Tires too heavy?

agreed, but its virtually guaranteed a lighter tire will have less-rolling resistance than a heavier tire, barring wacky, outlier tread-patterns or cases.
Tread-pattern and weight are often contingent upon eachother in many offroad-truck applications, by virtue of the relationship between tread shape ,carcass, ply and "aggressive" action that sipe away mud/dirt/sand etc..

 

roughly ~$5 a tank.

the BIGGEST money you saved was silent. You GREATLY decreased the action of physics in its assault on your Hub/bearings/CV/drivetrain and motor strain.

unrelated note, I read somewhere once that ~1mpg of savings in the Semi-truck Over-the-Road world translates to roughly $10k monthly in overhead reduction.
That essentially every mile-per-gallon you gain in efficiency in a semi-truck results in a payback/return of $10k @ current diesel prices/avg.driver mileage

 

The first 60K miles with the E went well, no issues. The last 70K miles with the C have been trouble free.
If your hardcore then an E tire is good, everything else a good quality C or SL can probably handle it.

 

Or less profound. Because now we’re down to 230 hp. Unless the formula is meant to be applied to wheel hp because now we’re somewhere down below 200. Either way that formula is generally derived from the track racing folks and probably doesn’t apply quite so directly to a factory tuned truck driving around town. I don’t know about you guys, but I don’t drive around in the maximum power band of the engine all day. I’m no engineer but I believe turning big tires effectively is more of a function of torque. That’s why regearing is so common. Because gears are effectively a torque multiplier.

Either way it not black and white. Efficiency is the name of the game. And what degrades efficiency.....

Tire weight, wheel weight, tire size(too big or too small), inappropriate gear ratios, wind profile, rolling resistance(tread pattern), tire pressure and I’m sure the list could go on.

Moral of the story is do whatever you want with your trucks just don’t be too surprised when it doesn’t perform like stock.

OP- The few extra pounds on the tires you asked about will probably be mostly unnoticeable. Go for it.

 

Forgot a out the helium benefits for the low price of $99.99 for all 4 tires ( spare tire not included)

 

There will always be e rated bros trying to get more people to drink the cool aid.

 

Unsprung weight is a black and white value. it might be the only thing that elicits TRUE performance gains. more than most engine/exhaust/tuning mods could ever hope for. However, reducing unsprung weight is often EXPENSIVE vs other performance+ mods.

Im not sure if you were understanding the math right there... the OE tire theoretically weights 7lbs LESS than my original calculation accounted for. thats a MASSIVE reduction in unsprung weight. massive.

-Goodyearkevlar 265/70/16s @35lbs
-OEM TRD-OR wheel 16x8 offset +25mm @25.3lbs
Total: 60.3lbs per wheel/per corner
VS.
-Goodyearkevlar 265/70/16s @42lbs
-OEM TRD-OR wheel 16x8 offset +25mm @25.3lbs
Total: 67.3lbs per wheel/per corner

The delta is 7.3lbs of unsprung weight per wheel.
7.3(the difference in weight) x .5 (estimated 1/2hp loss per 1lb in drive train conversion efficency)=3.65hp (delta per wheel/percorner)
3.65(delta hp estimate)x4(all wheels)=~12HP recovery of drive-line power lost to mass increase in 42lb tire vs. 35lb tire)

Essentially, your motor would perform with the efficiency of 12hp additional power derived from increased efficiency in power-conversion-to-WHP thanks to mass reduction.

 

I am one of the few people that need and use D or E rated tires, I gold mine in the Nevada desert, we setup camp anywhere from 20 miles off pavement on dirt roads up to 65 miles off pavement, some areas, as the terrain changes on the dirt roads will have a rash of sharp rocks in the roadway, perhaps quartz rock or flint like rocks, those shards can make quick work of destroying your tires if P rated I have personally seen it several times, Speed is also a big factor in flats out there, 50 mph and you could impact sharp rocks thru the tread where if you traveled 20-30 mph no damage would generally occur with D or E tires with 3 ply sidewalls. The 6 ply TA/KO-2's are only 2 ply sidewall.

My 265/70/16 TA/KO-2's are D range, 8plies tread and the most important part, (3 ply sidewalls) which is where you get the most destruction in rocky areas, 2 ply sidewall tires and your guaranteed of at least one flat if not three per trip offroad where we travel. As long as you don't go up in tire diameter there is no noticable power loss or much if any mpg loss if you drive sanely. Only neg I have seen with the TA/KO-2's is once they are down to perhaps 5/32 of tread they do become quite noisy inside the cab. They are very quiet up to that point in time.

 

I understood. That’s why I said 230 hp.
60 lb stock vs 84 lb aftermarket = 48hp loss by your equation.

But 278 is stock crank hp. Does your formula subtract crank hp or whp? If it’s crank do you have to add 20% for the drivetrain loss? You’re leaving out some very key factors.

Also your 24x4=96lb hypothetical tire package is equivalent to 288 lbs of unsprung weight with your 3x formula. I don’t have 285s so I can’t say for sure but I bet I would notice the addition a lot more than having 288 lbs of wife and kids in the truck.

 

I get you now
So Everything is calculated off of "Crank Horsepower" because "wheel horse power" is an abstraction, rather than a "real" number.
-This is why manufacturers typically dont use it.
-A dyno measures "WHP" by a given vehicles ability to spin a drum. The computer is pre-programmed to interpret the drum RPMS as "WHP"
-this is why different dyno's produce different numbers for the same vehicle.
-thus WHP is an abstract number that isnt used for math here
-however, valid is your 20% drivetrain loss concern.

The type of "energy" this refers to is a physics term called 'potential energy'
-(which can exceed 278hp)(the motor has potential to perform better than the measured value the factory quotes)
-I will try to use "taxes" as an analogy to articulate a complex idea lol

what about the 20% drive-train loss?
-you simply multiply your final HP number after the equation I used by .2
Why?
Because your assuming that even though you may have just recovered or lost additional efficiency in turning POTENTIAL energy into a mass mover -- The result of eliminating or adding unsprung mass -- that this was a"pre-tax" gain, and your "20%drive-line loss estimate" is tax your drive train is paying (lol to the diff) no matter what:
-in both the case where efficiency increases, as well as where it decreases the diff is still going to consume a portion of this power when it does ITS translation of potential energy.
-the Wheels are the Only thing the motor is truly "driving". The motor connects to drive shafts, that connect to the diffs, that connect to the axls that connect to the wheels.
-this then essentially puts The mass of the wheels in direct relation to the motor ability to convert potential energy (which can exceed 278hp) to Crank HP
heres where "potential energy" finishes us off:
-because you lightened the bodies of mass directly connected to the motor itself (through an elaborate tax-system of shafts and diffs) the motor has accrued performance characteristics of a motor with additional(or less) HP.
Essentially it is converting potential energy at the rate a motor with the new performance stats would convert.


This is the most confoundingly difficult idea to articulate ever.
Race teams, engineers and Corporations pay people millions to figure this shit out.
and If I was able to articulate it any better than this LOL i would be one of those people. Its that hard.

hope any of this helped

 

That coolAid taste real good when I'm watching non-e rated bros trying to change a tire on Nevada razor sharp rocks.

I've seen Nevada trails destroy BFG's with no ply side walls.

If your playing in mud or running soft California pussie trails, non E tires are fine.

 

I guess im not as hardcore as you. You win . And you prob won't see me bc i dont have to stop for fuel every 200 miles.

 

Going to an E rated 66lb mud tire 265/75r16 mpg went down to 18mpg. Stock was 21 mpg.

 

No your not, so go back to your rock crawling thru fast food drive thru's

 

You got it! Do I know you in real life?

 

*youre

 

Ill chime in. I got stock size e rated bfgs ko2s. I did not know about load ratings, untill i went on TW. They ride fine, i have no complaints at all. If i could go back, i would get c load for sure.

The best part is i still get advertised mpgs or a bit better with e rated tires and my truck rips. I have never ever felt like it was underpowered at all, due to tires. Ill smoke 90% of cars on road no problem. My recent victim was 5.7 hemi, the guy was a bit surprised. I did hate myself a bit though when i did that hard shift from 1st to 2nd. It does feel nice when that rear end brakes loose for a second there.

 

VS.

 

paradoxically, lol math reaches a point where it looks more like "English" than it does anything else.
WHAT R ALL THOSE LETTERS

SOLIDS VS HOLLOWSSS