Opinions.....

[oldeskewltoy]

Can a scale change make a difference?

Below is my 30 month old dyno run... decent for a largeport 4AGE with street cams





Well... I always explain away(was disappointed) the scale being set for 500 hp. The chart doesn't look impressive even if the numbers are adequate... (us Americans and size... YEAH get over it... )

back to my point.... earlier today I did a bit of scale "adjustment"....



Is this legitimate? Does stretching the scale.... change what it shows??

and if it is legit, then something exposed itself to me when I did stretch it........ I seem to have a flat spot between 6100-6300 rpm. both lines appear to have blips in the same place..... and then resume their previous expected paths....

[Draven]

absolutely no problem stretching the scale... it's still showing the same info.

that's gotta be the smallest flatspot in history

[Hiro]

It's a linear scale, so stretching does nothing bad....

As for the flatspot (if you could call it that), I wouldn't worry at all. Every engine has it's own little ups and downs, such things could be as simple as a small bit of resonance in the intake, or any other number of small things, all of which aren't going to affect things in the long run. An engine that old, with big cams, is never going to have a smooth power curve.

As an example, here's my AE82 bigport's latest dyno run. Note the number of "flatspots" it has, and the AFRs all over the place, yet it still produces relatively healthy numbers (and that is essentially stock)