can water injection help heat soak issues? - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Methanol/Water Injection Place to talk about meth/water injection.

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 07-11-2012, 02:15 PM   #1
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Oregon
Posts: 278
Total Cats: 7
Default can water injection help heat soak issues?

After searching/reading up on WI; I don't believe that WI can be used to solve my heat soak problems; please correct me my thinking is wrong:

My problem seems to stem from track operation past approx 15 mins; my intake air temps begin rising to the point that the ECU stats pulling timing, then the engine is power is reduced for the last half of the race.

While there is no question in my mind that WI will reduce detonation and make the engine run cooler, it wouldn't seem to help out my problem of heat soak causing high IAT readings, as the WI is not injecting into the heated air stream that the IAT sensor is reading. Further, it doesn;t seem that cooling the engine would have any effect on heat soak of the intake stream, as this is mostly a function of heating from the compression of the intake air; independent of heating of the engine.

As the threads I've encountered all say that you need to inject the water/meth right into the throttle body, this seems to do nothing to lower the temps of my IAT sensor; which is upstream from the throttle body.

When I began to look into injecting further upstream (with the hopes of cooling the intake stream prior to the IAT sensor) it seems that no one was doing that. I suppose it either didn't work, cooled the sensor too severely, water came out of suspension/pooled in the inter-cooler, or some other such problem.

If WI will not help, then what other solutions do all of you use to cure heat soak? I've got a large barr/plate intercooler, placed and ducted into clean air.

Last edited by gtred; 07-11-2012 at 02:39 PM.
gtred is offline   Reply With Quote
Old 07-11-2012, 02:37 PM   #2
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,872
Total Cats: 1,790
Default

what sort of AITs are you seeing? where is your AIT sensor exactly? you do have a FMIC?
Braineack is offline   Reply With Quote
Old 07-11-2012, 04:41 PM   #3
Elite Member
iTrader: (2)
 
Join Date: Jan 2007
Location: Los Angeles, CA
Posts: 8,782
Total Cats: 119
Default

No. Your ducting is broken.

If ur IC is the right size it should work.

Water injection is best when u have a seperate fuel and timing trim for when it is spraying. And a failsafe when not.

If you spray water on top of the tune you have now without trims or retuning, you will lose power.

Myself. I would not use WI on track. Another thing to go wrong. Just pay the price for some race gas and you should be safe from det.

You still need to redo ur ductig thoough.

And. How are u sure your IATs are climbing? Your AITs have to rise a LOT to pull say 3*.
Faeflora is offline   Reply With Quote
Old 07-11-2012, 04:43 PM   #4
Elite Member
iTrader: (2)
 
Join Date: Jan 2007
Location: Los Angeles, CA
Posts: 8,782
Total Cats: 119
Default

Oh and what brain is gettin at:

Expose your AIT sensor bulb to the airstream. Sometimes they sit in a crappy little metal weld on sleeve that gets hot and messes up readings.
Faeflora is offline   Reply With Quote
Old 07-11-2012, 04:50 PM   #5
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,872
Total Cats: 1,790
Default

well I've never had that issue, so I'm surpirsed it's heat soaking during driving, on the trakc or not. I need more deets.
Braineack is offline   Reply With Quote
Old 07-11-2012, 05:27 PM   #6
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Oregon
Posts: 278
Total Cats: 7
Default

In all fairness, I am just assuming that it is heat soak. The symptoms are that I am down on power after 15 mins of track time and the cars I used to hang with are pulling me on the straights.

Next event is at the end of the month and I'll come prepared with an air intake temp gauge.

Here's a pic of my intercooler. The ducting seals up the nose pretty well.

I did relocate the IAT sensor into a steel inlet pipe with a steel threaded sleeve, from the OEM rubber inlet elbow. Good point that the underhood heat might be heating the steel tubing/sleeve which might be effecting the temps that the sensor is seeing. I see that some of you have moved your IAT sensor to the cold side pipe of the inter-cooler; perhaps for this reason? I'll look into this.

Thanks for your quick responses.

Last edited by gtred; 05-01-2017 at 11:48 AM.
gtred is offline   Reply With Quote
Old 07-11-2012, 06:08 PM   #7
mkturbo.com
iTrader: (24)
 
shuiend's Avatar
 
Join Date: May 2006
Location: Charleston SC
Posts: 13,776
Total Cats: 1,106
Default

Move your IAT to the coldside of the intercooler right after the exit. You do not want it up in the engine compartment.
shuiend is online now   Reply With Quote
Old 07-11-2012, 06:09 PM   #8
Elite Member
iTrader: (10)
 
soviet's Avatar
 
Join Date: Jan 2010
Location: VA
Posts: 3,518
Total Cats: 258
Default

wait.
what?

We have AIT sensor on cold side because THAT'S THE AIR THAT'S GOING INTO THE ENGINE. Because that's how the ECU works, ideally, you want MAP and AIT sensors at the exact same location but that doesn't always work out for other reasons.

I can only assume that air temp on hot side is something retarded like 300F....
soviet is offline   Reply With Quote
Old 07-11-2012, 06:40 PM   #9
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Oregon
Posts: 278
Total Cats: 7
Default

Quote:
Originally Posted by soviet View Post
wait.
what?

We have AIT sensor on cold side because THAT'S THE AIR THAT'S GOING INTO THE ENGINE. Because that's how the ECU works, ideally, you want MAP and AIT sensors at the exact same location but that doesn't always work out for other reasons.

I can only assume that air temp on hot side is something retarded like 300F....
The factory location for the intake air temp sensor was on the cold side, but right up at the elbow that feeds the throttle body. On the forum's recommendation I'm going to relocate this to the cold side outlet of the inter-cooler.

Other Forum threads have elluded to the 120-130+ degree mark as to when the ECU starts pulling timing. Are you in general agreement with this range? Do you have an opinion as to how hot is too hot for an intake air temp?
gtred is offline   Reply With Quote
Old 07-11-2012, 06:46 PM   #10
Elite Member
iTrader: (2)
 
Join Date: Jan 2007
Location: Los Angeles, CA
Posts: 8,782
Total Cats: 119
Default

no logging??? what is the point of having a damn ems?????
bleh
Faeflora is offline   Reply With Quote
Old 07-11-2012, 06:47 PM   #11
Elite Member
iTrader: (2)
 
Join Date: Jan 2007
Location: Los Angeles, CA
Posts: 8,782
Total Cats: 119
Default

Quote:
Originally Posted by gtred View Post
Other Forum threads have elluded to the 120-130+ degree mark as to when the ECU starts pulling timing. Are you in general agreement with this range? Do you have an opinion as to how hot is too hot for an intake air temp?

There is no agreement. It is a fixed table in the EMS.

Actually. What is your EMS?

Also it pulls like 1 crappy degree at 120*.
Faeflora is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Expected intake temps on the track? tazswing Race Prep 20 10-03-2015 12:04 PM
Time to start learning and play with tuning The Gleas MEGAsquirt 3 10-01-2015 10:30 AM
Leaky Wilwoods mx592 Suspension, Brakes, Drivetrain 1 10-01-2015 01:45 AM
Bad head gasket or ? shooterschmidty Engine Performance 8 09-30-2015 11:28 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 07:02 PM.