I did some searching and found some basic answers but I would like a real hard nosed opinion on this. And please don't scold me if this answer has already been posted.

I have a Vishnu flash, and I know it would be better to get another flash than just to do an SAFC. Here is my question. I have seen several Evo friends get mad power out of an AFClike 400whp with no flash and no stand alone or piggy back.

Will an SAFC help me achieve maximum power with the flash? Or should I flash back to stock and start over with just a SAFC.

Since timing has been pulled with my flash I figure an SAFC should only benefit me but I could be wrong. Please give me your honest opinion......and I am not getting another reflash (unless back to stock) and I am not doing a piggyback or stand alone.

THank you so much for your help.

 

well if ya run an Safc u are running a piggyback as it tied into the stock ECU...just sold my emanage to give the safc a shot...we will see

 

Just to be clear, the S-AFC is a piggyback.

To answer your question, I think you will definitely benefit more from adding an S-AFC to your flash than flashing back to stock then tuning from scratch with the S-AFC. The flash + S-AFC combo is superior to both by themselves. You will be able to optimize your AFR/Timing on top of the flash for any circumstance - change in boost, temp, humidity, octane, additional mods, etc. You will need to get a datalogger, too, though.

 

Thank you Warrtalon. I meant to clarify a piggy back such as a UTEC or larger piggyback system....not just an A/F ratio.

Now once I have the SAFC installed, and then tunned you are saying that I will need a datalogger too? What kind of data logger should I use and how do I use it? What's the importance of it?

Sorry...probably simple questions from a person who is learning as he goes.

 

No, you will need a datalogger IN ORDER TO TUNE IT, not after it's tuned. The datalogger will show you what your AFR and timing is, and then you will adjust your fuel settings based on these logs. I only use a very simple pocketlogger based off free software and an old Palm M100, but this is only narrowband. It's best if you install a wideband O2, then get a logger that can read this wideband O2 and other parameters. You then adjust the S-AFC settings (leaner or richer) until you get the desired timing curve (near-linear increasing to 19-20 at redline) with a good AFR in the 11-11.5:1 range.

 

Thank you so much for your help. One last question. The guy who is tunning it is doing it on a dyno, and he tunes it by playing with the AFC and getting the A/F ration to a good point be reading the screen or logger he uses. Is that acceptable. He tunes a lot of Evo SAFC around here. I am guessing his dyno and computer IS the datalogger.??

 

That's not good enough. Yes, he will be "logging" the wideband AFR, which is good, but there's more to tuning than AFR. Sometimes, the optimum AFR does not result in the optimum power gain. Of course, being on a dyno helps you get the best power, but it's the TIMING that really tells the story. Unless he has his own logging device other than the AFR sniffer (or whatever he uses), then he won't be able to ensure a smooth and aggressive timing advance.

*** ALSO, you don't want to run around with an S-AFC that has been tuned by someone else on a dyno, because conditions change and you HAVE to know how to adjust them according to different situations, otherwise you just have some static settings that worked while stationary on a dyno at a specific temp/humidity/octane/boost level. If this is ok with you, and he does a fairly conservative tune, then I don't think you will gain much over just the flash itself. If you really want to make the most of the S-AFC and your mods, then you would need your own logger then make sure everything is kosher when actually driving on the road with proper airflow and road conditions that can't be mimicked on a dyno. Also, you would want the flexibility to adjust for different times of year as the temp/humidity change and if you ever get bad gas or or want to toss in higher octane for racing.

If you aren't going to tune this youself, I recommend sticking with a flash (custom road tune) and not spending the extra money on the S-AFC + dyno tuning costs. It's up to you, though, because there is definitely some gains to be had, although they won't necessarily be big gains...

 

Thank you. That's the kind of answer I have been looking for. I will probably let him get an initial tune on it, but then I will research it myself and start to tune myself as I learn more. But if he starts me off with a decent tune, and I can always work form there. Thank you again so much for your help. I will just have to keep searching the web to find the best way to tune it and why. Cause I have the concept of the A/F ratio but I know that there is more to it than just that. I am also scared of tuning it out myself and hurting the engine. I will just read and learn and then take it from there.

Any suggestions of where a rookie can start to learn about tuning an AFC efficiently?

 

just wanted to subscribe

 

Yes, I have a very good resource that you and others may want to use for strictly tuning purposes:

EvoTuners (just like DSM Tuners)

There is an S-AFC II install guide along with a detailed S-AFC II tuning guide (can be used for S-AFC I, also). This is where I learned everything and is what I use as a basis for my tuning.

 

Oooh, thanks for the link to the other site Warrtalon.