Just wanted to show you guys some of the gains that we've achieved through tuning VAFC's. They are a competent unit and very easy to use, but also very easy to get wrong.

Graph #1 is my car after 15 straight runs, and very hot (210+degrees), vs 170 degrees for the first run.


The second graph is after 1 hour of tuning:


The third run represents a VAFC running FAR TOO MUCH fuel on the first run, and the subsequent fix and gains after the fact.


All in all, the VAFC is a good unit for most bolt on upgrades and mild cams.

 

Nice numbers/work. Hardly see anyone posting dyno sheets with a VAFC tune. Props

 

nice numbers, i'm planning on using a vafc to tune my fuel maps only.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris_Bye &raquo;</TD></TR><TR><TD CLASS="quote">nice numbers, i'm planning on using a vafc to tune my fuel maps only.</TD></TR></TABLE>

As opposed to what. It will ONLY do that anyway.

 

nice.. but i personaly dont think vafc's are the way to go..

here's my reason..

vafc works by modding the voltage coming from the MAP sensor..

in the ecu, both fuel and ignition tables use the Map sensor output voltage to calculate which column the table is being read from... anyway.. you modify your map output to make the ecu think the car is running rich or lean (whatever may be needed to acheive your a/f ratio) .. but it also changes your timing because your Ignition tables are affected by the map sensor...

ive got a buddy with a b20vtec.. 184 whp with 156 torque.. it should be pushing alot more but he's obd0 and opted to run vafc instead.. with obd1 ecu conversion and proper tuning both IGN and fuel... it will do ALOT better.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Speedz &raquo;</TD></TR><TR><TD CLASS="quote">nice.. but i personaly dont think vafc's are the way to go..

here's my reason..

vafc works by modding the voltage coming from the MAP sensor..

in the ecu, both fuel and ignition tables use the Map sensor output voltage to calculate which column the table is being read from... anyway.. you modify your map output to make the ecu think the car is running rich or lean (whatever may be needed to acheive your a/f ratio) .. but it also changes your timing because your Ignition tables are affected by the map sensor...

ive got a buddy with a b20vtec.. 184 whp with 156 torque.. it should be pushing alot more but he's obd0 and opted to run vafc instead.. with obd1 ecu conversion and proper tuning both IGN and fuel... it will do ALOT better.

</TD></TR></TABLE>


If you addfuel via an FPR, and then remove fuel with the VAFC, the gains are more substantial.

 

this is my before/after sheet with V-AFC tuning. These are crank horses, not wheel.

Pretty good!

 

Nice numbers Chris. The Vafc is a good unit imo with the fact of how fast you can tune a car but at the same time I would like to see how much you could gain by running an s300 system, neptune, etc. See what the end results would be.

 

I gained 10whp peak and 8 ft/lb tq peak just by switching from a VAFC to a Hondata unit.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LsVtec92Hatch &raquo;</TD></TR><TR><TD CLASS="quote">I gained 10whp peak and 8 ft/lb tq peak just by switching from a VAFC to a Hondata unit.</TD></TR></TABLE>

yeah that is exactly what I was looking for. Do you have your dyno graphs so we can see?
i know in terms of tuning the VAFC its fairly fast which is a huge plus but I would like to hear what some of the limits of it are compared to the other program out there.

 

The VAFC is a great unit for somebody not looking for the complexities of a stand alone. In my experience, you can bolt on all of the great parts you want, but getting them to work in conjunction requires TUNING. This is a graph I'm particularily proud of, as it is a totally stock GSR with lots of $$$'s spent on good quality bolt ons.



I think it gained 11whp peak, and more power everywhere. I just tuned a Saturn Coupe with an SAFC, and even though he only had an intake and muffler, we were able to get a solid 3-5whp gain everywhere, and 8+whp right at redline.

I'd love to play with more Hondata units, but as far as bang for the buck goes, the VAFC's are hard to beat.

 

i wont argue on the matter of it being quick, easy.. but i still think that the affect of modding MAP signal isnt good on the ignition table...

that b20vtec in my earlier post, totally built.. b16 head, ported, M22 cams, RM valvetrain, skunk2 cam gears, b20 block with GSR block girdle mod(yes mains were line honed) custom length eagle rods, wiseco 11.8:1 pistons (with raised wrist pin) (rod/stroke = 1.58) balanced bottom end.. AEBS IM, 70mm TB, RMF Narrow B header..

the worse thing about that setup is he's got obd0 pr3 ecu with mugen rom (to disable KS and o2 sensors)

he should be making ALOT more than 184 whp.. the tq is nice tho.. ( i havent seen the dyno charts on it) he got it tuned at Import Specialty Automotive in Tacoma, WA.. they added fuel with adjustable FPR.. and used vafc to pull it out..

oh well.
i think he should convert to obd1 and let me tune it with crome

 

i dont understand, im trying to read and learn.... but i still need some practice and reading...

 

How does this ( the A'PEXi V-AFC ) compare to the GReddy e-Manage or the new GReddy e-Manage Ultimate system? Anyone have any dyno graphs or stories with the GReddy devices?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Speedz &raquo;</TD></TR><TR><TD CLASS="quote">i wont argue on the matter of it being quick, easy.. but i still think that the affect of modding MAP signal isnt good on the ignition table...

that b20vtec in my earlier post, totally built.. b16 head, ported, M22 cams, RM valvetrain, skunk2 cam gears, b20 block with GSR block girdle mod(yes mains were line honed) custom length eagle rods, wiseco 11.8:1 pistons (with raised wrist pin) (rod/stroke = 1.58) balanced bottom end.. AEBS IM, 70mm TB, RMF Narrow B header..

the worse thing about that setup is he's got obd0 pr3 ecu with mugen rom (to disable KS and o2 sensors)

he should be making ALOT more than 184 whp.. the tq is nice tho.. ( i havent seen the dyno charts on it) he got it tuned at Import Specialty Automotive in Tacoma, WA.. they added fuel with adjustable FPR.. and used vafc to pull it out..

oh well.
i think he should convert to obd1 and let me tune it with crome </TD></TR></TABLE>

tell ur friend to defintily convert to OBD1 and run something like CROME,UBERDATA,HONDATA,NEPTUNE, etc

i tuned a completely STOCK bottom end B20 motor with a 1st gen B16 head w/ Skunk2 Stg 2 cams on uberdata and it made 185whp and 136 ft-lbs
with a built bottom end this car can see over 200whp easy. imo standalones are wayyyyy better than VAFc's

 

i cant complain, i like my vafc for 150 bucks.

 

Hondata, Crome etc. aren't stand alones persay. But yeah that built B20V should be making more power.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Speedz &raquo;</TD></TR><TR><TD CLASS="quote">i wont argue on the matter of it being quick, easy.. but i still think that the affect of modding MAP signal isnt good on the ignition table...

that b20vtec in my earlier post, totally built.. b16 head, ported, M22 cams, RM valvetrain, skunk2 cam gears, b20 block with GSR block girdle mod(yes mains were line honed) custom length eagle rods, wiseco 11.8:1 pistons (with raised wrist pin) (rod/stroke = 1.58) balanced bottom end.. AEBS IM, 70mm TB, RMF Narrow B header..

the worse thing about that setup is he's got obd0 pr3 ecu with mugen rom (to disable KS and o2 sensors)

he should be making ALOT more than 184 whp.. the tq is nice tho.. ( i havent seen the dyno charts on it) he got it tuned at Import Specialty Automotive in Tacoma, WA.. they added fuel with adjustable FPR.. and used vafc to pull it out..

oh well.
i think he should convert to obd1 and let me tune it with crome </TD></TR></TABLE>You can't blame that on the VAFC, I agree that Hondata is better but not so much that using a VAFC would leave his power numbers so low. I had a 84.5mm ls/vtec with 11:1 CR, ITR cams, ITR intake manifold, stock B16a head and a DC 4-2-1 header and made 191/143. This was on an OBD-1 ECU and VAFC. So there is something else wrong with your friends set-up.

 

These graphs were just to show how easy it is to make power with a VAFC.

The Emanage is a more complete unit. They are VERY good when used in conjunction with an E-01 boost controller.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Team 4 &raquo;</TD></TR><TR><TD CLASS="quote">These graphs were just to show how easy it is to make power with a VAFC.

The Emanage is a more complete unit. They are VERY good when used in conjunction with an E-01 boost controller.</TD></TR></TABLE>

howmuch power did you pick up on Nicks NX with this setup last week in what an hour and half on the dyno? something like 60whp everywhere.

 

60 from the base, and 40whp after the initial emanage setup. That is one quick NX2000. 280whp and only 2500lbs to push around.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Team 4 &raquo;</TD></TR><TR><TD CLASS="quote">60 from the base, and 40whp after the initial emanage setup. That is one quick NX2000. 280whp and only 2500lbs to push around.</TD></TR></TABLE>

you think it weighs 2500? i was thinking more like 2000lbs without driver. He has it gutted pretty good

 

Lots of glass in that car, and structural bracing for the T-tops.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Speedz &raquo;</TD></TR><TR><TD CLASS="quote">nice.. but i personaly dont think vafc's are the way to go..

here's my reason..

vafc works by modding the voltage coming from the MAP sensor..

in the ecu, both fuel and ignition tables use the Map sensor output voltage to calculate which column the table is being read from... anyway.. you modify your map output to make the ecu think the car is running rich or lean (whatever may be needed to acheive your a/f ratio) .. but it also changes your timing because your Ignition tables are affected by the map sensor...
</TD></TR></TABLE>

ah I see...so when you lean out your mixture with the vafc, are you in effect advancing or retarding the ignition, which one? I assume advancing is better for high rpm?

 

when u lean out on the VAFC u in turn have the timing advanced