Thread: How to make your fuel and timing maps AKA "TP/LOAD" scales

What happened to the rest of the data? This pull ends at 5,800 RPM but you were WOT all the way to at least 6,600 RPM and that is where you can really tell the difference.
Please post that?
You've chopped the data to hide the discrepancy.

So in this example you would be treating 110 TP as if it were 157 kPa. To use UNISA JECS's technique. Yet you would have to admit that you could legitimately see 157 kPa as early as 95 TP or as late as 115 TP, is that not correct?

Ben, you're right, you can't use one to calculate the other exactly, but Mr. JECS is right in that they trend together and can be "ball-parked" for his purposes of getting a general indication of where off-boost, boost transition, and on-boost are in his fuel map. That's all he and, VAD, and JK are saying.

loving this thread.... !

Dave, I'll concede that.

My main issue with this is that it is not technically correct, and following from that, it is used as a crutch that will prevent a tuner from understanding the intricacy, brilliance, and selling points of TP all while preventing them from learning how to tune with it instead of against it. One will always be stuck in a speed-density or simplified speed-density frame of mind when tuning with TP, which for me seems like a recipe for mediocre tunes at best and unsafe tunes at worst.


There is no reason to know or care what pressure you idle with, or where 100 kPa is, or where your max boost pressure is when working with TP. There is no reason to care about pressures at all, ever. Trying to put pressure into the mix is a sign to me that someone hasn't grasped what TP is all about. If one is to tune with mass air, I'd say it would behoove them to understand it intrinsically and quickly ditch any attempt at relating it to speed density. If I were teaching someone how to tune with mass air, I would never mention pressures, whether they were a novice or already familiar with speed density. I believe it would only confuse the matter, and send them down the wrong path.

Just to be clear Mr. JECS has changed what he was saying. Originally he said XX TP was always XX PSI/InHg and that the only reasons it wouldn't were noise or sensor delay.

I really want to clean this thread up because it was good until it spun out of control over a technicality then became good again.

I vote to NOT have this cleaned up Nate! Although there is some mud slinging, there is plenty good info in the arguments and debates!

Leave the thread, and let it continue. If someone else wants to, they can always stick their neck out and make their own thread about how they would recommend tuning a mass air setup. (And maybe have to defend it as well.)

Earlier he said he had delay... If that is true ALL rows of the MAP sensor data should be shifted to correct. That picture sure looks like somewhere around 0.2 second delay.

I meant to clean up the technicality witch hunt into a concise post rather than 2 pages... Whatever... I leave it unless OP wants it cleaned.