PDA

View Full Version : Heat Soak



Dan
07-17-2004, 04:54 PM
Has anyone ever used their roots type charger enough to experience heat soak? If so, what type of use are we talking about and what were the signs of it?

I am tring to find out if it might become an issure for me with my driving style. I know that if I got a charger I would be on it everytime I wanted to have fun. (read, probably a whole lot!)

I am hearing a lot about heat soak from a friend of mine who thinks that it might be a potential issue with a roots type blower.

Thanks,

Dan

PS: As always, let's keep the chat on topic and without reference to other products/types of blowers.

MikesMerc
07-17-2004, 06:57 PM
There is no doubt that adding any type of supercharger adds a lot of heat. Its a natural result of the compression process. Roots blowers in particular get very hot.

However, this is why the most OEM applications come with an inter cooler. This keeps the ACT (air charge temp) in control.

If you repeatedly beat on a Trilogy car for an extended period, there is indeed a small reduction in power due to heat. Although the heat is a bit more with a roots set up, this really is no different than any other engine configuration. And although you might see a very small performance loss when the blower and the motor is at its max temp, with the intercooler, detonation is never an issue.

BTW, don't get too worked up about the small performance drop I speak of when the motor/blower get toasty. You'd never notice it by the seat of the pants. Its something only a Dyno could distinguish.

MI2QWK4U
07-17-2004, 08:09 PM
I can attest from testing and experience that there is no problem with the intercooler handling the temps. I have a custom designed cooling system installed, and part of that setup is a Dakota Digital water temp gauge with two temp sensor units plumbed into the intercooling system. The guage will tell me BOTH the temp of the coolant coming straight from the intercooling unit in the intake manifold, AND the temp of the coolant going into the intercooler after being cooled by the heat exchanger and my cooling unit. I have just started testing this system, and broke it in at the Fun Ford Weekend in Norwalk last week. I have noticed that the Trilogy intercooling system is VERY effective! Norwalk was very hot and humid, and the intercooler maintained a very average ambiant temperature for the intercooler itself. Under hard use and wide open throttle, the hot coolant never got higher than 121 degrees, on the other hand, with only the heat exchanger being used, it managed to drop that 121 degrees to about 105 degrees for the coolant going back into the intercooler. After engauging the prototype cooling system in the staging lanes, that coolant temp was dropped even further to appx 89 degrees. That is a big deal....
Now today it wasnt nearly as hot around here, maybe 80 degrees, and the coolant never got higher than 87 degrees. The other day it was 68 out and I beat it hard to see what the temp would go up to....the hot coolant got to about 105, and after the intercooler it was 76 degrees. It would appear that just the heat exchanger alone drops the intercharger coolant temps 10-20 degrees depending on the weather, the prototype cooling mod appears to be able to drop it by another 10-20 degrees on top of that. This testing is far from rocket science testing, but Dakota Digital indicates the gauge and sending units are +/- 1 to 2 degrees in this temperature range. I have some more testing to do, more configurations of the cooling mod to try, but I am hopeful that the setup will help the car run better in hot and humid weather, in essance on a 90 degree day at the track, the car will run as if it was 60 degrees out. I for one can actually feel the difference it makes.
So rest assured that if you install an intercooled roots blower, such as the one that 40+ people have put on their Marauders, you shouldn't experience any heat related problems. I personally spin my Eaton harder than just about any other Trilogy blower, and like you, I am on it all the time! Hope this helps out, if not, ask more questions and we will do our best to answer them for you!
Dave

FordNut
07-17-2004, 08:23 PM
I can attest from testing and experience that there is no problem with the intercooler handling the temps. I have a custom designed cooling system installed, and part of that setup is a Dakota Digital water temp gauge with two temp sensor units plumbed into the intercooling system. The guage will tell me BOTH the temp of the coolant coming straight from the intercooling unit in the intake manifold, AND the temp of the coolant going into the intercooler after being cooled by the heat exchanger and my cooling unit. I have just started testing this system, and broke it in at the Fun Ford Weekend in Norwalk last week. I have noticed that the Trilogy intercooling system is VERY effective! Norwalk was very hot and humid, and the intercooler maintained a very average ambiant temperature for the intercooler itself. Under hard use and wide open throttle, the hot coolant never got higher than 121 degrees, on the other hand, with only the heat exchanger being used, it managed to drop that 121 degrees to about 105 degrees for the coolant going back into the intercooler. After engauging the prototype cooling system in the staging lanes, that coolant temp was dropped even further to appx 89 degrees. That is a big deal....
Now today it wasnt nearly as hot around here, maybe 80 degrees, and the coolant never got higher than 87 degrees. The other day it was 68 out and I beat it hard to see what the temp would go up to....the hot coolant got to about 105, and after the intercooler it was 76 degrees. It would appear that just the heat exchanger alone drops the intercharger coolant temps 10-20 degrees depending on the weather, the prototype cooling mod appears to be able to drop it by another 10-20 degrees on top of that. This testing is far from rocket science testing, but Dakota Digital indicates the gauge and sending units are +/- 1 to 2 degrees in this temperature range. I have some more testing to do, more configurations of the cooling mod to try, but I am hopeful that the setup will help the car run better in hot and humid weather, in essance on a 90 degree day at the track, the car will run as if it was 60 degrees out. I for one can actually feel the difference it makes.
So rest assured that if you install an intercooled roots blower, such as the one that 40+ people have put on their Marauders, you shouldn't experience any heat related problems. I personally spin my Eaton harder than just about any other Trilogy blower, and like you, I am on it all the time! Hope this helps out, if not, ask more questions and we will do our best to answer them for you!
Dave
So tell us more about the prototype cooling mod!

sailsmen
07-17-2004, 08:30 PM
Curious as to what is the "prototype cooling mod"?

MI2QWK4U
07-17-2004, 08:44 PM
I hinted a little bit about it with some pictures I posted. I was sortof waiting to see how effective it would/could be before posting about it. It needs some tweaking to be what I would consider a great success. Anyone going to Indy can see it up close as well as the dual temp gauge setup. I am hoping that it can actually have an impact on my 1/4 mile times, which some thought it did in Norwalk by allowing me to run times close to those I ran here at home in 70 degree weather. My goal is to take the edge off of the effect that hot humid weather has on any car. I will post more in a couple of weeks when I can make an intellegent report on it. There is a little info on this thread:

http://www.mercurymarauder.net/forums/showthread.php?t=10640

FordNut
07-17-2004, 09:00 PM
I hinted a little bit about it with some pictures I posted. I was sortof waiting to see how effective it would/could be before posting about it. It needs some tweaking to be what I would consider a great success. Anyone going to Indy can see it up close as well as the dual temp gauge setup. I am hoping that it can actually have an impact on my 1/4 mile times, which some thought it did in Norwalk by allowing me to run times close to those I ran here at home in 70 degree weather. My goal is to take the edge off of the effect that hot humid weather has on any car. I will post more in a couple of weeks when I can make an intellegent report on it. There is a little info on this thread:

http://www.mercurymarauder.net/forums/showthread.php?t=10640
Oh, yeah I remember that. Some of the guys with water injection systems have even setup a nozzle to spray a light mist on the intercooler.

MI2QWK4U
07-17-2004, 09:11 PM
I just put some pics of the gauge on that other thread.

http://www.mercurymarauder.net/foru...***.php?t=10640

Dan
07-18-2004, 03:38 AM
Dave,

Please keep up the work on your prototype and keep up the testing. Having hard data to verify a performance boost will be neat.

I am sure that the additional cooling will help longevity.

Best,

Dan

BillyGman
07-18-2004, 05:29 AM
On the street I don't believe that you'll ever be able to drive the Trilogy S/Cer enough to experience a noticeable power loss w/out first running out of clear open and unobstructed, and uncongested road unless perhaps you live somewhere out in the midwest where the population is very sparse and you have miles of open road w/barely any traffic at all.


Dan, in our homestate of Connecticut, there isn't anywhere that I've driven where I had the room to get into maximum boost pressure so much that I've noticed any loss of acceleration w/out first running into traffic or passing by Law Enforcement. So all of this is a dead issue as far as street driving goes no matter how hard you think you'll be on the gas pedal.

Everything Dave is talking about here is only of value for dragracing on the track, and when there are so few racers there that you can get runs in one right after the other, and/or while it's during an 80 or 90 degree day at the track in question. For street driving you reall ned not be concerned about any of this w/the Trilogy set-up. Like Dave said, it's quite efficient.

sailsmen
07-18-2004, 05:34 AM
Dave, thanks for experimenting and reporting the results. This is what allows us options to improve our MM.

Has anyone tried on the Trilogy kits;
a bigger heat exchanger then the larger one Lidio is using?
a bigger reservoir mounted outside the engine compartment?
a more efficient intercooler?

BillyGman
07-18-2004, 06:01 AM
Just so my previous post isn't taken the wrong way by anyone, I simply want to point out that Dave is obviously looking for a way to keep his already lightning quick Marauder in the low 12's at the track even during upper 80 or perhaps even 90 degree temperatures, which might even lead him to get into the high 11's some day during upper 70 degree temperatures, and there's nothing neccessarily wrong w/that effort at all. But it doesn't neccessarily mean that there's any great need for that for street driving, nor does that mean that there's an issue w/"Heat Soak" w/the standard Trilogy set-up.


That's all I'm pointing out here. On the street you're NOT going to notice any appreciable power loss. A highly competitve situation at the dragstrip during a very hot day is quite another story, and even then it doesn't mean that your Marauder will begin to lose so much power that you're going to start getting beat by cars that couldn't keep up w/yours on a cooler day, since those cars will also be moving slower in the extreme heat also wether they're supercharged or not.

Dave is looking for an edge, and that's fine. However it doesn't mean that there's a big problem w/heat soak while using the Trilogy set-up on your Marauder. I'm sure there would be IF the kit didn't include an intercooler since it runs atleast 9.5 PSI of maximum boost pressure. But again, just as Dave has already pointed out, the intercooler that the Trilogy kit comes with is quite efficient. Another point that I believe is noteworthy here is that Dave ir running more boost pressure than the Trilogy kit originally comes with. And in general, those higher boost pressures will create more heat.

So just keep in mind here that while Dave's viewpoints on this are very interesting, and I give him credit for his research, remember that his endeavor is to push the envelope of the Limits of this S/Cer system just as Lidio has also done so. But that doesn't mean that "Heat Soak" needs to be of any concern w/the majority of those who opt for the Trilogy S/Cer package even if they plan on racing their Marauder at the track.

MI2QWK4U
07-18-2004, 07:38 AM
I just want to make it clear that my project was in no way in response to a heat problem. As I posted earlier, now that I can monitor both temps on the coolant it was very apparent that the stock heat exchanger, pump, and intercooler are very efficient and do a great job keeping the coolant temps down. I have never felt any drop of from the effects of heat, other than the typical ones every car experiences in hot humid weather. What I am trying to do is minimize those effects.
Billy sort of hit that one on the head when he said "Dave is obviously looking for a way to keep his already lightning quick Marauder in the low 12's at the track even during upper 80 or perhaps even 90 degree temperatures, which might even lead him to get into the high 11's some day during upper 70 degree temperatures, and there's nothing neccessarily wrong w/that effort at all."
That is the goal, to take some of the heat out of the equation. I mean anyone with a Marauder will note a difference when it is 40 degrees out and when it is 95 degrees out, thats a fact of life. It is physics at work, cool crisp air wakes up any car, especially a supercharged car. By chilling the intercooler coolant it drops the ambiant temperature of the charge air entering the supercharger, it also dehumidifies that air as well.

BillyGman
07-18-2004, 12:12 PM
Thanks for your clarification and acknowledgement Dave. I fully understand what you're doing, but I just wanted to make sure that Dan did also, and that him and others didn't get the wrong impression. ;)