Been doing more reading on Speed density (map) tuning, most of that has confirmed my initial impressions previous. Basically changing/calibrating the VE table any time a change is made.

Seems the biggest difference from a tuning aspect is that SD requires the VE table to be calbirated/tuned first, and the MAF tuning needs the MAF calibrated/tuned first.

After that most of the basis is the same, even calibrating the VE table is almost identical to how you calibrate the MAF signal. It's just way easier with the haltech to change the VE table, as MAF is a single Y axis table and requires direct imputs in all values.

Going to try and get some SD tuning attempts done tomorrow(ish), been hitting snags with my laptop.

 

You touched on an important point that many Uprev tuners still don't grasp in F/I tuning -- calibrating the MAF table before going onto the compensation tables. If checking your tune and you see anything on the compensation table more than +/- 5%, your MAF table isn't properly calibrated and the tune is questionable at best. I've seen maps where tuners are adding 10,20,30% in large sweeping blocks on the comp tables and wondering why it's great at WOT on the dyno but they have annoying hiccups on the street.

The only thing that pisses me off with MAF calibration in Uprev is no live tuning... you will spend considerable time and write cycles dialing it in properly so it doesn't surprise me many tuners (who want to maximize $$/hr) skip over this part and jump straight to the comp tables for live tuning.

 

Part of the reason I want to do this myself is just that, they're out to make money. To do this the way I want it done, to the quality I want would take too long. obviously this isn't true of all tuner's

if only I had a dyno!! lol.

As to the point of calibrating airflow before touching any other tables, that should be done regardless of N/A or FI, or the car, or whatever. that's always step one, and you're right, most guys dont. They jump at adjusting fuel first.

the haltech won't let me adjust MAF in real time, but MAP can be, yet another favoritism for MAP tuning with the Haltech. Oh well, I'll bite and try it that way if it's easier with this program I guess, as Binder eluded, why overcomplicate it.

 

You're right, it's also important with N/A however a VQ stock MAF is fairly well calibrated (within +/-10% in most cases) especially if you're using a stock intake tube. You can probably get away with leaving it alone and jumping straight to the comp tables.

Switch to F/I, Even on a stock MAF, simply adding a fuel return will throw the whole calibration off. Swap with an aftermarket MAF and you're starting from scratch (the tables included with Uprev are nowhere near reality due to differences between MAF's and fuel systems).

The good news is you can do a pretty good job tuning on the street. I had mine 100% there in vacuum and 90% there in boost before I put it on a dyno for max power adjustments.

 

Do you just tune to 'feel' or do you use accelerometers and knock to tune on the street mainly?

As for the MAF calibration, this is in the ECU, because I have a Haltech it relies completely on the Haltech's MAF calibration, which is off, hence my initial post in this thread. But yeah Osiris or stock ECU calibration is fine for sure get what you're eluding to now.

 

I never tuned for power on the street. I just set a conservative/safe timing map and got the A/F all dialed in, and listened with knock headphones to make sure there was no obvious knock. I drove it on this rough tune for almost a year and it made good power. When I finally put it on a dyno I increased timing and cam advance and netted almost 10% increase in peak power and lots of area under the curve.

 

Ya, you can get a lot of you driving map tuned on the street before renting a dyno. I usually do it that way for the vac map then do any small things left on the dyno before doing boost.

And yes, tuning the maf table was the longest part of tuning with osiris and drove me nuts having to shut down and restart.

 

There's ways to expediate that process. Things like if you make 3x 60% changes you can safely assume that the whole range is off 60%, change the whole thing to get closer.

Either way, it's a horrid PITA the way the Haltech has it set up. Even though there's more adjusting with MAP tuning, it's so much easier, and that seems to be the way to handle the Haltech as it's programming stands. Hopefully they'll change this to accomodate both avenues in the future.

 

ya, haltech VE tuning with map is pretty easy. The directd injection time is also easy.

If you hit the key Q or W (i can't remember which) while in a specific cell it will do an auto tune of that cell to make it meet the a/f in the target map. I don't use this feature but it's available for anyone that wants to use it. Works best on a dyno when you can hold a specific cell.

 

^ I found out about that during a crapload of reading and forgot all about it again!!! lol I'm going to try that and see how well it does. thanks for reminding me Bro

 

np, good luck in your tuning.