Do I get auto Squatched BD and be happy with the 35s for a while, then small lift and 37s down the road?
^ I'd really like a manual, but this option is moving to the top of my list. No gear swap needed, possibly need a small lift.
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Hey19

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One thing to consider is the calculator canā€™t tell you how it ā€œfeelsā€. I canā€™t help but think it will feel sluggish. Turning 35s or 37s is a big change
 

AzScorpion

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One thing to consider is the calculator canā€™t tell you how it ā€œfeelsā€. I canā€™t help but think it will feel sluggish. Turning 35s or 37s is a big change
I don't think it will with the 4.7 gears.
 

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Bronco_joe

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wheel size/material and type of tire will depend also. on my ram 2500 went from a 20inch 37 e load tire to a 17 inch 37 d load. forgot how much weight i saved per wheel but it was well noticeable in acceleration
 

AzScorpion

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And sport mode
Sport mode really works great. I have my Ranger tuned and it's like a rocket now. Even in drive I can chirp 2nd and 3rd. ?
 

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I ran the numbers a while ago for the MT on a BL. I think banging gears wonā€™t be an issue but passing at highway speeds may be a bit of a chore with larger tires. The double overdrive in the 7-speed is right on the line with where I believe the boost will be coming on based on the 2.3 stock ranger dynoā€™s. Even with 33ā€™s, I think a 7-6 downshift will be needed for quick passes.

This is what I put together for the 2.3/MT/4.7/33ā€™s. The color coding is based on where the torque and HP curves come up and drop off on the Ranger 2.3 dyno.

Gears across the top, RPM on the side and speed in the chart. Boost looked to come up around 2k RPM and fully on at 3k. I believe thatā€™s where on has to look when considering tire size upgrades. 7th gear might be about useless with 37ā€™s and a 2.3.

Ford Bronco Some RPM and MPH data comparing upsized tires on BD, BL and Squatch 1C8B2AD9-574F-4D78-A821-48BF1A6C7F2B
 

Gr8Hortoni

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The only problem with 285/75r17 is youā€™re gonna need a slight leveling kit to clear them (this is exactly where Iā€™m going with my stock BD). 70ā€™s will clear, 75 needs a little help. All the tire talk last week helped me immensely. The 4.46ā€™s should be plenty for that size as well.

Stock manual BD on 75ā€™s is my vote

Edit: rubiconā€™s have been running 33 to 35 inch tires for ages on 4.10ā€™s competently, I cannot for the life of me understand why everyone thinks they need to regear 4.46ā€™s for anything bigger than a 33ā€.
 

Hey19

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I don't think it will with the 4.7 gears.
They will definitely help. I went from stock 32ā€ to 35ā€MTs in my F150. No gearing change. Completely different animal. The 5.0 coyote will still accelerate smartly with more throttle input. Need more brakes to slow it down. Dropped 2 mpg.

It will feel different. You canā€™t escape physics but it should be manageable.
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