Adjustable Map Sensor

[import racer]

Hey did anyone see Trucks today on Spike.They were showing how to make an adjustable map sensor for 10-15 bucks,but i can't find anything about it on thier site.

[Pico]

I found this article, is it something similar to what you saw today
http://www.jeep-xj.info/HowtoMAPsensor.htm

[Oldblueaccord]

10K pot maybe ?



wp

[import racer]

Yeah something like that,had a small circuit board,a toggle switch and some resisters.Could something like that work on ours,or would we need to be OBD-1.

[cygnus x-1]

I found this article, is it something similar to what you saw today
http://www.jeep-xj.info/HowtoMAPsensor.htm

That's the one that was on Trucks. It would work on the 3g MAP sensor since it's also powered by 5V. Another way to accomplish the same thing would be to get an adjustable fuel pressure regulator.


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[import racer]

Oh Ok thanks,Is there anyway to tune a stock motor without going OBD-1.Something thats cheap.

[carotman]

And... what would be the benefit of an adjustable map sensor?

[mkymonkey]

thats funny, when i watched this i thought...i wonder if someone on 3geez would want to give this a shot

[cygnus x-1]

And... what would be the benefit of an adjustable map sensor?

Adjusting the MAP sensor changes the fuel mixture during open loop operation (WOT).


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[carotman]

Adjusting the MAP sensor changes the fuel mixture during open loop operation (WOT).


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Yeah but...

Oh well, I guess it works only on an A20A3 or similar engines where the computer doesn't control ignition.

If you have any other Ignition controlled ECU Honda, you can't do this.

The ECU will adjust the ignition timing according to the load value. This load is taken from the map sensor.

[cygnus x-1]

Yeah but...

Oh well, I guess it works only on an A20A3 or similar engines where the computer doesn't control ignition.

If you have any other Ignition controlled ECU Honda, you can't do this.

The ECU will adjust the ignition timing according to the load value. This load is taken from the map sensor.

True. It would adjust the timing as well if the timins is ECU controlled. An adjustable fuel pressure regulator would be better in that case. But then if your ECU controls timing then you probably have OBD1 anyway and could just tune that way?


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[carotman]

Yup.

For a second I forgot the A20A didn't have electronic advance.

In that case, the Adjustable MAP can be a good cheap alternative to a OBD1 conversion

[stephensimmons]

Or you could do like i did and get one of the older 5 knob apexi s-afc(you can get them for around 130.00 with shipping or cheaper if your patiant like me i got one for 80.00 shipped) and you can set the fuel from idle to 7200rpm. all it dose is adjust your map sensor at certain rpms with the dials.

[stephensimmons]

Yup.

For a second I forgot the A20A didn't have electronic advance.

In that case, the Adjustable MAP can be a good cheap alternative to a OBD1 conversion

Yes it could be EXCEPT you cant adjust your timming with your dizzy likeyou can with obd1 if you do the adjustable map and remain obo.

[2ndGenGuy]

No, you just undo the bolts and twist the distributor to retard / advance your timing?

[carotman]

This only changes the base timing. There are some areas you can have more or less timing depending on load and fuel mixture.

[stephensimmons]

No, you just undo the bolts and twist the distributor to retard / advance your timing?

Yes you can do that but i ment through timming maps in the ecu. With obo you can adjust the map sensor through the map in the ecu but the timming is through vaccum and springs and weights in the dissy. obd1 you can adjust your fuel map and timming through the ecu which makes it more accurate. Now if im wrong will some one plz correct me because i dont want to missinform anyone.

[stephensimmons]

If your trying to get more power I read on here and I cant remember the name of the thread but maybe someone else dose and if I find it ill post it but you can take the map sensor and the pigtail form a 4th and 5th gen accord and wire it into your harness and BUT hook up only one at a time and the 3rd gen one was for economy the 4th gen one gave you a little more power and the 5th gen one was even more power but you got less fuel mileage. Has anyone else read that?

I found it. Its in the How to section under engine/transmission then open up the DIY: multiple map sensor harness link.

[2ndGenGuy]

This only changes the base timing. There are some areas you can have more or less timing depending on load and fuel mixture.

So the 3gee distributor has dual vacuum AND electronic advance? I was talking stock distributor. Even changing the base timing though still changes the entire curve.

[stephensimmons]

So the 3gee distributor has dual vacuum AND electronic advance? I was talking stock distributor. Even changing the base timing though still changes the entire curve.

I think its just vaccum advanced thats why everyone goes to obd1 because you have no real control over your timing when you do serious modes exspecialy turbo.

[carotman]

Yeah it's vacuum controlled and has regular centrifugal advance. you can't fine tune it.

[cygnus x-1]

If your trying to get more power I read on here and I cant remember the name of the thread but maybe someone else dose and if I find it ill post it but you can take the map sensor and the pigtail form a 4th and 5th gen accord and wire it into your harness and BUT hook up only one at a time and the 3rd gen one was for economy the 4th gen one gave you a little more power and the 5th gen one was even more power but you got less fuel mileage. Has anyone else read that?

I found it. Its in the How to section under engine/transmission then open up the DIY: multiple map sensor harness link.

Yeah, there was this thought that you could swap MAP sensors and it would change the tuning. However some time back I compared 3 different Honda MAP sensors using a voltmeter and a vacuum pump. They all had identical MAP to voltage curves, so swapping MAP sensors gets you nothing. The ones I tested were from a 3g Accord, 4g Accord, and I think a B18A1 Integra.


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[MessyHonda]

Yeah, there was this thought that you could swap MAP sensors and it would change the tuning. However some time back I compared 3 different Honda MAP sensors using a voltmeter and a vacuum pump. They all had identical MAP to voltage curves, so swapping MAP sensors gets you nothing. The ones I tested were from a 3g Accord, 4g Accord, and I think a B18A1 Integra.


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i dynoed it and the 4th gen accord sensor got me 2 whp and 4 pounds of torque to the wheels.

[cygnus x-1]

i dynoed it and the 4th gen accord sensor got me 2 whp and 4 pounds of torque to the wheels.

How many runs did you do with and without the 4g sensor? Those are within the margin of error for the dyno. You can get that much variation from one run to the next without changing anything.


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