Need O2 clamp for EMU - 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 01-23-2008, 08:49 PM   #1
Newb
Thread Starter
 
Join Date: Mar 2006
Location: Fremont, CA
Posts: 5
Total Cats: 0
Default Need O2 clamp for EMU

Hey folks, I meant to post in this thread: https://www.miataturbo.net/forum/showthread.php?t=13232

... but it seems you've cleaned old threads/posts and my post count has gone to 1, so I can't post in the marketplace area.

I'd like to ask Joe Perez if he can make those or share the documentation so I can make my own.

Thanks!
Intruder is offline   Reply With Quote
Old 01-24-2008, 08:51 AM   #2
Junior Member
 
Join Date: Apr 2007
Location: Melboure australia
Posts: 171
Total Cats: 0
Default

ive sent joe a pm, waiting for a reply, i have an older guy one if you want that.....
sprx3 is offline   Reply With Quote
Old 01-24-2008, 12:12 PM   #3
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: 26,318
Total Cats: 1,916
Default

Hey, guys.

I've decided to stop building these, as it's more trouble for me than it's worth. As requested, I'm re-posting the schematic for my EMU-triggered O2 clamp here so that everyone can build their own if they want one. Perhaps some kind mod will sticky this so people can find it more easily in the future.

The resistor values are not absolutely critical. If you have to sub a 4.7k instead of a 4k it's no big deal- it'll just shift the centerpoint on the potentiometer a little. A note about the pot itself, I much prefer to use the more expensive box-shaped 15 or 20 turn units as opposed to the cheap single-turn units. You need a lot of precision when setting this resistor, and a multi-turn makes it a lot easier to set.

The diode across the relay can be damn near anything that isn't a Zener. I've been using 1N4004s simply because I have a pile of them. Use something that has a 1N400x number and you'll be fine.

The regulator probably doesn't need a heat-sink. It's only passing a few ma.

The trigger output of the EMU is 12v. Since I'd been using 5v relays (again, I had a few extras) I had to put a resistor in series with the coil. If you use a relay rated for 12v you can jumper across this resistor.

Instructions for setting up the EMU are here: http://miatajoe.50megs.com/O2_Clamp.pdf
Attached Images
File Type: gif O2Clamp.gif (49.0 KB, 311 views)
Joe Perez is offline   Reply With Quote
Old 01-24-2008, 07:02 PM   #4
Newb
Thread Starter
 
Join Date: Mar 2006
Location: Fremont, CA
Posts: 5
Total Cats: 0
Default

Excellent! Thank you!
Intruder is offline   Reply With Quote
Old 01-24-2008, 07:23 PM   #5
Newb
Thread Starter
 
Join Date: Mar 2006
Location: Fremont, CA
Posts: 5
Total Cats: 0
Default

Quick question, might be dumb but I'll ask anyway...

Most modern cars have 2 oxygen sensors. Why do we clamp only one (1st / front). Is it the only one being used for closed loop fuel trim adjustment? What effect does the 2nd / rear O2 sensor have?
Intruder is offline   Reply With Quote
Old 01-24-2008, 07:27 PM   #6
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,867
Total Cats: 1,790
Default

nothing, the second one simply tells the ecu if the cat is working.
Braineack is offline   Reply With Quote
Old 01-24-2008, 07:47 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: 26,318
Total Cats: 1,916
Default

Yup. it's one of those sensors whose sole job in life is to help you fail a smog check by throwing a CEL when it determines that the catalytic converter is no longer functioning efficiently of if its own heater goes out. Gotta love OBD-II.
Joe Perez is offline   Reply With Quote
Old 01-28-2008, 02:56 PM   #8
Senior Member
iTrader: (2)
 
Join Date: Aug 2007
Location: North Cackalackey
Posts: 716
Total Cats: 2
Default

i got one of those clamps that joe built and the thing is flawless. worth the money i definitely would not be able to build on like that. sad to see you are not building them any more great product.
musanovic is offline   Reply With Quote
Old 01-29-2008, 03:50 AM   #9
Junior Member
 
Join Date: Apr 2007
Location: Melboure australia
Posts: 171
Total Cats: 0
Default

if anyone wants one ive built two, (as most parts were only available in pack form) so if you want one yell out !!!!
sprx3 is offline   Reply With Quote
Old 01-29-2008, 11:00 AM   #10
Senior Member
 
Join Date: Jun 2006
Location: Orlando FL - UCF
Posts: 688
Total Cats: 1
Default

Me!!!
coastertrav is offline   Reply With Quote
Old 01-29-2008, 11:01 AM   #11
Senior Member
 
Join Date: Jun 2006
Location: Orlando FL - UCF
Posts: 688
Total Cats: 1
Default

oh but by judging by your location I can only imagine shipping... :(
coastertrav is offline   Reply With Quote
Old 01-29-2008, 05:34 PM   #12
Junior Member
 
Join Date: Apr 2007
Location: Melboure australia
Posts: 171
Total Cats: 0
Default

anyone that wants it, give me your post code & i'll work out shipping before you decide on it, something like this is usually 10-30$ depending on how fast you want it....
sprx3 is offline   Reply With Quote
Old 01-29-2008, 06:20 PM   #13
Senior Member
 
Join Date: Jun 2006
Location: Orlando FL - UCF
Posts: 688
Total Cats: 1
Default

nah, I will just go ahead and make one.
coastertrav is offline   Reply With Quote
Old 04-19-2013, 02:54 PM   #14
Newb
 
Join Date: Apr 2013
Posts: 1
Total Cats: 0
Default

I really need one of these!! Can you guys help me out?
Thanks!
malanga31 is offline   Reply With Quote
Old 04-19-2013, 03:44 PM   #15
Senior Member
 
Join Date: Apr 2011
Location: Martin, Slovakia
Posts: 513
Total Cats: 71
Default

https://www.miataturbo.net/e-manage-...ll-help-65812/

You can make one for < 10$ using a dpdt relay and a couple of 5k variable resistors.
sturovo is offline   Reply With Quote
Old 05-12-2013, 10:30 PM   #16
Newb
 
Join Date: May 2013
Posts: 2
Total Cats: 0
Default

Are people using this with AF sensors or narrowband sensors?

Excellent work either way.
evilthorne is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Another Cast Manifold Corky Bell Prefabbed Turbo Kits 18 11-22-2016 10:01 PM
The deezums Catch Can aidandj Engine Performance 138 10-31-2016 02:32 PM
Worm drive clamps are better than t-bolt clamps aidandj Insert BS here 80 09-18-2015 08:19 PM
Annoying little leaks AlwaysBroken Engine Performance 5 09-06-2015 01:53 AM
15 psi and EMU Red Roadster Prefabbed Turbo Kits 6 11-16-2006 05:36 PM


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 02:49 PM.