VTB(Erik)

I'm thinking not enough to matter.

DD

In terms of translating energy to driving power (as opposed ot handling), one of the biggest issues with larger unsprung weight is that a heavier wheel can have a higher moment of inertia. This is also, however, greatly affected by the shape of the wheel and the corresponding distribution of mass away from the hub.

This might be measurable when the dyno first starts and the rollers start moving.

Once the moment of inertia is overcome, and the wheel/tire mass is rolling, I would suspect that differences would be just as likely to be obscurred by minor imprecisions in the dyno measuring equipment, friction of the roller bearings, etc.

I don't know if the average shop dyno is precise enough to actually pick this up. We're talking about single digit percentage differences, at most.

DD

Pat

Yes, but not significantly. Any time the car is accellerating or decellerating it'll matter.

CTA4AVANT

Try to use a DynaPack AWD dyno. They connect directly to your hubs.

VTB(Erik)

That's about what I figured. It is 3rd gear pulls, so it won't matter much. Thanks.

VTB(Erik)

It's a dynojet, so rollers. I don't know if there is a dynapak in CO.

VTB(Erik)

Which dyno are the plots in your PP from?

Pat

Those are old charts with Italian (read: crappy) software. I've since dyno'd and done better. I'm still waiting to get to Parker to get them on disk so I can post them here.
I'd LOVE to see your dyno chart from the same dyno. That way I can tell if the extra money on the MTM stuff was really worth it.

VTB(Erik)

You got it.