Dyno results

[PJB]

Hi With my car heading to a Dyno here in NZ I’m curious as to how people interpret the results.

I understand that not all dynos are the same, but putting that aside they measure rear wheel results correct ?

Presuming that’s correct, what assumptions do you make to take it back to the advertised ..... factory figure for an auto (like mine)or a manual as I think the factory rating is at the engine, with minimal accessories etc.

To set my own expectations the headers and Weber seem to have perked it up but since the rebuild was in the late 80s and it’s done a good 160k km since then Im glad it runs well rather than being a powerhouse.

Thanks Julian.

[KOY 23]

Dyno figures are ideal for before and after tests to confirm that the shiny performance part has improved or decreased the power, it often happens!
You are absolutely correct in using the word assumptions as that’s all they are, depends on so many factors. The figures I’ve seen for manual boxes look about right, but autos vary wildly. I went to a reputable Stag garage where cars fitted with ZF boxes were giving up to 30% more power than standard.
Some Dynos will only give the measured power at the wheels and not calculate back to flywheel power. Not such an impressive figure but realistic.

[PJB]

Amy other input - how have other people translated the Dyno Rear wheel HP to "engine"?

[flying farmer]

Looking back at some of my rolling road figures it seems that adding about 27-28% to the wheel figures gives the flywheel figure, but that is on a manual box.

On an auto the low rpm torque figures are increased by the torque converter but at max rpm the converter should not be slipping much so the peak rpm power figure at the wheels should be about right.

The problems occur trying to calculate the power losses through a variable speed transmission on the run down hence the strange figures some auto boxes throw up.

Neil

[DJT]

Will there be a rolling road at Beaulieu? Having fitted a lot of new ignition parts recently, plus the Phoenix manifolds, recon Strombergs and with the ZF box, I would be interested to know what effect it all has had. I am very pleased with the overall results on the road as the get up and go is now better than I can ever remember. Particularly the mid-range kick-down acceleration from 40-70+