Kill No Cone

iTrader: (6)

Have any of you guys drilled some holes in the outer edge of your thermostat so there is always some water flowing?

RETed

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

RX744CSP

iTrader: (4)

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).

CrispyRX7

iTrader: (139)

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?

Dick Elliott

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.

RETed

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

Kill No Cone

iTrader: (6)

Thanks guys this has been very helpful.

CrispyRX7

iTrader: (139)

Thanks Ted. Why is the image code turned off?
Oh well
Crispy

DamonB

Dunno. Ask an Admin.

clayne

They're never around.

DamonB

Nice to hear it's not just us Mods that they ignore

RETed

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

DamonB

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.

CrispyRX7

iTrader: (139)

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

DamonB

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

CrispyRX7

iTrader: (139)

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?

DamonB

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.

Kill No Cone

iTrader: (6)

Well, after drilling some holes it was sure nice to fill with coolent. Quick and easy now that the air bleeds out.

chairchild

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