Dyno numbers with 35" tires. Is this right?

[Dunin Duramax]

I am a new member and would like to ask the advice of many of you knowledgable people what the affect of larger tires has on the dyno, if any? Would the numbers be higher with stock tires or does it reduce by a certain percentage with each size gain in diameter? I ran the test with my 35x12.5x17 Procomp Xterrains. The numbers just seem low to me, but again, what do I know. The testing was done at PPE in Fullerton on their Mustang Dyno. They are posted below, let me know what you all think.

I recently had the trans upgraded by PPE with the Stage IV kit and purchased their Xcelerator programmer. I also have the Duramaximizer. The truck pulls much much stronger than when I was running the "Juice" w/Attitude and I love not having the speed limiter and having my speedo corrected for my larger tires. The truck runs very strong now and is much faster than before. Just want to know what you all think about the numbers. Thanks

STOCK
225.9 HP
388.4 TQ

DURAMAXIMIZER
255.6 HP
436.0 TQ

XCELERATOR
348.9 HP
685.7 TQ

XCELERATOR + DURAMAXIMIZER
362.5 HP
721.6 TQ

[WanaDmxsub]

34.5" tires (H's), everything else was stock.
3 runs, done with in a couple of minutes.
Dynojet (R&D Dyno service)
Avg. of the 3 was 240HP, 410 Tq

[Kennedy]

That's a little low for baseline, BUT you never know how your fuel system is functioning mechanically. I am assuming they had the optic tach hooked up?

As for the Juice/Attitude, the numbers posted pale in comparison. The stack is pretty close.

Also, watch out for false impressions. I had a guy tell me he SWORE that his Juice was faster than a particular box by his S-O-P dyno, yet the other proved 3 tenths quicker. Would have been nice in your case to dyno both setups...

[Dunin Duramax]

Yes, it would've been good to have both dyno'd. They told me too after they dyno'd it that the numbers were lower than what they got out of their truck which is 4WD with stock height tires. Yes, they had the optical tach running. The HP peeked out at 3200rpm just like their numbers on their truck. They thought it was because of the bigger tires because it pulls very strong when you drive it. It pulls a lot harder than the juice w/attitude did. Maybe I should throw the stock tires on and do it again.

[DATSBAD]

watch those mustang dynos . we have one in town and it is always off a good bit from a dynojet .