I heard the pros and cons about using the p72. But will i not be in trouble if i get my v-afc tuned to give me more fuel where the p72 starts to lean out? I'm getting it tuned soon just wondering if i should stick with the p72 or pick up a p13. I've seen really good number with the p72 and would like to use it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LvSi95 &raquo;</TD></TR><TR><TD CLASS="quote">I heard the pros and cons about using the p72. But will i not be in trouble if i get my v-afc tuned to give me more fuel where the p72 starts to lean out? I'm getting it tuned soon just wondering if i should stick with the p72 or pick up a p13. I've seen really good number with the p72 and would like to use it. </TD></TR></TABLE>
I'm interested in this too, specifically tunning out the fuel differences with the VAFC... Please help us guys. Thanks

 

Search. The only reason to use the p72 is for its Hondata compatibilities and additional features. You want to be running on h22a maps, not p72 maps. Running an unmodified p72 on an h22 is dangerous.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by miff &raquo;</TD></TR><TR><TD CLASS="quote">Search. The only reason to use the p72 is for its Hondata compatibilities and additional features. You want to be running on h22a maps, not p72 maps. Running an unmodified p72 on an h22 is dangerous.</TD></TR></TABLE>
Ok, so it is dangerous to run STOCK fuel maps on a p72, what if you tune the heck out of it with a vafc and FPR? I can use hondata on cheaper ECU's, the reason for using a p72 is the higher redline, and the fact that it controls seccondaries.

at first I was almost pissed to see that you told me to search, but I can't help but agree with ya

 

The only thing about the P72 is the secondaries. Remember, the Hondata will let you change the RPM limit along with speed limiter etc, so saying "the reason for using the p72 is the higher redline" is actually incorrect when compairing to another ECU with the hondata.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mattmw88 &raquo;</TD></TR><TR><TD CLASS="quote">
Ok, so it is dangerous to run STOCK fuel maps on a p72, what if you tune the heck out of it with a vafc and FPR? I can use hondata on cheaper ECU's, the reason for using a p72 is the higher redline, and the fact that it controls seccondaries.

at first I was almost pissed to see that you told me to search, but I can't help but agree with ya </TD></TR></TABLE>

 

DONT DO IT WITHOUT A HONDATA!!!!!!!!!

 

yes it's not smart to runa p72 stock on an h22a. search bitch. In the essential links I specifically explain why it blows

 

This are the two best posts ..... read them allllllll

https://honda-tech.com/zero...age=2

https://honda-tech.com/zerothread?id=612831

 

Why exactly is the p72 dangerous in stock form??? Is it because of the injector duration or what.?? I know it was desiged for a 1.8 motor but on a 2.2 motor it will be using 2.2 sized injectors not 1.8 size so where is the danger of running lean???

 

Picture this: Honda engineers design cars . When those engineers design the fuel and timing maps for a specific ECU, they tailor them to a specific motor with a specific fuel pressure and a specific injector size and a specific compression, etc etc.

Now you want to run the same maps on a completely different motor with different injectors, fuel pressure, and displacement etc

I don't know what fool started the idea that a stock P72 on a prelude motor makes more power, but I'd like to slap the **** out of them.......

Remember that the VAFC doesn't "give you more fuel" or give you less fuel.....it changes the load that the ECU sees via the MAP sensor, thus putting you in a different fuel/timing section of the map on the ECU (which fools the ECU into giving more/less fuel based on the map transition).....when you change the base fuel pressure, it totally changes the amount of fuel delivered throughout the powerband because injector flow is not linear (ie you're not adding a constant amount of extra fuel across the powerband)...this is also the reason that FMU's suck *** and are very difficult to "tune" properly......
B

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Firedrake &raquo;</TD></TR><TR><TD CLASS="quote">I don't know what fool started the idea that a stock P72 on a prelude motor makes more power, but I'd like to slap the **** out of them.......B</TD></TR></TABLE>

It was importbuilders. You could get better peak numbers with a V-AFC and your midrange wouldn't suck

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by satan_srv &raquo;</TD></TR><TR><TD CLASS="quote">

It was importbuilders. You could get better peak numbers with a V-AFC and your midrange wouldn't suck</TD></TR></TABLE>

I was over at that shop for some dyno day (I was in Cali visiting a friend at UCSD and another friend that works at AEM)......IB had a "shop car" up on the dyno trying to do something with it (not sure if it was tuning or what) while it was puking coolent.....needless to say, I was REALLY unimpressed.
I'll look for pix, I'm uploading a new video to our shop site right now though
B

 

When I said:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mattmw88 &raquo;</TD></TR><TR><TD CLASS="quote">
Ok, so it is dangerous to run STOCK fuel maps on a p72, what if you tune the heck out of it with a vafc and FPR? I can use hondata on cheaper ECU's, the reason for using a p72 is the higher redline, and the fact that it controls seccondaries.

at first I was almost pissed to see that you told me to search, but I can't help but agree with ya </TD></TR></TABLE>
I was simply saying that yes, we have established the point that it is unsafe to run stock p72... no ****.

My next question still goes unanswered... "what if you tune the heck out of it with a vafc and a FPR?" - I meant if someone did that then could they adjust it approprietly...
And finally when I said that I could run hondata on cheaper ecu's is simply to say that an alternative to the stock P72 is the addition of Hondata, renduring the fuel problem solved.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rjr162 &raquo;</TD></TR><TR><TD CLASS="quote">The only thing about the P72 is the secondaries. Remember, the Hondata will let you change the RPM limit along with speed limiter etc, so saying "the reason for using the p72 is the higher redline" is actually incorrect when compairing to another ECU with the hondata.
</TD></TR></TABLE>
We are referring to stock ecu's as far as using only a VAFC.
My additional comment was that
I was right with the most important thing, the seccondaries, but again, if you were to use a stock P72 like <U>he</U> ask originally then you might potentially want a higher red line, like that of a GSR as apposed to a stock Civic P28, which i assume has a noticably different redline(?).
Things you should factor: seccondaries, redline, Vafc, Hondata, price.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Firedrake &raquo;</TD></TR><TR><TD CLASS="quote">
Remember that the VAFC doesn't "give you more fuel" or give you less fuel.....it changes the load that the ECU sees via the MAP sensor, thus putting you in a different fuel/timing section of the map on the ECU (which fools the ECU into giving more/less fuel based on the map transition).....when you change the base fuel pressure, it totally changes the amount of fuel delivered throughout the powerband because injector flow is not linear (ie you're not adding a constant amount of extra fuel across the powerband)...this is also the reason that FMU's suck *** and are very difficult to "tune" properly......
B</TD></TR></TABLE>
So when it richens the motor gets fuel into the cylinders more rapidly(or in bigger quantities?) right?
So is it impossible to tune with FMU if you change everything fuel related as I have? I can post my graphs and you can see the a/f curve with my setup as I tuned for the first time.

Damn that was a huge post..

 

Like said before the vafc doesnt do much to the ecu. And if you are gonna spend 300 on a vafc why dont you just spend 280 on a hondata and do it right!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">My next question still goes unanswered... "what if you tune the heck out of it with a vafc and a FPR?" </TD></TR></TABLE>
All the vafc tuning won't change the fact that the ignition curve is for an engine other than an H22. The stock p72 is worthless for the H22.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 95 lude &raquo;</TD></TR><TR><TD CLASS="quote">Like said before the vafc doesnt do much to the ecu. And if you are gonna spend 300 on a vafc why dont you just spend 280 on a hondata and do it right!</TD></TR></TABLE>

I got a VAFC for free so that was why I went that route. Thanks guys for all your help, now I KNOW I won't be getting a p72 unless it's hondata. I assume that If I got hondata then I will still need to buy a new ecu, bringing the total to more then 300...
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sharkcohen &raquo;</TD></TR><TR><TD CLASS="quote">
All the vafc tuning won't change the fact that the ignition curve is for an engine other than an H22. The stock p72 is worthless for the H22.</TD></TR></TABLE>
I guess I should have known that, but thanks for the lesson...