Track Operating Temperature - Toyota Nation Forum : Toyota Car and Truck Forums

anarkia1ces · 07-21-2005, 01:23 AM

For track, I have done a bypass of the heater hose of my engine (Stock internals) to raise the operating temperature. I disconnected the hoses to the heater pipes, and joined them with a single hose straight from the thermostat housing to the engine head. This gives you about 20C more.. which will appear in the temp gauge as two notches above middle. This is good to protect the engine in these conditions, in where I like to keep it between 4.8 and 7.2KRPMs. Peak torque in the mk1 is at about 6.6. I use mobil 1 as well. At these temperatures the engine internals will suffer from less wear and the motor itself performs smoothly throught the RPM range. Any comments on this? Can anyone relate? Thanks.

white90dx · 07-21-2005, 03:32 AM

Why would you EVER specifically try to raise the operating temperature of your motor on a racetrack? I have never heard of a car that doesn't use most if not all of its cooling ability on a racetrack. If your temp gauge goes much above the middle (on a stock gauge), your motor is getting to a point where it can be seriously damaged.

Where did you get this info?

-Charlie

terrastrife · 07-21-2005, 05:11 AM

most cars with stock cooling will in general run out of cooling capacity in 5-10 minutes (Water way way abouve 100c and oil way abouve 150, even if all ya standard gauges dont show anything high) on a track full throttle, maybe you arent driving fast enough?

anarkia1ces · 07-21-2005, 12:14 PM

Most track I go have only 1 straight away. My goal is optimum handling and not speed around the circuit. Anyone can push the pedal and go fast. I noticed that the temp (Even with a external gauge stays at 85C) does not go past the middle. I do ocasionally drift around corners (RPMs at that piont are between 7 and redline). Abusing the engine at low temps is a bad idea, specially on winter.

Also, I use water + wetter. I did all this on my own. The 2's colling system as you know has more piping than a regular car. If the timing is set right (Not severly advanced) the system will do its job well in maintaining normal temp, specially with coolant running on the 2 stainless steel pipes that run back and forth, further cooling the water (Metal transfers temp more than a rubber hose) and with no forward and rear fuel protectors they get air. Again this is just an experiment, and don't worry I am not harming my engine

. I think it's best for the temp to stay 3/4 (Maybe even have a notch below that point) above during the course for better response and less fatige to the rods and crank.

white90dx · 07-21-2005, 05:20 PM

I still fail to see how having a hotter motor is better? I know that it needs a minimum temp to work right (optimum combustion temperature, correct oil viscosity, correct clearances), but anything over that and you are loosing out on power. Anything over the normal operating temperature, you risk running oil that is too thin, and you may tighten up your clearances to the point of causing problems.

If your motor runs correctly the way you have it, more power to you. I just worry that other people (with cars that run more normally) could hurt their motor using this technique.

-Charlie

anarkia1ces · 07-21-2005, 05:42 PM

I agree with your comments. I do not recommend anyone to do this with an engine other than the 4AG as I have not tried this on any other car. I will note that if proceeding with lack of caution you can easily fry your engine (Blown headgasket, ruptured coolant hoses and engine failure in the worst cases), but then again, this is the Hardcore competition ONLY forum... right?

Use at your own risk. I feel the motor less sluggish with the temperature increase. As long as you have a good cold air intake you will not loose power. I also conducted this experiment to then analyse the bearings compared to a normally driven 4AG when I take it apart next year sometime.

anarkia1ces · 07-21-2005, 05:45 PM

Forgot to mention:

This is a similar technique used on liquid cooled go-karts. The difference is that they usually cover half of the radiator with tape to increase water temp.

***Eye8Pussies*** · 07-21-2005, 05:46 PM

^ werd

people add oil coolers and run 15w50 synthetic for a very good reason
maybe on a smaller car like an mr2, the engine doesn't run as hard to get the car around the track? on the cam (1mz), any tracking will need every bit of cooling the system can give

SmokingTires · 07-21-2005, 06:08 PM

Rasing the temp of the engine won't increase your performance in anyway unless you are in very low temps. Race car drivers bypass their thermostat all the time, but they do it to BETTER COOL THE ENGINE!

Your engines optimum operating temp is when it is full warm and the cooling system is funning at full. This would be directly in the middle. This is the best operating temp for your specific engine as it is designed. Going either way temp.-wise would decrease the engines ability to perform. Going cooler causes it to not have the performance it could have. Going warmer causes increased heat and friction to the engine. Although it is not visibly noticable at the time, it is increase the speed at which your engine wears.

The goal in racing is to keep your car cooler. Normal driving is enough to cause your engine to run at optimum temp. Racing and pushing your car harder causes it to increase temp (although you don't notice it while your racing because rightfully, your looking ahead and not at your gauges).
A good example would be the uses of your engine fan. My fan will usually not turn on during the summer, even after highway driving. However by the second half of an auto-cross, my fan was running at max capacity. And it ran that way for 5 minutes afterwards.

You want to cool your engine, not increase the temp...

Oh, and a cold air intake won't save your engine from being overheated. All it will do is let a small amount of colder air into the engine, which will be at 300degrees in just a second. So that really makes no difference at all.

anarkia1ces · 07-22-2005, 12:41 AM

Some of your comments are entirely true. But:
Ever owned/autocrossed/overhauled a MR2 MK1?

Or at least a mid-engine car?

SmokingTires · 07-22-2005, 05:30 PM

Quote:

Originally Posted by anarkia1ces

Some of your comments are entirely true. But:
Ever owned/autocrossed/overhauled a MR2 MK1?

Or at least a mid-engine car?

How does where the engine sit have anything to do with the way it runs? It doesn't!

I have rebuilt many engines, including a 7.0L Turbo Diesel. And I know that what you said is entirely untrue. Otherwise more cars would be do it. But they don't. Race cars are built with bypassed cooling systems that keep the engine cooler, not hotter.

It doesn't matter what engine in you have, or where it is placed, engine dynamics are still the same. The more you increase the temp over optimum operating temp, the more wear is increased. Optimuim

And to answer your question, yes, I have raced mid-engine cars. I'm running an NSX next week

anarkia1ces · 07-22-2005, 05:45 PM

Thanks for your comments. I will resume what I did and how my car runs

My engine is stock (No bigger cams, etc)
With the mod I did, the temp gauge stays 3/4 at all times, even when running sustained high RPMs.
I never ever said that the car is a race car or has a race engine. Just stock
I'm running 70% water 20% coolant 10% wetter
This is an experiment, only. Just wanted to know if anybody else did this in a similar way
There is a middle point between normal operating temp and "Kill your engine" temp. That is where I am at. At that point, engine will wear less. More up or down and will wear more. More up and it will wear in minutes.
I like the NSX, tight tight ride.

Thanks.

ripley's99 · 07-22-2005, 06:31 PM

i'm just curious, but have you shared this information with the MR2 owner's club, www.MR2OC.com ? i would be real interested to hear their comments, especially Bill Strong.

i personally own a '89 hardtop MKI MR2 that i do auto-x and i have no idea why you think the torque peaks at 6600 rpm....it peaks earlier at about the 5200 rpm mark, at least according to every dyno sheet i have ever seen. the hp peaks at 6300 rpm, actually.

this is the link to the dyno sheet from grassroots motorsports '85 Project MR2 here:

http://www.grmotorsports.com/news/07...s-the-dyno.php

not to offend you, but i think you are mis-informed on a lot of things, but you seem to know everything and don't care to listen to other peoples' points of view. so i'm not going to argue with you about engine temp. etc. - its your car so you do can as many experiments with it till it blows up.

anarkia1ces · 07-22-2005, 09:53 PM

Torque peak my friend also depends on exhaust type (Configuration/type of muffler/free flow or not) and cam advance/retard. Not all tune their engines equally.

SmokingTires · 07-22-2005, 10:11 PM

Quote:

Originally Posted by anarkia1ces

Torque peak my friend also depends on exhaust type (Configuration/type of muffler/free flow or not) and cam advance/retard. Not all tune their engines equally.

But yours is bone stock... And here's is bone stock... so they're the same.. And your exhaust system doesn't change your engines peak torque. It doesn't have that much impact on your overall performance