Go Back   986 Forum - for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Performance and Technical chat

Reply
 
LinkBack Thread Tools Display Modes
Old 09-15-2014, 02:11 AM   #1
Rennzenn
 
j.fro's Avatar
 
Join Date: Feb 2005
Location: Virginia
Posts: 1,355
Garage
Thermostat question

Ok, so we know that excessive heat/ poor cooling can be an issue with the m96 engine. There also seems to be consensus for the 160 t-stat over the factory 180. A trick we used to use with Chevy drag car engines was to remove the spring and plug from a t-stat, creating a restrictor plate. Running without a t-stat wasn't so effective because the coolant moved too quickly through the engine to accumulate heat, but with the plate, it did the job and the engine stayed cool. How about this for the M96? I know the heater won't be very warm afterwards, but for a racer, I don't really care about that. Thoughts??
__________________
Rennzenn
Jfro@rennzenn.com
j.fro is offline   Reply With Quote
Old 09-15-2014, 03:49 AM   #2
still plays with cars...
 
BoxsterSteve's Avatar
 
Join Date: May 2011
Location: Baden, ON, Canada
Posts: 1,069
Garage
One issue that you may see would be oil change interval. If the coolant and consequently the oil never warm up enough, how often do you change oil because you're not burning off moisture and fuel that accumulate in the oil?
__________________
Six speed 2000 Boxster S
Arctic Silver on Metropol Blue | Arctic Silver console, spoiler frame & bumperettes | Crios mod | Technobrace | RoboTop module & modified convertible top relay for one-touch roof operation
BoxsterSteve is offline   Reply With Quote
Old 09-15-2014, 05:49 AM   #3
Registered User
 
jb92563's Avatar
 
Join Date: Apr 2012
Location: Riverside, CA
Posts: 1,663
Why use a restrictor when you can simply install a "variable restrictor" ie 160F T-Stat that will try to match the temp to optimum all the time.

Not sure I see any benefit to a restrictor as it only allows one fixed flow rate regardless of coolant temp.

Really whats needed is an electronic ECU controlled T-Stat.
__________________
"It broke because it wants to be Upgraded "
2012 Porsche Performance Driving School - SanDiego region
2001 Boxster S, Top Speed muffler, (Fred's) Mini Morimotto Projectors, Tarret UDP,
Short Shifter, Touch Screen Dual Din Radio, 03 4 Bow glass Top (DD & Auto-X since May 17,2012)
jb92563 is offline   Reply With Quote
Old 09-15-2014, 07:18 AM   #4
Certified Boxster Addict
 
Join Date: Nov 2010
Location: Los Angeles
Posts: 7,393
Engines have a preferred operating temperature and the goal is to keep the engine at that temp at all times, under all conditions. Running the engine hotter or cooler than the preferred temp hould be minimized and/or avoided if possible.

In a perfect world, what we'd really like is an engine heater to warm the engine and oil to operating temp prior to even starting the car! Then we'd like a thermostat to maintain that optimal operating temp throughout all ranges of use and external temperature extremes. This could be accomplished by having infinite cooling capacity at all external temp extremes.

Problem solved!

Running the car without a t-stat will delay getting the engine up to operating temp. On cool days, the engine might not ever get to operating temp because the cooling system (radiators) are always in the loop.

Thus, the low temp t-stat is an easy and cheap way to get the engine up to the preferred operating temp and keeping it there without modifying the cooling system and spending $$$ to do so.

To carry this discussion on to the next logical step; the next move towards that perfect system would be to increase cooling capacity by installing the Boxster S model center radiator into the base cars or install more efficient raditors.

Our Forum owner has provided a convenient DIY that shows how to install the Boxster S center radiator. The parts kit new is $1,100 but you can often find a used S radiator and piece together the hoses and other parts for much less: Boxster Center Radiator Installation.

More efficient radiators for the Boxster base cars can be found here (among other places): Porsche Aluminum Radiators
__________________
1999 996 C2 - sold - bought back - sold for more
1997 Spec Boxster BSR #254
1979 911 SC
POC Licensed DE/TT Instructor

Last edited by thstone; 09-15-2014 at 07:33 PM.
thstone is offline   Reply With Quote
Old 09-16-2014, 08:13 PM   #5
Registered User
 
jb92563's Avatar
 
Join Date: Apr 2012
Location: Riverside, CA
Posts: 1,663
With all the electronics these days I cant imagine why the coolant system is not ECU controlled to maintain the perfect operating temperature.

Perhaps the benefit does warrant the extra effort to add the necessary components?
__________________
"It broke because it wants to be Upgraded "
2012 Porsche Performance Driving School - SanDiego region
2001 Boxster S, Top Speed muffler, (Fred's) Mini Morimotto Projectors, Tarret UDP,
Short Shifter, Touch Screen Dual Din Radio, 03 4 Bow glass Top (DD & Auto-X since May 17,2012)
jb92563 is offline   Reply With Quote
Old 09-17-2014, 03:27 AM   #6
Registered User
 
Join Date: Aug 2010
Location: Florida
Posts: 156
Once the thermostat is open operating temperature is ECU controlled by the fans. With thermostat open it is the air across the radiators that help to regulate operating temperature.
opus69 is offline   Reply With Quote
Old 09-17-2014, 12:41 PM   #7
Registered User
 
Join Date: Feb 2005
Location: It's a kind of magic.....
Posts: 5,079
Quote:
Originally Posted by jb92563 View Post
With all the electronics these days I cant imagine why the coolant system is not ECU controlled to maintain the perfect operating temperature.

Perhaps the benefit does warrant the extra effort to add the necessary components?
Buy a new Boxster and you will get your wish; they call it a "thermal management system".
__________________
Anything really new is invented only in one’s youth. Later, one becomes more experienced, more famous – and more stupid.” - Albert Einstein
JFP in PA is offline   Reply With Quote
Old 09-17-2014, 02:34 PM   #8
Registered User
 
epapp's Avatar
 
Join Date: Aug 2013
Location: Bay Area
Posts: 700
Garage
Any idea how the 'cooling policy' works in this system? They don't talk much about it on the website. Do they have an adjustable thermostat or is it something simple like a more aggressive fan control?
epapp is offline   Reply With Quote
Old 09-18-2014, 01:07 PM   #9
Registered User
 
Join Date: Feb 2005
Location: It's a kind of magic.....
Posts: 5,079
Quote:
Originally Posted by epapp View Post
Any idea how the 'cooling policy' works in this system? They don't talk much about it on the website. Do they have an adjustable thermostat or is it something simple like a more aggressive fan control?
I have not seen one apart yet, but it has to be more complicated as it runs the car super hot (225F+) until you open the throttle wide, when it quickly drops the coolant to around 180F for the duration of the WOT power, then jumps back up over 225F when the thottle closes.

Got to be bypass valves and such involved to pull that kind of temp drop that quickly.
__________________
Anything really new is invented only in one’s youth. Later, one becomes more experienced, more famous – and more stupid.” - Albert Einstein
JFP in PA is offline   Reply With Quote
Old 09-18-2014, 01:33 PM   #10
Registered User
 
epapp's Avatar
 
Join Date: Aug 2013
Location: Bay Area
Posts: 700
Garage
I guess it isnt SO bad that our high speed fans come on at 217 then??

..here I am designing my own fan controller based on driving conditions..
epapp is offline   Reply With Quote
Old 09-18-2014, 01:51 PM   #11
Registered User
 
Join Date: Sep 2014
Location: Turkey
Posts: 3
I have 996 3.4 carrera m96 engine has warm problem but problem solve is basic. I live in istanbul and istanbul warm city it has traffic jam also water temperature up to 100c sometimes 105c. Radiator fans have a 3 Level first Level on 96c second Leve on 103c its late for engine but you try open ac radiator fan open level 3 so water temperature must under the 96c. I perefer you buy 73c termostat Arabic countries or warm countries use it. And in the traffic you must open ac.


Sent from my iPhone using Tapatalk
gurkanbo is offline   Reply With Quote
Reply


Thread Tools
Display Modes

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 On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 04:15 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page