BaschBoost SmartMAP

[cobalt]

I have just received a BaschBoost SmartMAP "thingy" from MJ at Dali Racing (Thanks for the verrry fast shipping, Mark!), for use on my NA 1995 NSX-T - I don't have a blower on the car.

Now, my reasoning for using it on my NA NSX is this:

I have removed the O2 sensors on my NSX (all four of them), so fuel metering is now performed by the MAP sensor, and fine-tuned with an Apex'i Super AFC. I am tuning my air flow signal higher at some points along the rev band for more power, due to better flow into the TB and more efficient cylinder excavation from the headers and Taitec JGTC exhaust (many thanks to Chris at ScienceofSpeed!)...

My theory (not really a theory...just a hunch), is that if I tune the air flow to a point that is outside what the OE ECU considers to be a "valid range" with the Apex'i unit, that the ECU is fooled into thinking there is a temporary boost condition...

Sometimes (1 out of 50 times, perhaps?), when accelerating through high rpm's...my injectors will lock open...literally dumping fuel into the engine...bogs it down...sputters fuel out the tailpipe...until I shut off the ignition and restart it...then all is fine.

I am hoping the SmartMAP takes care of this...because I won't track my NSX anymore until this is resolved, as having power cut out around a WOT sweeper will spin the car...not safe.

Any thoughts? Or am I puffing on the magic dragon?

-Andie

 

[Andrie Hartanto]

Andie,

Just curious, why not put the O2 sensor back?

 

[Andrie Hartanto]

Andie,

Just curious, why not put the O2 sensor back?

 

[cobalt]

Cuz ma cha don't not wanna run too good with dem in dere...

<grin> -Andie

The car stumbles and bogs down and hesitates and does a bunch of weird-*ss stuff with the O2 sensors in place...go figure...happened after a header install...

-Andie

 

[true]

unless you are tuning using a dyno or a wideband unit, you are much better off putting your stock o2's back in. SAFC is just a TOY without _accurate_ A/F datalogging. Your theory seems to be ...strange. Tuning the airflow??????....How do you know your injectors are 'locking' open..does SAFC show duty cycle? My advice would be throw the stock o2's in there untill you get legit aftermarket fuel management or get tuned using professional devices.

 

[true]

Originally posted by HomeDepotNSX:
Cuz ma cha don't not wanna run too good with dem in dere...

<grin> -Andie

The car stumbles and bogs down and hesitates and does a bunch of weird-*ss stuff with the O2 sensors in place...go figure...happened after a header install...

-Andie

Hrm, did you ever think maybe you had a bad o2? Are the o2 bungs in the same place as the factory exahust?

 

[cobalt]

Originally posted by true:
Hrm, did you ever think maybe you had a bad o2? Are the o2 bungs in the same place as the factory exahust?

Yup...$850 dollars worth of O2 sensors later...the car stumbles, etc. with O2 sensors...and about $1000 in tech time later...

Car runs strong as p*ss without O2 sensors...

-Andie

 

[true]

Are the o2 bungs in the same place as the factory exahust?

 

[cobalt]

Originally posted by true:
Are the o2 bungs in the same place as the factory exahust?

Bingo! You win!

That's what I suspect...the O2 sensors that normally go on the exhaust manifold have been moved to the collector on the new headers...that maybe the problem...but I don't wanna drill a header primary tube...we'll see...

-Andie

 

[sjs]

As I recall, the stock O2 sensors are only addressed under high vacuum and should have no effect within a blink of an eye of starting hard acceleration. They are for idle, cruising, and light acceleration as in EPA tests.

 

[true]

Originally posted by sjs:
As I recall, the stock O2 sensors are only addressed under high vacuum and should have no effect within a blink of an eye of starting hard acceleration. They are for idle, cruising, and light acceleration as in EPA tests.

Yep, you are correct...sounds like his symptoms..he said it ran like crap with the o2's in.. (normal drivability) this is called closed loop..open loop is when it reads straight of the static fuel/timing maps on the ecu. I _think_ over ~3500RPM, and WOT is the switchover to open loop operation. Moving the factory o2's is like moving a stethascope and still listening for a heartbeat. On my crx, the factory o2's were plumbed into the stock manifold in 2 places on the 4-2-1 exhaust manifold....1 o2 went to cylinder 1 and 3 where it comes together, the other on 2 and 4. If you simply REVERSE them, it will sputter at cruising speed, smell like gas etc.. it really amazed my how sensitive they were...it's the exact same sensor..but each one ran a pair of cylinders. I datalogged the reversed o2's and found that it ran each pair of cylinders 25% rich, the other 25% lean. I feel your pain because after I put on my custom 3" turbo downpipe i could do nothing but just guess on where the o2's went..it ran like junk in closed loop...luckily my ecu allows me to disable closed loop. There's a reason these japaneese and custom race exahausts dont have o2 bungs....they don't use the stock fuel managment when they run them.

By the way Andie..don't you get a check engine light cause of the unplugged o2's? Honda/Acura ecu's dont see boost..if the MAP goes +, you get a check engine light and it may die depending on the conditions.

------------------
jack of all trades, master of some.


[This message has been edited by true (edited 05 March 2002).]

 

[ak]

If the settings on the VAFC under wide and narrow throttle have been set beyond +12~14% at any point, it will cause the ECU to believe that the car is under boost. This will trigger the MAP sensor error.

That's what Apexi says.

 

[NSXTech]

Andie, If you don't mind me saying, its a bit nutty using the SmartMap without forced induction. As the guy who designed the item, I have to tell you it was never designed to run on a NA NSX. If you had / have drivability issues immediately following a header install, someone botched it!. The most common problem after header install is a pin backing out of a connector for the O2 sensor, causing a check engine lite, at the very least. You don't say if you had one or not- surely you have one with no O2's at all and as someone here mentioned, driving around with the lite on is a *BAD* idea.

If you want to tune your car with an aftermarket devise like the Apexi controller, you need to leave in all the sensors that are part of the stock system- it is what the designers of the controllers had in mind when they designed them. It is very unlikely that you have the skills or the knowledge to do a better job of combining components and / or their settings than the designers of those components. No insult intended, really. What you are doing is actually rather dangerous- it is very likely that you have too much fuel flowing and in fact too much fuel is as bad as too little- it's just a few miles more before the big meltdown, but meltdown you will. Too much fuel washes the oil from the cylinder walls, creating a condition called cylinder wash.

Back to the smartmap for one last comment- it was only designed to keep the map from seeing boost- without this eventuality, you are getting no benifit at all- the smartmap only works when it see's the vac signal go to max, or about 2.75v, at zero vac. With the map working normally in an NA car, you can't do any better than what it already does.

I would reccomend removing the devise.
Cheers,
Mark Basch

 

[sjs]

Originally posted by NSXTech:
... Back to the smartmap for one last comment- it was only designed to keep the map from seeing boost- without this eventuality, you are getting no benifit at all- the smartmap only works when it see's the vac signal go to max, or about 2.75v, at zero vac. With the map working normally in an NA car, you can't do any better than what it already does.I would reccomend removing the devise.
Cheers,
Mark Basch

Mark, it sounds like this would replace the vacuum switch and solenoid that closes the vacuum line to the map sensor under boost on my TT. If so, what benefit might I get over the present arrangement?

Perhaps I'll buy the one from you HomeDepotNSX.

 

[true]

Originally posted by NSXTech:
It is very unlikely that you have the skills or the knowledge to do a better job of combining components and / or their settings than the designers of those components. No insult intended, really. What you are doing is actually rather dangerous-

Hrm, I dont know...in another thread he was claiming to be able to 'tune out' the advantage of better front/rear stabalizer bars (nsx-r) by lowering tire pressure..and spring rates.

Sorry....had to do it, but yeah drill/tap up your new exhaust and put your damn o2s back in. You'll see added torque in closed loop operation..which is non-existant now.

------------------
jack of all trades, master of some.

 

[true]

Originally posted by sjs:
Mark, it sounds like this would replace the vacuum switch and solenoid that closes the vacuum line to the map sensor under boost on my TT. If so, what benefit might I get over the present arrangement?

Perhaps I'll buy the one from you HomeDepotNSX.

Sjs, I don't think you will get any advantage at all. The smartMAP is just a little cleaner version of what you have. Mark can correct me if I'm wrong, (having never seen one) but I believe it would replace the map sensor completely. The factory map sensor is basically just a multimeter. The purpose of the sensor is to convert the amount of VACUUM into a voltage and feed that to the ECU. Notice I stress vacuum because if it goes positive at all (boost) the stock ECU throws an error code 3 and a pretty little check engine light. Lots of poor Honda turbo tuners use check valves connected in parallel to 'bleed' the boost off so the map doesnt see positive pressure(+). Check valves are about as bad as tuning with an AFC. Sounds like sjs's device is a mechanical check valve basically. It will give you the same results as the smartmap unless there is something more trick about it...

------------------
jack of all trades, master of some.


[This message has been edited by true (edited 07 March 2002).]

 

[sjs]

Originally posted by true:
Sjs, I don't think you will get any advantage at all. ...

Yea, pretty much the way I figure it as well except that I didn't get the impression it replaced the stock sensor, although it very well may, but it seemed worth asking. Even if it is effectively the same as what I'm using, I wouldn’t mind a tidier, cleaner solution.

 

[Runutzzzzz]

The Smart Map does not replace the MAP sensor, I have one.

love it.

Anyways. It "Cuts" the sensor wire and ties in between, it modifies the signal IF it were to get a + PSI signal to make the ECU
"think" that it was at 0 vac.

 

[true]

Originally posted by sjs:
I didn't get the impression it replaced the stock sensor, although it very well may, but it seemed worth asking.

Good call...now that I think about it, I don't know why I figured it replaced the stock map. It's much easier to make a unit that only meters and modifies voltage then build a pressure sensor vacuum port into it. oops.



------------------
jack of all trades, master of some.

 

[cobalt]

Mark,

Yes, I'm at the same point as before when the headers were installed. I replaced all the O2 sensors, and had a 2nd and 3rd tech check all the connections, and they said they were just fine...but the car still didn't run well.

Do you think the placement of the O2 sensors at the header collector would be a problem? Would you recommend tapping a primary on each header and installing the O2 sensors there?

I'll put the SmartMAP on my shelf of spare Dali Racing parts...I have a small collection of things I buy but never use...nice to look at when I'm sitting at my computer, and MarkJ appreciates it, I'm sure.

No offense taken...I'm not very knowledgeable about engine work...I only know about brake pads. That's why I posted this thread and asked!

The part about tuning the suspension...what I said about that is true...you can tune how the car handles (oversteer/understeer tendencies) with sway bars, spring rates, shock dampening rates, tire pressure, and even tire compounds... You can also affect how a car handles under trail braking with different compounds. So I didn't appreciate that jab.

Thanks for all the information, Mark.

-Andie

[This message has been edited by HomeDepotNSX (edited 08 March 2002).]

 

[cojones]

Were you able to try it with the cats back on ?? Does using test pipes on an OBD-II car further complicate things?

 

[NSXGOD]

Originally posted by HomeDepotNSX:


< snip >

The part about tuning the suspension...what I said about that is true...you can tune how the car handles (oversteer/understeer tendencies) with sway bars, spring rates, shock dampening rates, tire pressure, and even tire compounds... You can also affect how a car handles under trail braking with different compounds. So I didn't appreciate that jab.

Thanks for all the information, Mark.

-Andie

Hi Andie,

here's something from the "other" Mark:

A "handling tuning" chart:
http://www.daliracing.com/v666-5/info/camber.cfm

------------------
need more info? please private me @

[email protected]

Mark Johnson, CEO of Custodial Services @ Dali Racing, a Not For Profit Company.

 

[BryanZublin]

Sorry if this is late, I don't check the Forum that often...

> ...it sounds like this would replace the >vacuum switch and solenoid that closes the >vacuum line to the map sensor under boost >on my TT. If so, what benefit might I get >over the present arrangement?

You would be replacing two electromechanical devices and vacuum lines with a single solid state device. Guess which one will be more reliable?

There is not much "trick" about the SmartMAP. It simply clamps the MAP voltage to the ECU so the ECU does not "see" boost and turn off the injectors. The MAP sensor itself is not modified. It is only useful for boosted applications.

More details on the Dali web page.

Bryan Zublin

------------------
Zublin Engineering
http://www.zublin.com

 

[sjs]

Originally posted by BryanZublin:
Sorry if this is late, I don't check the Forum that often...
Bryan Zublin

Better late than never!

I'm wondering if my present solenoid arrangement is responsible for a serious problem with my car. Under WOT acceleration in a given gear the car does not ping. However, if I shift hard to the next gear detonation comes on instantly and hard. If I lift briefly then roll it back in everything is OK until the next shift.

This was not a complete surprise to me because I have had similar problems with old turbo systems and traced it to too much advance and/or too little fuel for various reasons. So now I have a much more advanced engine, but the turbo setup required same rather crude alterations. First there are the auxiliary injectors which are driven by a combination of boost and RPM. Upon shifting both these momentarily fall off dramatically, then the boost immediately comes on harder than before the shift while the engine speed is obviously lower. Since a hard shift represents a moment of sever load, and therefore high fuel demand, it’s a very bad time for the auxiliary injectors to be caught sleeping.

Even if I crank up the mixture dramatically (well beyond what is safe) the problem persists. There is no practical means to increase fuel only for that first instant after shifting without far more sophisticated mapping. But even if I could that may be missing the real cause of the problem. Now I’m wondering if it may be a problem with either the vacuum switch or solenoid failing to respond quickly enough, allowing the MAP sensor to see boost. Hmmm… sounds like a possibility and I can probably test it without too much effort.

Any other ideas?

 

[NSXTech]

Originally posted by sjs:
Better late than never!

I'm wondering if my present solenoid arrangement is responsible for a serious problem with my car.
Any other ideas?

The smartmap *might* help, if in fact the current arrangemant that you have (you don't say what that is) is causing a reaction delay in fuel caused by delay in map output.
If whatever devise protects your map now; I assume some type of check valve and alternative path restrictor arrangement, is too slow to respond, I can forsee a situation where boost develops quickly under the sudden accel you describe, and the map sees the beggining of boost so it greatly lowers the output from the map. That is the risk with the mechanical solution to map/boost- it almost always has a delay of somesort because mechanical devises do. Depending on what devise(s) you are using, this delay may be greater under some conditions than at others. That is the primary reason I designed the smartmap with
Bryan Zublin- predictability / reliability.

I know you know this, but let me say it anyway because it is SOOooo important- don't drive a boosted motor with detonation. It WILL be fatal.

Cheers,
Mark Basch