Fast, Accell or BS3

[quickt]

Originally posted by HighPSI
Timing is timing, and pulse width is pulse width regardless what computer is sending the signal. Perhaps, Lonnie or DFI guy could explain.

Cal,
I am not sure I can explain it. It seems to me that the Gen7 WBO2 works to correct much faster and more accurite than the FAST. I HAVE NO PROOF OF THIS. I have noticed with the FAST the closer you get to 0 correction the more power you tend to make. I have tuned the same car with the Gen7 and had similar power as the FAST at 1-2% and the Gen7 at 10-12% correction and ofcourse the closer I was to 0 even more power was made. The FAST seems to be affected more by the swing of the 02 as the fueling changes seem to be slower to me allowing the actual AF to be more off the target. I have had a FAST that would be pig rich in hi gear and when you started working the VE table to get it close then WOW it would be lean accross the board. I have never seen this with the Gen7. Same with timing. I set the base timing with the Gen7 and what the screen says I have with a very stable timing mark when checked with a timing light. I have seen the FAST after the timing was set then checked with a timing light the mark would be moving all over the place. In my opinion from what I have seen I think the Gen7 has a more accrite fuel delivery with more stable timing. Again I have no proof other than my observation. I also have been able to get the cylinder EGT balance much closer than I could with a FAST. In Chris Lyons case we were able to balance within 30deg in 3 pulls on the dyno making even a little more TQ & HP. I also see small gains with the injection timing v/s Intake valve timing. Like I said these are my observations I have no rock solid proof. It would neat to do both systems on the same car to see if they are both the same or if one can really edge out the other. I dont know if there can be a clear winner. If a engine is in tune it does not matter. Like I said earlier I know the Gen7 much better than I know the FAST. So ofcourse I am going to get better results from a Gen7.

 

[JoyOf6]

Originally posted by HighPSI
I have to agree with Jack on this one (Did I say that!?! ).

I thought I saw a flying pig this morning... was worried the medication stopped working until I read this.

 

[BoostKillsStres]

Lonnie, very good points. The fuel tuning you speak of is the exact type of thing I went thru in creating/tuning my WB controlled chip. You want to make fuel changes slow enough and small enough so you don't swing back and forth across the target wildly once you get there and also not have rich and lean spikes on the shifts but you need changes to happen fast enough to be able to correct for conditions and to get you on target quickly.

So, no simple free lunch, you have to find a happy medium that works for a large spread of vehicles and I'm sure all 3 systems have their own routines for control. Which one is best at it, probably never know, will be like the eternal IC debate, since who's gonna spend all the money and time to swap and run multiple dfi systems on a single vehicle on the same day to try and determine which is best. Maybe data from best run et/mph for a car over several sessions w/ different units will someday surface and should be interesting.

 

[aDFIguy]

I have seen some "shootout" type situations where a shop will put a combo on their engine dyno, then invite manufacturers of different engine management systems to send their tuner of choice to install their system and see what they can get out of it. Being that it's an engine dyno, things can go on and off pretty quickly, so some of these tests take place all in one day.

The differences that I have seen are usually quantified in 10's of HP -- enough to be attributed to the management system and not written off as atmospheric/temperature/etc influences. Since the tuners are handpicked by the manufacturers, there are no excuses to be made for inexperience or lack of understanding with the controller.

What I'd love to see is someone try to do something similar in multiple vehicles simultaneously where driveability/acceleration/idle... differences could be quantified. We almost had one of the OEMs talked into it for crate engine testing, but they shot it down at the last minute.

As for why the differences, think about why a Gen 7 is better than a Gen 6... It's a much more accurate model of what is really going on with the engine, and doesn't necessarily boil down to just timing and PW. It's a completely different tuning process because of the mathematical modelling that it involves. It relies on the tuner knowing more about the situation so that they can provide the controller with the very accurate information that it needs. As the old saying goes, garbage in => garbage out. Some people take to it pretty quickly and in return, get some great results. Others just don't pick up on it and prefer something else.

 

[norbs]

On a different topic, can you explain the advantage and the strategy behind the boost builder option found on the gen 7?How can this decrease spool time , compared to not using this feature?