Recap of the SAI circuit - Page 2 - Rennlist - Porsche Discussion Forums

Notices

Recap of the SAI circuit

Old 09-14-2011, 11:04 AM
  #16  
ltc
Super Moderator
Needs More Cowbell

Lifetime Rennlist
Member
 
Join Date: Mar 2002
Posts: 29,318
Default

If anyone needs electronics help with their prototypes, please feel free to PM me (I've been doing electronics for 40 years)

It would also be a very simple task to design a very quick and inexpensive printed circuit board (probably around $5 + parts) which would make assembly much easier...sort of like an old Heathkit.
ltc is offline  
Old 09-14-2011, 11:26 AM
  #17  
michaelh993
User
 
michaelh993's Avatar
 
Join Date: Mar 2009
Location: Behind the Zion Curtain
Posts: 106
Default

please please!
michaelh993 is offline  
Old 09-14-2011, 12:41 PM
  #18  
tonypai
User
 
tonypai's Avatar
 
Join Date: Apr 2008
Location: Chicago, IL
Posts: 274
Default

Lewis

If you decide to make the boards, I'd be interested.

Tony
tonypai is offline  
Old 09-14-2011, 01:19 PM
  #19  
ltc
Super Moderator
Needs More Cowbell

Lifetime Rennlist
Member
 
Join Date: Mar 2002
Posts: 29,318
Default

Is there a specific size the PCB should be?
Would an assembled board be better than a bare board/bag of parts? I know some people don't like to solder.

I took a quick look at the schematic and it looks OK, I would perhaps make some minor changes.
(I designed OEM electronics for Porsche, Audi, Mercedes so working on a 12V automotive bus is something you don't forget)

I could probably do something like this on a rainy weekend, send the files out to have boards made (usually 1 week) and assemble a few in my basement electroncis shop.
ltc is offline  
Old 09-14-2011, 01:45 PM
  #20  
fullbooker
User
 
fullbooker's Avatar
 
Join Date: Dec 2006
Location: Auburn, CA
Posts: 388
Default

Lewis,
I would be very interested in purchasing one of these boards for my car, also. Can I give you a "deposit?"
Thanks,
Phil
fullbooker is offline  
Old 09-14-2011, 02:16 PM
  #21  
NP993
Addict
Rennlist Member
 
NP993's Avatar
 
Join Date: May 2001
Posts: 3,053
Default

I would also buy a board. Just so things are clear -- this enables us to physically remove the SAI system from our cars, including the OBDII ones, and never have a problem with getting smogged/CEL's?
NP993 is offline  
Old 09-14-2011, 02:29 PM
  #22  
tonypai
User
 
tonypai's Avatar
 
Join Date: Apr 2008
Location: Chicago, IL
Posts: 274
Default

Originally Posted by ltc View Post
Is there a specific size the PCB should be?
Would an assembled board be better than a bare board/bag of parts? I know some people don't like to solder.
That's me!

A pre-assembled board would be fantastic. Installing it in the car would be piece of cake.
tonypai is offline  
Old 09-14-2011, 03:14 PM
  #23  
ltc
Super Moderator
Needs More Cowbell

Lifetime Rennlist
Member
 
Join Date: Mar 2002
Posts: 29,318
Default

I don't mind doing the PCB layout and soldering/assembling the boards.
I am not looking to make any profit from this, so it would just be cost + shipping.

I will double check with the Admin (Bob) to make sure there are no issues.
ltc is offline  
Old 09-14-2011, 03:25 PM
  #24  
flying_low
User
Thread Starter
 
flying_low's Avatar
 
Join Date: Oct 2004
Location: East Bay, CA
Posts: 588
Default

Originally Posted by NP993 View Post
I would also buy a board. Just so things are clear -- this enables us to physically remove the SAI system from our cars, including the OBDII ones, and never have a problem with getting smogged/CEL's?
That's correct. You would no longer see SAI errors but other CELs unrelated to SAI are still possible which is a good thing.
flying_low is offline  
Old 09-14-2011, 03:31 PM
  #25  
flying_low
User
Thread Starter
 
flying_low's Avatar
 
Join Date: Oct 2004
Location: East Bay, CA
Posts: 588
Default

Originally Posted by ltc View Post
Is there a specific size the PCB should be?
Would an assembled board be better than a bare board/bag of parts? I know some people don't like to solder.

I took a quick look at the schematic and it looks OK, I would perhaps make some minor changes.
(I designed OEM electronics for Porsche, Audi, Mercedes so working on a 12V automotive bus is something you don't forget)

I could probably do something like this on a rainy weekend, send the files out to have boards made (usually 1 week) and assemble a few in my basement electroncis shop.
I would imagine soldered components would be best for most. I'm interested in a couple as well.

One variant I did from the schematic, is the 12v ground wire was connected to the chassis directly instead of the gray O2 sensor lead just to make it more convenient.
flying_low is offline  
Old 09-14-2011, 03:45 PM
  #26  
ilko
Agent Orange
Rennlist Member
 
ilko's Avatar
 
Join Date: Jun 2006
Posts: 15,738
Default

I'll take one too, Lewis. Thanks for the offer!

That being said I can see how this easily could turn into a 100+ unit job so if you decide to outsource it I would be more than happy to cover the costs. I'm sure most people here would be too.

Thanks again!
ilko is offline  
Old 09-14-2011, 04:42 PM
  #27  
ltc
Super Moderator
Needs More Cowbell

Lifetime Rennlist
Member
 
Join Date: Mar 2002
Posts: 29,318
Default

A question on wire termination options.

1. soldered wires, say 12" long, coming off the board
or
2. use screw terminal blocks, allowing you to chose wiring type/length/etc...no soldering required (they are fairly inexpensive), just a screwdriver
Example:
http://search.digikey.com/scripts/dk...name=A98036-ND

It would be the same PCB, in the first case, I simply don't install the terminal block and solder wires instead.

I have sent a PM to the Admin and IB, just to make sure there is no conflict of interest (I am not a RL sponsor and not doing this for a profit... more of a hobby).

Once I hear back, I will likely setup a seperate thread to keep track of who would like the PCB. It will be small enough to be sent via USPS (which should keep costs down)
ltc is offline  
Old 09-14-2011, 04:50 PM
  #28  
600RR
User
 
Join Date: Jul 2010
Location: South Bay Area
Posts: 988
Default

I'm in for a soldered board. Suggest $10 if Lewis does it for $5 (but only $5 if Larry does the work underground), BTW, Heathkit? Wow, that was awhile ago.
600RR is offline  
Old 09-14-2011, 04:51 PM
  #29  
600RR
User
 
Join Date: Jul 2010
Location: South Bay Area
Posts: 988
Default

Forgot to add ... Thanks for stepping up on this. Very nice.
600RR is offline  
Old 09-14-2011, 04:51 PM
  #30  
MDamen
User
 
MDamen's Avatar
 
Join Date: Jun 2007
Location: Redmond, WA
Posts: 628
Default

Thanks for doing this Lewis. Looks like there is lots of interest.

I would suggest soldered wires coming off the board. That makes it one less step to install and I don't have to think about what kind of wires I want to use. The users who want a very specific wire and length will probably change it anyway.

Are you thinking of providing boards with components installed, just a board, board and kit of parts, or all three variations?

Other posts have brought out concerns of liability if the circuit should cause some problem to their car. You may want to provide a kit of parts with instructions and let the builder accept responsibility. I don' tknow the interface to the ECU and what the possibility is of ECU damage if a short to ground or short to hot should occur.
MDamen is offline  

Thread Tools
Search this Thread
Quick Reply: Recap of the SAI circuit


Contact Us About Us Advertising Cookie Policy Privacy Statement Terms of Service

© 2018 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: