... just like the topic says... is it possible to boost past ~11psi with the stock map sensor?... if so, how?... lemme know... thanks...

(( btw, no fmu/missing link/check valves comments please, i dont wanna go that route, thanks ))

 

i know you don't want to here about check valves,but that is the only way you are going to do it.you can take a borg warner check(#ec601) valve and put the vacuum side to vacuum and the blocked side to the map and drill a very tiny hole(small as possible) and you can make as much boost as you want.this way,the map sensor never sees boost.the reason you have to drill a hole is that if you don't the sensor will see no pressure at all.it has to see atmospheric pressure or it will throw a code.this way,it will be able to recieve full vacuum while not under boost and when boosted,it will be blocked from manifold pressure and be receiving atmospheric pressure through the tiny hole.you have to do a really small or you will have a big vacuum leak and it will idle very rich. i am using this on my wife's car and several customers cars and it works great.with or without an fmu.if you have bigger injectors and an afc it will work fine as well.

 

... thanks for the info!... but then, how would this work with the fuel and ignition maps?... assuming that i am running closed loop in boost, would i be forced to run off of maps for 11psi, regardless of how high i turn up the boost?...

 

the maps will be the same as if you are using the afc hack.on the hack you are changing the air flow signal to make the ecu think there is no boost.with this,you should not have to lower the signal to fool the ecu.you should be able to run more boost with the same injectors and fine tune it with the afc.

 

I can't believe I'm reading this.

OK, you can boost 10 million psi on the stock Honda MAP... but... hope you weren't planning on the stock MAP responding past 9.25 psi OBD0/10.65 psi OBD1/2. If you are looking for the MAP sensor to respond to pressure to control fuel + ignition, then 9.25/10.65 is your limit.

If you are looking to boost a couple psi over that limit and you have the injector, fuel pressure, or fuel maps that will allow it for your setup you can tune for over what the stock MAP can sense - you'll pass thru an overly rich area as you approach 9/10 psi and then pass into the tune you are shooting for. I don't think it's safe, streetable, or reliable... but I'd do it short term for a laugh or to try for a timeslip. Understanding what's going on is critical, IMO.

I fail to see how keeping the Honda MAP sensor from seeing boost will help a V-AFC hack which operates as a for of forced induction fuel control solely because the Honda MAP sees boost. Having it not see past atmospheric will not help a V-AFC boost hack setup. You will get NO under boost enrichment.

Having it not see past atmospheric, without V-AFC hack, for boost... unh... HUGE TIP IN PROBLEM there buddy. If (and I don't think it will, from experience) the Honda ECU will even tune enough fuel out under closed loop cruise; the map-based (not MAP sensor, literally "map," in the ECU) dwell the fuel correction code bases itself on will be stupid rich.

<-- Joseph Davis, posting under Todd's account.

 

hmm I boost 12.5 to 6000 rpm until my wastegate craps out and drops down to 10.5 and it never throws a code.

 

ok,maybe i should explain it like this.use dsm injectors,an afc,and the check valve.use the afc to trim the fuel at idle,cruise,and tune as much as 0% with no cel.run as much boost as you have fuel for.my point is,you don't have to trim the fuel down to trick the map sensor anymore.it works great!

 

hmmmmmmmhm, im running an afc hack with -36 all the way accross, and dsm 450cc injectors. I never throw a cel, and im pushing 12psi

 

I am thinking that all of you who say you can't boost over 9.25/11psi are full of crap. Have you ever tried it with a voltmeter hooked up to it? BoostedED9 went above 16psi and didn't throw a CEL, and many other people have gone ~1bar. Strangely, back in the day with my homebrew/filetofit MAP circuit experiments, I would throw a code at 9psi, but with the afc, I've run 13 or so...

I cannot verify that the MAP sensor is still responding, but A/F and EGT look good...

 

What are you guys talking about?? The stock honda map sensor cannot read boost at all. How can it read boost if it was never a turbo car.

 

turbotypeR... OK, I can see how that works, but I don't see it working that great. Get some wideband logs across the vaccum<-->boost range and see what I mean.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ion_four &raquo;</TD></TR><TR><TD CLASS="quote">I am thinking that all of you who say you can't boost over 9.25/11psi are full of crap. Have you ever tried it with a voltmeter hooked up to it? </TD></TR></TABLE>

Yes, I have. I can tell from your statement that you have not. I've posted what voltages 9.25/10.65 psi occur at in the past, feel free to verify my work when you find/buy/figure out to use your DVOM .

And if you spent four minutes thinking about what the AFC hack does, you'd understand how you can boost to greater than 9.25/10.65 psi without CEL 3. If the MAP sensor voltage, modified by your AFC cut %, never exceeds 3.0-3.1 volts I guess you don't EVER click a CEL 3.

Don't call crap when you haven't done the first thing to check the facts yourself. Don't worry about apologising to me about that, either, nobody ever does. Just take your spanking... the same one I've administered to about a zillion times and am getting bored with... and THINK about what the AFC hack does. Sit down and graph it out on a piece of paper - I have, it helps lots.

- Joseph Davis

PS: I really need my Agent Smith avatar to feel properly prickish.

 

^^wow, i was going to say, "Where's J. Davis. he knows all about this" and then i saw at the bottom of your post you're under a different account.

 

I'm visiting Todd/Overblown-Teg in PA, switching accounts back and forth is too much of a PITA.

We spent today finishing the SC61 and (built by him) tubular stainless turbo install on his GS-R today, tuned it with Uberdata. Runs pretty well. Some wideband tuning, finish fabbing my IC, and picking up more stainless els + a few hundred T3 flanges tomorrow. :&gt;

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SupaTeg &raquo;</TD></TR><TR><TD CLASS="quote">What are you guys talking about?? The stock honda map sensor cannot read boost at all. How can it read boost if it was never a turbo car.</TD></TR></TABLE>

The honda sensor is 2 bar, the sensor will read positive pressure, the ECU just doesnt know how to compensate for it. It does have a tollerance of a couple psi of positive pressure to deal with altitudes. The ECU technically doesnt read boost, but the with the AFC hack you are moving the map values down, allowing you to boost before you hit the ECU's map cutoff.

I could only boost 10.5psi on my b20/vtec (was -32%) and 65psi static fuel pressure.

jay

 

Exactly, SupaTeg, only the Honda MAP is 1.8 bar with 1.65/1.74 bar limitations. You've actually thought about this, and you're one of only FIVE I know of in the world.