On july 16th we have a diesel only dyno comp. here in town. I was wondering how much I can increase my hp #s by running with 265's instead of my 315's? There will be prizes so I would like to get all I can.

Mooseman

 

Your rear wheel HP will be the same with either size. Gear ratio,wheel size ect doesn't effect HP.
Topper

 

If they give you the standard 3 runs, just do a nascar style pit stop and swap the rear tires.

In theory, the HP shouldn't change, but it depends on how the Dyno figures the HP.
It might like the faster spin of the little tires, and liken that to more HP.


phox

 

by all means, let us know the results, then someone can stick the resuslts in the tech facts section.

 

The rolling resistance of the larger tires will cost you HP. NOthing huge, but could be up to 20-30hp if you have a high hp engine.

Just leave on your 315s and air them up (in the back) to the max rated pressure on the sidewall-- 80 for E rated, 65 for D rated.

This will minimize rolling resistance and keep hp loss at a minimum.

jmo

 

Depending on how many show up, I may take a set of 265's and try a few runs with each size.

Thanks Guys, Mooseman

 

Andy,

Where is this dyno at?

What prizes are to be had??

I have a set of EDM injectors setting in my toolbox that flow 55 lpm .

(100 HP extrude hone injectors flow 42 lpm!!)

 

The dyno is at Carls Accurate 1000 west 461 north in logan. They have not decided on the prizes for sure yet. They were talking something like 50.00 and your dyno fee back (nothing big) for first in your class. Not sure about second or third. As soon as they call me Ill let you know for sure. Come up and run or just BS. There is a local third gen. with twins putting down around 620. He needs some comp.

Andy