I'm looking for dyno results for a VAFC on a B18B or B20B with stock internals.

Please let me know what mods the car does have if possible. Thanks!

 

None really. The way it operates is counterproductive for increasing power.

 

How so? It changes the signal from the MAP to alter the fuel added by the computer at WOT when you're in open loop no?

With VTEC there are 8 points to adjust along the RPM range for low cam and 8 for high cam. With non-V I've heard of people using 16.

If you're leaning out at ~5.5k on a b18b1 with FPR tune (as I'm seeing) then you can lean it out up top too with the VAFC and make more power...

 

Holy moly. I saw this thread title and figured someone had to have bumped a thread from 2003.

You are way overestimating the importance of small fuel changes on power, especially on a stock engine. The difference between being "a little too rich" and optimal, is probably 1-2hp on this engine. Furthermore, by spoofing the MAP signal, you are also changing other things, like the ignition timing. By trying to lean it out, youll end up advancing the timing as well, which will most likely cost you power. Otherwise you could just advance the distributor and get the same effect.

Basically, throw the VAFC in the garbage where it belongs. There is a reason they call those devices bandaids, because theyre just a bandaid compared to proper ECU tuning, and because theyre AIDS. Say no to bandAIDS.

 

Take a look at an ignition map and consider what happens as you advance along the load axis... the ignition advance typically decreases. Also typically the ignition moves opposite of the fuel as you move around the maps... at MBT an engine typically finds its highest fuel demand and lowest ignition demand.

The VAFC intercepts the MAP signal and increases the load signal to add fuel and vice-versa. So when you add fuel with this method, you’re also pulling advance - and ignition is where the power comes from.

so yeah, “tuning” with a VAFC is counterproductive. That’s why no one uses them anymore.

 

I had a GSR engine blown up on the dyno years and years ago when i tried to have the engine tuned with it.. Lets just say i invested in a Hondata S100. You would be better off with a Etune or base map with Hondata.

 

​​​​Not many tuners are going to spend Dyno time and use a vafc unless that's their only option to tune your engine.

​​​​Using a vafc with a wideband o2 and street tuning a stock engine would be extremely helpful, better gas mileage, faster, all the good stuff us tuners are looking for. If I had to stay obd0 or obd2 I would definitely use a vafc for simplicity and cost. But if your obd1 and you plan on Dyno tuning go with crome....it's inexpensive and with the ability to advance timing you can run leaner fuel mixtures which...makes power.

 

You are a Tuner and you recommend CRomE ???

 

I doubt that he is a tuner.

 

So, you are saying I shouldn't have taken this statement literally ?

 

Awful advice.

 

Ooow.. I totally missed the "us" part..