08 and up 103 build with your hands tied (Stock pistons, OEM dbw TB with mods)

[Matt C]

DynoJet readouts are all "corrected" to some standard. They should all read pretty close provided they haven't been
dicked with. I think we pretty much know whos #'s to be skeptical of. And NO I'm not going to spell it out. You know
who you/"they" are)

[Don D]

Error is just that, it goes both ways and we keep trying to cram these results into some data of" significant accuracy. Forget it," accurate inertia dyno" is an oxymoron. Bias and human factors are driving these suto internet "case studies"

[Matt C]

 

If the stack is calibrated and software up to date, DynoJets all read within a percent or two.
I can dyno one here and take it over to my tuner, his dyno reads the same as mine.

[Admiral Akbar]

If the stack is calibrated and software up to date, DynoJets all read within a percent or two.
I can dyno one here and take it over to my tuner, his dyno reads the same as mine.

You are lucky.. The 2 happen to be close..Since they are close they should stay close..  There are a number of dynos that are off some amount.. It's not a statistical error either, it's fixed error caused by improper drum mass calibration.. The problem is that the drum is a big steel pipe filed with some kind of cement. Since the cement isn't consistent in density the rotation mass needs to be calibrated.. That is one of the reasons why each dyno should has a calibration file that is supplied with the dyno.. It include the serial number, diameter, drum mass, and a couple other constants..  People can screw with em.. Heck any half decent hacker can decode the stuff and make it whatever they want.. Early days most shops didn't have a 'puter nerd.. It's becoming more common. Dynojet figured out that they screwed up and started placing the drum constants in the embedded controller that came out with the winpep 8 upgrade.. Still there are dynos that were miss calibrated at the factory..

[Matt C]

You're exactly right Bruce. You have to intentionally jack with them to skew the numbers. There are Two other
tuners in our group (4 dynos counting mine all on WinPep 7) and we're all within a couple of percent.

I had my stack upgraded/calibrated about a year and a half ago and I'll probably get it checked out again this
summer when the battery needs replaced.

Added: The factory keeps records of the drum mass/serial number. That's part of the calibration process from what I
understand. That's why DJ makes you register your serial number with them. At least they try to keep people honest.

[Matt C]

I had a friend/customer come down from Chicago last summer with this "i gotta big dick" dyno sheet from a shop
up there.

So we decided to run it on our "lie detector" to see if there's some magic tricks I didn't know about. We got much
'more realistic' numbers than what he had been sold. Still pretty decent I have to say, just not the "i can't believe
it's not butter" stuff he brought with him.

So, yeah. Aparently there's allot of dodgy crap going on out there.

[1FSTRK]

Same guys with the same stories polluting another thread.
for all the posting you do you may want to learn to use this.

[Admiral Akbar]

Same guys with the same stories polluting another thread.
for all the posting you do you may want to learn to use this.

This thread is already polluted, diluted, convoluted, mooted, rooted, fluted, looted, disputed, constituted, persecuted, substituted, prostituted, and suited for ignoring..

[bigpete1]

What does Vic think about this scenario as you are going to have him do the work and tuning ? That is the question

[1FSTRK]

What does Vic think about this scenario as you are going to have him do the work and tuning ? That is the question

I have not been able to talk this over with Vic in any detail; he has been busy so far this year and only said that if we could wait he would be happy to work something up. I have based most of my questions on conversations I have had with him over the development of other combinations and honestly that is why this has been such a drawn out thread. I started it thinking that there would be many graphs posted and we would just pick one of them. Early on it became clear that most of the stock DBW throttle body builds are just not that efficient when you consider the work and money spent. There have been a few promising graphs and we thought we had two or three options for heads but as the questions became more specific the answers became more general. You have to sort through but there is some real information in this thread for anyone thinking of this type of build and there is more to come.

[1FSTRK]

Here is a little back ground video to get everyone up to speed before we get to some useful data.

https://www.youtube.com/watch?v=Ac7G7xOG2Ag
 

[wfolarry]

He would fit right in here.

[1FSTRK]

He would fit right in here.

Would be willing to bet a couple of these guys are blood relatives.

[Admiral Akbar]

Bet there are also some like these guys also.

https://www.youtube.com/watch?v=o2zNPVHBmeU

[1FSTRK]

Some are qualify as both.