Race Car Tech Discuss anything related to road racing and auto X.

Holes in the thermostat?

Thread Tools
 
Search this Thread
 
Old 04-27-04 | 02:38 AM
  #1  
Kill No Cone's Avatar
Thread Starter
Rotary Freak
iTrader: (6)
 
Joined: May 2002
Posts: 1,989
Likes: 1
From: Olympia WA
Holes in the thermostat?

Have any of you guys drilled some holes in the outer edge of your thermostat so there is always some water flowing?
Old 04-27-04 | 04:33 AM
  #2  
RETed's Avatar
Lives on the Forum
 
Joined: Feb 2001
Posts: 26,664
Likes: 19
From: n
Stock Mazda OEM thermostats already have a single jiggle pin.
Else, there is a 1/2" bypass hole already in the water pump housing.

-Ted
Old 04-27-04 | 10:05 AM
  #3  
RX744CSP's Avatar
Senior Member
iTrader: (4)
 
Joined: Apr 2004
Posts: 340
Likes: 0
From: Charleston, SC
OE thermostats have a jiggle pin, some aftermarkets do not. I drilled a 7/64 hole in mine, before I did that it was possible to intermittently have an air pocket trapped behind the thermostat which would do two things: the thermostat wouldn't open at the correct time, and occasionally the temp gauge wouldn't work (I use a mechanical gauge with the bulb installed in the housing where the choke thermo switch used to be). If there's no coolant contacting the bulb, the gauge reads zero (not good).
Old 04-27-04 | 12:26 PM
  #4  
CrispyRX7's Avatar
Polishing Fiend
iTrader: (139)
 
Joined: Apr 2001
Posts: 3,393
Likes: 43
From: MD
Like this maybe?
http://www.negative-camber.org/crisp...illedtstat.jpg

In answer to your question then it would be yes I do (but only in the summer when my car is seeing mostly track duty)
HTH,
Crispy

[IMG]http://www.negative-camber.org/crisp...illedtstat.jpg[/IMG]

Edit: for some reason I can't get the image to show up here?

Last edited by CrispyRX7; 04-27-04 at 12:33 PM.
Old 04-27-04 | 01:02 PM
  #5  
Dick Elliott's Avatar
Senior Member
 
Joined: Jan 2003
Posts: 552
Likes: 0
From: Springdale,AR
I drill a small hole to one side of the stat to allow the air to bleed off when you fill the system. .040 dia hole is all you need. After you reach .060 dia you will start makeing the stat work at a lower temp. It is possible to make a 180 deg stat into a 160 deg one by drilling a .060 dia hole. This works good for an autocross car but a road racer will reach 180 deg just the same sooner or later. All stats should have this hole but the bean counters say no I guess. Saves a penny a zillion don't you know.
Old 04-27-04 | 01:22 PM
  #6  
RETed's Avatar
Lives on the Forum
 
Joined: Feb 2001
Posts: 26,664
Likes: 19
From: n
Originally posted by CrispyRX7
Edit: for some reason I can't get the image to show up here?
Look in the bottom left corner of this page - [IMG] code is OFF so no one can post pics in this particular forum section.


-Ted
Old 04-28-04 | 01:42 AM
  #7  
Kill No Cone's Avatar
Thread Starter
Rotary Freak
iTrader: (6)
 
Joined: May 2002
Posts: 1,989
Likes: 1
From: Olympia WA
Thanks guys this has been very helpful.
Old 04-29-04 | 03:17 PM
  #8  
CrispyRX7's Avatar
Polishing Fiend
iTrader: (139)
 
Joined: Apr 2001
Posts: 3,393
Likes: 43
From: MD
Thanks Ted. Why is the image code turned off?
Oh well
Crispy
Old 04-29-04 | 03:22 PM
  #9  
DamonB's Avatar
Lives on the Forum
 
Joined: Feb 2001
Posts: 9,617
Likes: 8
From: Dallas
Originally posted by CrispyRX7
Thanks Ted. Why is the image code turned off?
Oh well
Crispy
Dunno. Ask an Admin.
Old 04-29-04 | 04:42 PM
  #10  
clayne's Avatar
PV = nRT

 
Joined: Jan 2003
Posts: 2,250
Likes: 0
From: New Zealand (was California)
They're never around.
Old 04-29-04 | 04:49 PM
  #11  
DamonB's Avatar
Lives on the Forum
 
Joined: Feb 2001
Posts: 9,617
Likes: 8
From: Dallas
Originally posted by clayne
They're never around.
Nice to hear it's not just us Mods that they ignore
Old 04-29-04 | 05:08 PM
  #12  
RETed's Avatar
Lives on the Forum
 
Joined: Feb 2001
Posts: 26,664
Likes: 19
From: n
Originally posted by CrispyRX7
Thanks Ted. Why is the image code turned off?
Oh well
Yeah, I have no idea why it's like that either.
I'm not a mod nor an admin, so I can't do anything about it.

-Ted
Old 04-29-04 | 05:32 PM
  #13  
DamonB's Avatar
Lives on the Forum
 
Joined: Feb 2001
Posts: 9,617
Likes: 8
From: Dallas
Originally posted by CrispyRX7
In answer to your question then it would be yes I do (but only in the summer when my car is seeing mostly track duty)
HTH,
Crispy
Crispy, any idea how much difference you see in hot weather with the "holy" thermostat?

I'm waiting for the 100 degree summer to test my front splitter more but the thermostat is something I've been thinking to do.
Old 04-30-04 | 10:39 AM
  #14  
CrispyRX7's Avatar
Polishing Fiend
iTrader: (139)
 
Joined: Apr 2001
Posts: 3,393
Likes: 43
From: MD
Damon,
Hard to say. What we are talking about is margin of safety. In all my days tracking my car I've never overheated it. But I find the faster and harder I drive, there also comes commensurate additional modifications to keep temperatures in check. Things like the "holy" t-stat. There is no question in my mind that it does help with coolant flow and thus more "efficient" cooling but I am not of a mind to try running my car without it in 90degree weather at 12psi and see if the car runs hotter
What I can say though is that in cold weather when I've been caught with it installed (a frosty morning) where my car will normally run with an undrilled tstat at a thermstatically controlled 195degF (90degC) or whatever it is, the car will NEVER get up to operating temperature. Driving to the track (Summit Point) one morning in last year in ambient temps around 30deg F the engine temps never exceeded about 55degC on the PFC. This meant coolant was being *overcooled* by my superefficient cooling system. The car simply did not generate enough heat. And let me tell you it was a cold ride that morning. No heat in the coolant also means no heated air for the driver either!
FWIW
Crispy
Old 04-30-04 | 01:11 PM
  #15  
DamonB's Avatar
Lives on the Forum
 
Joined: Feb 2001
Posts: 9,617
Likes: 8
From: Dallas
Originally posted by CrispyRX7

What I can say though is that in cold weather when I've been caught with it installed (a frosty morning) where my car will normally run with an undrilled tstat at a thermstatically controlled 195degF (90degC) or whatever it is, the car will NEVER get up to operating temperature.
Sounds like I need to do it then First I went to 80% water/20% coolant; that helped quite a bit. Then I made baffles blocking off the sides of the inlet to the stock radiator; that helped quite a bit. Then I made the splitter; that seems (haven't tested it enough yet) to have helped quite a bit. Holy thermostat could be the icing on the cake

If I had to guess I bet my present combo with the splitter is good to about 90 degrees outside. I need 100+ for these Texas summers at the track if I don't want to have to slow down
Old 04-30-04 | 01:20 PM
  #16  
CrispyRX7's Avatar
Polishing Fiend
iTrader: (139)
 
Joined: Apr 2001
Posts: 3,393
Likes: 43
From: MD
Damon,
In case you haven't read it elsewhere I typically see about 105degC on the track in pretty much any ambient temp above 80degF running a solid 12psi boost. And I've done IMO have almost everything one can do to get temps down including all those you noted. I've seen pics of your splitter and it should help also. The drilled tstat will help
Regards,
Crispy

PS you use water wetter?
Old 04-30-04 | 02:57 PM
  #17  
DamonB's Avatar
Lives on the Forum
 
Joined: Feb 2001
Posts: 9,617
Likes: 8
From: Dallas
Originally posted by CrispyRX7
PS you use water wetter?
Have not tried it. I fully believe it's just a wives tail that it is harmful to the coolant seals but my goal has been to see what I can do without it.

The coolant system has a definite threshold and as long as you stay below that temps are fine. No matter what the coolant mods my experience with my car has shown a few degrees difference in outside temp or a couple hundred difference in RPM can make big changes in coolant temp. When temps begin to rise too high or too quickly I first begin shifting about 200 rpm sooner. If that shows improvement but not enough I'll shift 500 rpm sooner and so on. Usually I don't have to make a concious effort to drive "slow" even though short shifting is in effect doing that.

I still plan to try underdriving the water pump only for the track. I spend all my time at 5500+ rpm and I've always wondered if the big difference in coolant temp due to slight decreases in RPM are more due to the fact the water pump cavitates at high rpm rather than actual heat...

I should have definitive answers on the splitter and the water pump pulley this summer.
Old 05-03-04 | 12:47 AM
  #18  
Kill No Cone's Avatar
Thread Starter
Rotary Freak
iTrader: (6)
 
Joined: May 2002
Posts: 1,989
Likes: 1
From: Olympia WA
Well, after drilling some holes it was sure nice to fill with coolent. Quick and easy now that the air bleeds out.
Old 05-08-04 | 08:25 PM
  #19  
chairchild's Avatar
50mpg - oooooh yeah!

 
Joined: Mar 2003
Posts: 527
Likes: 0
From: UK
ever thought about using an electroninc T/s?

It'd make the job a whole lot easier for you, because instead of having to:
drain the coolant,
undo some bolts,
remove the T/s,
put a different one in,
put the bolts back in,
refill the coolant,
then bleed the air off

...all you'd have to do, is twiddle with a small dial on the dashboard
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
djessence
1st Generation Specific (1979-1985)
1
10-04-15 11:21 AM
pfsantos
2nd Generation Specific (1986-1992)
1
09-30-15 02:29 PM
MidnightOwl
2nd Generation Specific (1986-1992)
1
09-25-15 11:24 PM




All times are GMT -5. The time now is 01:25 AM.