Electrical engineers, lets do this! - Page 2 - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


Everything Electrical & Electronic Have an electrical problem? Lighting, Alternators, gauges, DIC, HUD, etc? Post it here. Please post Audio problems in the Audio forum, and Engine control problems in the appropriate Mechanical forum for your year.

Reply
 
 
 
Thread Tools Search this Thread
Old 11-06-2004, 05:04 PM   #11
Senior Member
Certified Car Nut
Thread Starter
 
Join Date: Jun 2003
Posts: 15,928
Thanks: 0
Thanked 0 Times in 0 Posts
BonneMeMN is on a distinguished road
Default

If they're in Parallel then the POT will not give the same effect on all resistances..

I'm not pulling my o2 at all for many reasons, one of them being the fact that this is supposed to be on the fly.
BonneMeMN is offline   Reply With Quote
Old 11-06-2004, 05:16 PM   #12
Junior Member
Posts like a Ricer Type-R
 
Join Date: Aug 2002
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road
Default

Quote:
Originally Posted by BonneMeMN
If they're in Parallel then the POT will not give the same effect on all resistances..
With the pot (high value) in parallel, it decreases the overall resistance of the circuit. A 100k pot goes from 0-100k. This would be the perfectly simple way of accomplishing what you want.

At 100k, it wouldn't be affecting the IAT reading much, but as you drop the POT resistance, it does.
willwren is offline   Reply With Quote
Old 11-06-2004, 05:18 PM   #13
Senior Member
Certified Car Nut
Thread Starter
 
Join Date: Jun 2003
Posts: 15,928
Thanks: 0
Thanked 0 Times in 0 Posts
BonneMeMN is on a distinguished road
Default

Ok i see what you're saying now. Basically make the resistance terribly high so nothing would go through there anyways.
BonneMeMN is offline   Reply With Quote
Old 11-06-2004, 05:24 PM   #14
Junior Member
Posts like a Ricer Type-R
 
Join Date: Aug 2002
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road
Default

You got it. The higher the better. A 1meg pot will still go to 0.
Do the math to see how much the high end of each pot will affect the circuit resistance. You don't want this to affect normal driving at max by very much.
willwren is offline   Reply With Quote
Old 11-06-2004, 05:36 PM   #15
Senior Member
Certified Car Nut
Thread Starter
 
Join Date: Jun 2003
Posts: 15,928
Thanks: 0
Thanked 0 Times in 0 Posts
BonneMeMN is on a distinguished road
Default

What range would be best? I'm going to run 2 wires for this into the passenger compartment.

I don't like doing that math. I'm still in basic EET class.
BonneMeMN is offline   Reply With Quote
Old 11-06-2004, 06:11 PM   #16
Junior Member
Posts like a Ricer Type-R
 
Join Date: Aug 2002
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road
Default

My goof. I had the ratio on the temp/resistance backwards in my head.

When the IAT reads higher temps, the resistance is LOWER. In that case, you want to INCREASE the total resistance in the circuit.

-40F (and Celisus coincidentally) is 100k ohms. That'* the coldest value listed. For comparison, 212F is 177 ohms, and 59F is 4450ohms.

Add a pot in series with the IAT. Not in parallel. If it'* 95F outside, you are running at 1.8Kohms. By adding in about 2.6k, you can make it think it'* 59-60.

Adding in a 5K pot, cranked all the way would be 41 indicated.

There are some unknowns here. How much colder do you need the IAT to read? A 2.5k or a 5k pot would certainly do the trick. On another note, you don't really need a pot, but rather just a rheostat, although a pot can be wired as a rheostat, and by picking which tap you want, you can have it dial either clockwise or counter-clockwise to achieve your results.
willwren is offline   Reply With Quote
Old 11-07-2004, 09:19 PM   #17
Senior Member
Certified Car Nut
Thread Starter
 
Join Date: Jun 2003
Posts: 15,928
Thanks: 0
Thanked 0 Times in 0 Posts
BonneMeMN is on a distinguished road
Default

Oh yeah, all those ebay modules are inline resistors, more resistance = more power.

Ok a Rheostat.

41* of temperature change there? Hrm... Sounds close, I'm curious to see if anyone can log IAT temp/timing on a scantool. I think 5 degrees is all we would really need, and that'* pushing it, unless we'd like to use race gas.

Dame?
BonneMeMN is offline   Reply With Quote
Old 11-07-2004, 09:58 PM   #18
Junior Member
Posts like a Ricer Type-R
 
Join Date: Aug 2002
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road
Default

Jason, wire up two and send one to Dame to test with his Actron.
willwren is offline   Reply With Quote
Old 11-07-2004, 10:21 PM   #19
Senior Member
True Car Nut
 
Join Date: Nov 2002
Location: Texarkana, Texas
Posts: 6,041
Thanks: 0
Thanked 0 Times in 0 Posts
Damemorder is on a distinguished road
Default

Quote:
Originally Posted by willwren
Jason, wire up two and send one to Dame to test with his Actron.
I LOVE his ideas...
Damemorder is offline   Reply With Quote
Old 11-07-2004, 10:22 PM   #20
Junior Member
Posts like a Ricer Type-R
 
Join Date: Aug 2002
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road
Default

With your L27 and scantool, you're the best candidate to characterize this. Compare your findings with Jason'* seat-of-the-pants dyno.

Although you'll find that this time of year it won't make much difference.
willwren is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Electrical engineers needed for this issue... sandrock Everything Electrical & Electronic 0 02-07-2008 05:26 PM
Any Electrical Engineers? Laptop inquiries Drifter420 Lounge 20 09-07-2006 10:01 PM
I know some of you are engineers.... Damemorder Performance, Brainstorming & Tuning 12 06-21-2005 04:52 PM
Mechanical engineers and designers Spiral Lounge 13 01-06-2005 12:19 AM
Automotive Engineers Around? Old_School_Club Lounge 9 06-07-2004 11:23 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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 05:03 PM.


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.