Guess I'm officially old. This just seems overly complicated. If you want to heat it up quicker, why not, well leave the pump off and lean up the mixture? Kick the pump on when you have some temp in the water. Electric stat control for the fan isn't a bad idea and easy enough to do.

This is what I’ve seen with racers switching from gas to methanol carb in door cars.

The ones that do not downsize the radiator to better match the actual cooling needed for methanol end up trying all the different ways (thermostats, short filling cooling system, cardboard, lean out valves) to maintain engine heat. To me, they are doing it the hard way.

If the coolant system is properly sized using methanol you should be able to maintain a desired water temp (no thermostat) with the fuel mixture not using the fan or only cycling the fan very intermittently to maintain. And this should work in racing air temps from 50* to 100* imho.

Part of the reason I picked up so much when I first went to alcohol was because I went with a very small radiator and smaller hoses losing weight over front end.

I Like to run a thermostat even though most racers do not. I also run a primer system and if it was ever getting too hot I could hit the primer to help cool. Never had to do that but it is something in an emergency.
Keeping your engine temp under control is important and I prefer to use a thermostat to help. If you do not want to that is cool to.

Proper tuning with alcohol will help it get up to temperature faster, use less fuel and less milking of the oil.

I also use a thermostat on the fan but can still turn fan off manually. Like others here I lean it out and toggle water pump off to help get motor up to temp quicker.

quote:

Originally posted by TOP38:
I see absolutely no reason to run a thermostat in any race motor.

this^^^

nope no need for thermostats or drilling holes or magic wands . try paying attention to gauges and look at them on occasion it ain,t hard to do .

Tip
If your water pump is off you are not getting a accurate temperature reading on your gauge. If you wait until you see 130 or 140 degrees on the gauge before turning the water pump on you could be boiling the water around the exhaust valves in the heads.
This goes for gas or alky. When running your engine with the water pump off, turn the pump on for a few seconds to check temperature.

You would be surprised how often I have to tell people this over the phone.

quote:

Originally posted by 1leg:
Tip
If your water pump is off you are not getting a accurate temperature reading on your gauge. If you wait until you see 130 or 140 degrees on the gauge before turning the water pump on you could be boiling the water around the exhaust valves in the heads.
This goes for gas or alky. When running your engine with the water pump off, turn the pump on for a few seconds to check temperature.

You would be surprised how often I have to tell people this over the phone.

On some cooler days, I will cycle the pump on and off in like 30 seconds to 1 minute intervals to let the heat build up during warm ups.. Other than that, with a rather large radiator I can get the car to 150 with leanout fairly easy, and then the car will stay right at 160-165 with just water pump circulating through the radiator, and only touch the fan on warm days when I'm hot lapping the car.

I've been running 180 stats in both cars for 25 years. One 1/16 hole for air purge. -6 bypass hose from intake to pump suction, just like a street car. I want to circulate the block, not the radiator. No stat means you have to get ALL of the coolant up to temp. This seems illogical to me.
I always hear that your carb isn't right if you have it a little rich on the idle circuit. well every combo is different. I need a clean jump on the convertor every time. Cam, stall speed, intake volume can sometimes create a flat spot off idle that will cost you a round. My racepak shows a lean spike when stabbing it, so I fatten the idle a little to make the car work. I have 4 circuit carbs, and have fattened the midrange too.
There is no absolute answer, but I do believe that leaving the line at 180 makes a huge difference in consistency. If I leave at 170, I'll lose .05 every time.
If you don't vaporize the fuel, it won't burn.

RIP

Big investment of $5.99 in a thermostat seemed well worth the investment to try

quote:

Originally posted by SC4400:
I've been running 180 stats in both cars for 25 years. One 1/16 hole for air purge. -6 bypass hose from intake to pump suction, just like a street car. I want to circulate the block, not the radiator. No stat means you have to get ALL of the coolant up to temp. This seems illogical to me.
I always hear that your carb isn't right if you have it a little rich on the idle circuit. well every combo is different. I need a clean jump on the convertor every time. Cam, stall speed, intake volume can sometimes create a flat spot off idle that will cost you a round. My racepak shows a lean spike when stabbing it, so I fatten the idle a little to make the car work. I have 4 circuit carbs, and have fattened the midrange too.
There is no absolute answer, but I do believe that leaving the line at 180 makes a huge difference in consistency. If I leave at 170, I'll lose .05 every time.
If you don't vaporize the fuel, it won't burn.

RIP

Spot on!
I run a 180 degree t/stat on alcohol as well, don't have to run it as long to warm up, also run a lean out valve and carb tune up is nice and clean.
A thermostat only does 1 thing, maintains the minimum operating temp, it helps them warm up quicker, on some engines depending on how the bypass is setup they will overheat if removed.
And for what we do consistency is a big plus!
180 degrees coming in to stage for me also for the same reasons,
All positives
Cheers

Some good info to think about on this thread. And the best part is it hasn't gotten sidetracked or blown up. (Not yet, anyway).
Like Rip said, nothing about this is absolute. Where one might ask "Why would I?", another might ask "Why not?". No rule saying either way of thinking is the right or wrong or best approach. And so much of drag racing is like life itself, performing better on raceday, or at work, or at home, is generally a continuous learning experience. We should always be looking at every aspect possible to find little improvements in our program, be it consistency, quicker warmups or cooldowns, reduced maintenance requirements / improved reliability etc. Sometimes it doesn't hurt to rethink things that we might assume are "gospel", or that we've done because that is the way it has always been done, etc.
A good way to approach a different idea than what you are currently using, is to consider "How might this benefit my program"? And then look at the converse angle, of course - "What are the downsides, if any". A thermostat weighs a couple ounces, and costs a few dollars, and takes 5 minutes to easily remove or install, and are readily available everywhere. So none of these factors present any kind of obstacle to any of us.
For most of us, the chosen sport is some form of bracket or Index racing, (not Top Fuel, P/S or Comp). I spent decades using the tried and true old school no t-stat approach. I prefer to almost always have the water pump running, to avoid hot spots in the heads. With a door car and a large radiator, it took a long time to get the coolant up to temp in cool or even warm weather. When I switched to alcohol, it was worse, even in hot weather, (a leanout helped a lot though). I got to thinking along the lines Rip mentioned, I was having to heat the entire system volume of coolant. I went back to using a thermostat, which greatly improved (reduced) warmup time and associated fuel usage. I also included the bypass hose, to circulate coolant through the block & heads, even when stat is closed. I also experimented with different size and number of holes drilled in the outer flange of the stat. Tried 3, then 2, then 1 hole at 1/8" - 3 was about same as not using a t-stat, even 2 was too much flow. Eventually settled on one .060" hole (1/16th would be equivalent). This allows for bleeding air bubbles out, and for gradually heating the rest of the coolant, but still provides quick warmups, and also reduces the temperature swings you see between open/closed thermostat. Car has never been more consistent.
Not saying it is the best way or what anyone else should do but it works for me.

quote:

Originally posted by Bucky:
Guess I'm officially old. This just seems overly complicated. If you want to heat it up quicker, why not, well leave the pump off and lean up the mixture? Kick the pump on when you have some temp in the water. Electric stat control for the fan isn't a bad idea and easy enough to do.

Leaving the water pump off *can* cause hot spots, and even localized boiling. (notice I said "can").

With that said, there was 2 times of year that I ran a thermostat. Obviously when racing in cold weather. Also when I was racing and it was REALLY hot. During hot weather I'd richen the idle mixture to make it easier to keep cool, but used a thermostat so it's not ever too cold(call me lazy lol). If it's above 55, but below 90 I'd run without a thermostat.

My 2 cents,

I run alky, electic water pump, thermostat and aluminum radiator.

One thing that really hasnt been hit on directly is cooling capacity. Consider this, when you dont have a thermostat, you have to heat the entire cooling system to get the engine up to temp. My opinion, alot of wasted fuel and idle time.

Now consider when you run a thermostat, you are heating the coolant in the engine before you are tapping into your reserve coolant in the radiator. In other words you have more reserved cooling capacity to maintain a more consistant coolant temp in the engine. Engine may be 180 degrees, but with a thermostat, coolant in the radiator may only be 160. Where without a thermostat, everything is at 180 and you are closer to overwhelming your coolant system.

My philospy, set my stuff up for the more extreme situations. I am pretty much always double entered, and live in texas, so most race days during the summer are 95+. I typically make a pass 180-190. Its pretty easy to maintain because of the tempature differential. I watch guys that like to run cooler struggle to cool there stuff. Its alot easier to maintain 185 temps with 95 degree ambient air than it is to cool it to 120 degrees. No problem making multipy back to back passes getting down to the later rounds.

Am i leaving et on the table, probably, but we are bracket racing where consistancy and repeatabilty is king. No bonus points for running as fast as you can.

I am for automating tempature control as much as possible. I do keep my eye on the gauges, but the thermostat makes it eaiser to maintain.

I also run a oil thermostat in my transmission. Really easy to build and maintain temp in transmission, plus tons of cooling capacity when i need it. One of the best things I have done for consistancy for footbraking.

Speaking of cooling capacity, maybe that's why mine has always been easy to manage. On my small block, alky car, I use all -8 lines. No issues with getting hot ever. Maybe it is restrictive enough though that no thermostat or restrictions are needed.
I was shocked when a car I bought for my son had -16 lines to the radiator. Not sure we need that large for a small LS bracket engine. But I don't guess it will hurt either.

My car uses a factory replacement radiator and standard radiator hoses. It's worked well on gas like that for 20 years and I probably will have it back on gas possibly when it gets to be Oct. or Nov. Not going to change my cooling system if a thermostat will make it work.

For those of you talking about running your motors at 180 degrees on alcohol for consistency or to help horsepower.... Have any of you tried this on a dyno? I have. It don't work. anything north of 130 degrees is worthless and actually made less power on the dyno. Of course the dyno thermostat opened at 165 and i couldnt' get it any higher but my MFI, 565, 14.5: compression, BBC, on methanol didn't like it. That was after we made 25+ pulls getting timing, fuel, valve lash, high speed, etc where we wanted it then just for kicks and grins we made a few pulls at progressively higher and higher water temperatures till we couldn't get it any hotter because of the thermostat. In each case above 130 degrees the motor either made exactly the same HP or less (very minor differences) but still less.

I just can't understand why anyone thinks they need to stage a racecar at 180 degrees, just doesn't make sense to me.

No need to explain, i know many of you do it and believe in this practice and have won thousands of races like this i'm sure many more than i have, but in my experience its a waste of time. I've seen it on the dyno and backed that up on the racetrack several times with back to back runs at different temperatures. Higher water temps for me yield slower ET. This is racing at racetracks at or very close to sea level elevation and in air ranging from -400 DA to +2500 DA.

The current ride is a dragster so keeping temps aat or below 130 is a non issue even double entered.. If thats a problem ricchen the idle and keep the fans and water pump running all the time. If you need to warm it up, cycle the water pump on and off while keeping the fans off till the temp comes up. How hard is that?????? Previous rides were door cars with same motor or very similar (77 gremlin and 72 Nova) nova was all steel, gremlin was a chassis car. Neither had big massive radiators neither had problems keeping cool in 100+ weather, both were double entered on occasions.

All of my cars slow down when the OIL TEMP is too low, but water temp at 130 is just perfect for me.

G,day,
I've done it several times with mine on the engine dyno, on petrol it liked being cold.
On methanol the more temp we put in it the more it made consistantly.
I pulled it up at 180, that's where i stage, will be higher at the end of the pass.
The warm up advantages have already been mentioned several times on this thread
i have a large cooling system with a 180 t/stat i can turn the car around quickly in the later rounds and no problems keeping the temp consistant.
The engines i'm into on methanol all see the same thing, they are cast iron headed, may play a part?
There are no disadvantages to running a t/stat whatsoever
it does 1 thing only - it controls the minimum operating temp, that's it.
And it has a lot of advantages,
Cheers

Triple Nickel, That is interesting. I have been running alcohol since 1998 and my cars runs faster at warmer water temperatures. My thinking there is if the car is faster it is more efficient and probably more consistent to.

I try to do everything the same and have not tested it in a while.
Maybe I should do some testing again to verify?

Don't know if I'm any help, but with my modest gas motor I removed the core from a thermostat, use a stock water pump with a 100-dollar electric pump drive, and two 14-inch high-volume fans.

I'll start the engine and flip the switch for the water pump drive.
When the engine approaches 160 degrees I turn on one fan. When it reaches 160 degrees I flip on the 2nd fan and it pretty well stays at that temp until I launch.