Which MAP sensor to use - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


E-Manage Post your questions about greddy e-manage installation and tuning here.

Reply
 
 
 
LinkBack Thread Tools
Old 01-20-2008, 10:35 PM   #1
Junior Member
Thread Starter
iTrader: (2)
 
Join Date: Dec 2005
Location: San Jose, CA
Posts: 124
Total Cats: 0
Default Which MAP sensor to use

There are TONS of MAP sensors out there. Is there one that I should be using? I know that KAGS1969 uses a GM 2 BAR (part #213-1520), but all of them seem to be the same. For example:
http://cgi.ebay.com/GM-2-BAR-MAP-SEN...QQcmdZViewItem
Comes with a plug, but references a different GM# (16009886). Both are 2 BAR sensors.

Tony
amagalla is offline   Reply With Quote
Old 01-20-2008, 11:16 PM   #2
Elite Member
iTrader: (24)
 
Join Date: Jul 2007
Location: Cypress, TX
Posts: 3,778
Total Cats: 35
Default

GM 2 bar is what I use.
Bryce is offline   Reply With Quote
Old 01-21-2008, 04:11 AM   #3
Junior Member
Thread Starter
iTrader: (2)
 
Join Date: Dec 2005
Location: San Jose, CA
Posts: 124
Total Cats: 0
Default

The problem is that both the one that Kags used and the one in the link are 2 BAR sensors with different GM part numbers. How do I know what to get and what to use in the software?

Tony
amagalla is offline   Reply With Quote
Old 01-21-2008, 10:04 AM   #4
Elite Member
iTrader: (24)
 
Join Date: Jul 2007
Location: Cypress, TX
Posts: 3,778
Total Cats: 35
Default

Well, the one in the link right there looks exactly like mine. I'm pretty sure there is only one map sensor option in the software, Greddy Map sensor.
Bryce is offline   Reply With Quote
Old 01-21-2008, 10:58 AM   #5
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

There are a couple of MAP sensors listed in the software's Front Panel config, but none of them have any scalings listed and nobody (myself included) has ever gotten off their **** and reverse-engineering the settings to see what they are.

A lot of folks are using off-the-shelf 2 bar MAP sensors. There are quite a lot of them out there, and they're all pretty much the same. Problem inherent in these is that you wind up having to print out the chart that Olderguy posted in the Archives which correlates MAP to voltage out of the 2bar, and doing all your tuning in volts rather than PSI. Kinda annoying. Also note that 2bar sensors typically scale from 0-5V, whereas the input of the EMU seems only to scale from 0.5 - 4.5V, so you lose some range at the very top and bottom of the sensor, theoretically maxing out at 11.6PSI.

My personal recommendation- you've come this far, pony up the $99 and buy the official Greddy 4 bar sensor.
Joe Perez is online now   Reply With Quote
Old 01-21-2008, 11:30 AM   #6
Elite Member
iTrader: (24)
 
Join Date: Jul 2007
Location: Cypress, TX
Posts: 3,778
Total Cats: 35
Default

Only one setting here. :(

I'm running v1.49.
Attached Images
File Type: jpg pressure sensor.JPG (88.0 KB, 126 views)
Bryce is offline   Reply With Quote
Old 01-21-2008, 12:33 PM   #7
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

Quote:
Originally Posted by Bryceness View Post
Only one setting here. :(
Oh. OP didn't specify EMU vs. EMB. I sometimes forget about the differences.

Within EMU, selection for Greddy (4-bar) sensor:


Selection for "Factory Pressure Sensor" which opens a second window for a whole arseload of sensors that I couldn't find specs for:



Love that new avatar.
Joe Perez is online now   Reply With Quote
Old 01-21-2008, 12:39 PM   #8
Elite Member
iTrader: (24)
 
Join Date: Jul 2007
Location: Cypress, TX
Posts: 3,778
Total Cats: 35
Default

Thanks Joe!

I sometimes kick myself for getting EMB instead of MS, Emu, etc.

I wonder how many people have noticed the new avatar. Maybe I should make it less subtle.

Last edited by Bryce; 01-21-2008 at 07:58 PM.
Bryce is offline   Reply With Quote
Old 01-21-2008, 07:51 PM   #9
Senior Member
iTrader: (7)
 
Join Date: Mar 2005
Location: VT
Posts: 939
Total Cats: 0
Default

Motorola 2.5Bar - MPX 4250AP- I ran all 3 of my EMB's off one. (til I added the profec then I only had 2 EMB's running them You can pick them up cheap at DIYautotune or Glensgarage.com

Glen only charges a few bucks for shipping and ships fast

http://www.glensgarage.com/catalog/2...nsor-p-60.html
Jefe is offline   Reply With Quote
Old 02-03-2008, 12:04 AM   #10
Newb
 
Join Date: Mar 2006
Location: Fremont, CA
Posts: 5
Total Cats: 0
Default

So is there really no substitute for the Greddy sensor? Can't use any of the MAP sensors and tune by "boost" instead of voltage levels?
Intruder is offline   Reply With Quote
Old 02-03-2008, 01:15 AM   #11
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

Yes, you can use any MAP sensor you want so long as you have the conversion chart of pressure to voltage taped to your dashboard and are willing to do all your tuning in volts rather than PSI.

The caveat is that the 4-bar Greddy (which presumably you'll be scaling to) goes from 0.5v to 4.5v, whereas most MAP sensors go from 0v to 5v. So you lose some range at the extreme ends of the scale. When I first attempted the AFM removal I was running a 2 bar sensor and could not make it work.

I guess I look at it this way- the Greddy sensor is $100. A 2-bar is typically $40. Is saving $60 really worth all the hassle you're going to endure for as long as you own the car?

Spend the money and get the right sensor.
Joe Perez is online now   Reply With Quote
Old 02-06-2008, 10:31 PM   #12
Senior Member
iTrader: (7)
 
Join Date: Mar 2005
Location: VT
Posts: 939
Total Cats: 0
Default

Quote:
Originally Posted by Joe Perez View Post
Yes, you can use any MAP sensor you want so long as you have the conversion chart of pressure to voltage taped to your dashboard and are willing to do all your tuning in volts rather than PSI.

The caveat is that the 4-bar Greddy (which presumably you'll be scaling to) goes from 0.5v to 4.5v, whereas most MAP sensors go from 0v to 5v. So you lose some range at the extreme ends of the scale. When I first attempted the AFM removal I was running a 2 bar sensor and could not make it work.

I guess I look at it this way- the Greddy sensor is $100. A 2-bar is typically $40. Is saving $60 really worth all the hassle you're going to endure for as long as you own the car?

Spend the money and get the right sensor.
What hassle?

I have been using 2.5 sensors for years.... then I discovered it was the same one used in MS... Maybe the EMU has some, but the EMB is too dumb to know the difference
Jefe is offline   Reply With Quote
Old 02-07-2008, 11:35 AM   #13
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

Quote:
Originally Posted by Jefe View Post
What hassle?
Having to deal with MAP in terms of volts rather than kPa or PSI.
Joe Perez is online now   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 57 07-19-2017 05:11 PM
My solution for Oiltemp and Oilpressure input into Megasuirt (MS3) Zaphod MEGAsquirt 41 01-24-2016 01:25 PM
Back to Stock Part Out!! Turbo Parts, MS2 Enhanced 01-05, Suspension, and MOAR! StratoBlue1109 Miata parts for sale/trade 16 10-02-2015 10:39 AM
In need of base map for stock 1997 brandonbkd MEGAsquirt 0 09-29-2015 12:52 AM
Got bad Crank Angle Sensor and Random Misfire codes, but runs fine. Greasyman General Miata Chat 2 09-28-2015 11:44 AM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 09:11 PM.