Tire/Wheel weight vs take-off power?

[TexasTruck]

I've been reading a lot around the physics behind rotational mass. Primarily as it relates to tire and wheel weight and the effect it has on getting a vehicle moving.

I'm running 305/55R20 General Grabbers ATx tires that weigh ~65 lbs. each. When I first mounted them on my truck, I noticed a difference right away with the effort it took to get the truck moving. Not terrible, but enough to notice my "normal" take-off/acceleration RPM is higher now.

I'm having trouble with the Generals (Roush tire/wheel take-offs) and have been looking at alternative tires. I've had good luck with Nittos and looked up the similar sized tire. Nitto offers a load range 116Q and 122Q in their 305/55/R20 Ridge Grappler. What caught my attention is the 116Q weighs 51 lbs. vs 63 respectively.

The common theme is for every 1 lbs. of rotational weight it's basically equivalent of reducing anywhere from 5-10 lbs. of static weight. With that in mind you can calculate that ~120-150 lbs. of static weight can mean a 15-20 BHP gain.

Will reducing the weight of each tire by 10+ lbs. make that much difference in getting the truck moving?

Reading material:
https://www.cjponyparts.com/resources/sprung-vs-unsprung-weight
https://www.w8ji.com/rotating_mass_acceleration.htm
https://www.tirebuyer.com/education/impact-of-wheel-weight
http://hpwizard.com/rotational-inertia.html
https://www.caranddriver.com/features/a15130598/upsized-wheels-tires/

TIA

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[Tall Tail]

Maybe a ~25% difference

Interested in what you have read. Any references?

 

[TexasTruck]

Updated post with reading materials...

 

[Heavishot]

Heavier tires definitely hurt my mpg but with my Livernois tune I don’t feel Any power loss. I image with stock tires it would be even more of a rocket ship.

 

[Codycat91]

Love to hear more feedback on this, as I’m currently shopping for wheels/tires. Wonder how much of a difference width has as well as wider tires have more ground contact and I would imagine more rolling resistance

 

[Dben]

I recently switched out my stock Pirelli tires for the 275/65r20 Recon Grapplers. Stock wheels. I can tell a difference, but it is minor.

Almost went with a ~65lb tire that was .5in larger. Glad I didn’t.

I don’t tow anything heavy.

 

[WhiteLightningnshitshadow]

yeah rotating mass is a huge problem. Think about riding a bike. I moved from 29x2.4 mud tires that were a pound heavier than the stock 2.2s and the pedalling effort was frankly ridiculous. I'm a bigger fan of the hard to come by skinnyish truck tires. If I could get something along the lines of a 255/75/18 to replace the 275/65/18s, Ill bet I'd lose some rotating mass and get some better mpg gains from the smaller wind profile.

I really wanted to entertain the idea of the rhino armory wheels, but they're way heavier than the stock XLT chrome 18s, which is a nonstarter.

 

[Cb Mw]

Nothing scientific, but when I added summer wheels (extra 15 lbs per corner), I noticed a decrease with acceleration.

With the stock wheels I'd use eco mode occasionally, not anymore. Regular mode is the new eco mode.

At high speeds on the highway the heavier setup does just as well, if not slightly better.

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