Can a "tuner" fake a "before" dyno RWHP at less than it really is so when he puts on the "goodies" and retunes, it looks like you've really gained a lot where really you may not have gained much if any because he "faked" the original dyno results?

 

Sure.

 

Do you mean he de-tunes the engine for the "before" dyno, or he fakes the actual graph itself?

 

And who is this tuner

 

Ask for a log of the base pull...

 

Also ask for the atmosphere info to be printed on the graph. They can fake the temperature easy and not print it on the graph. You can swing the numbers a good 20-30hp. Seen it done. Also make sure it is SAE, not STD. Sometimes it makes no real difference, but it can. STD is usually higher.

 

This^^

Easiest way to fake it without the curve getting all screwed up

 

I am sure there are correction factors in the dyno that can be adjusted too. You can make a sensor tell you anything you want... most prefer the truth.

 

Is the tuner CNN? Would be fake for sure then

 

Holy ****! You win the internet today!

 

 

Tuner could take out a couple degrees of timing for the base pull, then add it back in after, especially if you aren't there for the dyno session.

 

CNN tuners deflate the tires before the base pull.

 

Stole it from Washington Post...

 

Then call the base tune "Trumps tune"

 

WHOA! A winning tune out of the box! Already optimum....

 

YUGE gains! YYUUGGEE!!

 

That fuked up!!!! The tuner just needs to do the job he/she was paid to do. I'm sure it takes more time/effort to fake it then to do it right. Some people!!!

 

100% agree! But "some people" will go the extra mile to fake something to impress the customer(aka sucker) by either deflating the base tune, or "fudging upward" the final tune. They DO get found out eventually, but too late for those beforehand.

 

Hardware wise, was anything done to justify a substantial gain in performance?

Just tuning an existing setup may make gains but may also be likely to knock if they pushed the timing too hard. Assuming it was running right in the first place.

But it also may very well be they found a simple issue if something was out of whack before they tuned it. Like maybe the MAF xfer function was off and mixture was off at wot or the fuel pressure was off setpoint, etc. They may have made the improvement honestly and the baseline may have been deflated through no fault of the tuner... Do you know what the AFR was at wot before going to tuner? Do you know what total timing your car likes?

In general always good to get multiple assessments of power. Like going to the strip for 1/4 mi to pair with dyno results before and after mods etc.

Also, I encourage everyone to familiarize themselves with as much of the tuning process as possible. Personally, I do everything myself. Longer learning curve at first but the results and understanding are worth it. That way you know whether someone is pulling a fast one on you.