AHHHHH heat soak!!! solutions?
 

so I and a couple of friends went for an Easter "drive" it was the hardest i had pushed the engine since I've owned it. basically of 2 1/2 hours of back road driving with a few breaks here and there... but on the last say hour was when we were at the hottest and most demanding sections..... I noticed a lot of power lose due to heat soak (I'm assuming)

And I'm wondering if anybody knows of a way of getting more air to the intercooler.. I'm running an almost stock car other than the DP and opened intake box...

Soon I'm going to be upgrading the radiator and my plan was to modify the intake ducting to make a bigger opening and maybe block the heat that may be coming up from underneath.... haven't pulled anything apart to see if it's even possible but thought I would ask.

Couple of other ideas I've been playing with is 120MM fans on the back of the intercooler, pulling air.. Along with a separation baffle on the inlet side to break up any air buffer that may be sitting in front of the intercooler...

If people are interested in seeing results for this let me know, because if it seems to be valid ideas (and I have a lot more detail than this) I will perform some tests and attempt to get some results that are metered.



what do you think?

theres a guy on here than just mounted a fan to his stock mount i/c....haven't heard results but im sure it will help. the more air you can move through the engine bay the better.

im trying to find a link to that thread so you can see his setup.....


Drew

best way is to add a vented hood. but that takes away the nice factory look. I would add an upgraded radiator and do the fc fan switch mod. but you will still get heat soak at some point.

Jeff

yeah, I know I won't be able to get rid of it, just want to lesson it. It was pretty severe, just want to help it out.

And initially I wanted to do the vented hood, but yes, don't want to ruin the stock look, and I don't have the money to paint a hood either, which I wouldn't mind

best way is to add a vented hood. but that takes away the nice factory look. I would add an upgraded radiator and do the fc fan switch mod. but you will still get heat soak at some point.

Jeff

sorry double post!

Get a Power FC and get a tuner (or yourself with a Datalogit & wideband O2) to turn the fans on when water temps go above a certain level (depends on climate and how you drive the car, etc... The stock thermostat doesn't open until 80.5-83.5 degC (according to the FSM), so you could turn your fans on full time at, say 85 degC.

Look into the FAQs for how to do the "fan mod". That'll help cool off the motor when you shut it off.

EDIT: You may have already done these... BUT:

You may also want to block off the areas around the radiator with material to force airflow to the radiator. You can relocate your battery too... change out your OE pre-cat for a downpipe, etc... every little bit you can do to reduce underhood temps helps :)

So your car is heat soaking while you drive it ? ? ? I've always understood heat soak to be the phenomena that occurs when you stop and air ceases to move through the engine compartment, this should go away after a few minutes of driving (unless your in bumper to bumper traffic or it's just a stiflingly hot day) a vented hood allows the heat to leave much quicker than the factory one plus allows it to cool quicker once moving so I'm not sure what you'll gain with your mods while it's sitting still.

^

Agreed, maybe he is confusing "heat soak" with "air intake temp."

Water Injection should be the cheapest easiest solution. Also buy a FC thermoswitch($60.00) and install it so the fans come on much sooner.

wrong post

wouldn't it be both? the air temp close to the road is probably over 100 degrees, so yes it is intake temp, but at the same time, couldn't consider the same thing happening to the intercooler, I suppose I really do mean the intake temp. But I've seen what happens when a car doesn't get enough FLOWING air through the intercooler, but enough through the intake. to me this is also the problem I'm having. And considering it's all coming from that little duct in the car, it's going to create the same problem with both (though the resulting power loss may be a greater affect of the intake temp.)

An example would be is, I watched a dyno once where they put a blower in front of the ducting for the intake (cold air) and the dyno seemed low, so we told them to put a blower over the intercooler, and ran the dyno agian and the difference was about 25HP was a mazdaspeed 5 I think? What ever the 4 door mazdaspeed car that was out a few years ago.

And that's a single turbo, 4 cylinder, not a heat monster.

(Also to point out I was watching a development program on Porsche and they used the term "heat soak" when the car was moving, intercooler was in the wrong place)

Not to mention the concept of the intercooler works the same as the radiator, more air the better you cool..... So we can talk all day about getting coolant temps down, and trust me, I want to, but I'm also concerned that the intercooler isn't getting air flowing through it.

yeah sometimes I get that "power loss" feeling while driving around when it's a hotter day. I've been trying to do things to cool down my underhood temps. As far as the intercooler the only thing I can recommend is eventually go w/ a front mount if you don't wanna go w/ a vented hood. Hey I go down to Santa Maria a lot cuz of my fiance. We should meet up some time

Air Intake Temperature ~= Heat Soak.

There is no such thing as a Mazdaspeed 5. The Mazda 5 replaces the Mazda MPV which was a minivan no way to mistake that.

Probably what you are refering to is the Mazdaspeed Protege, far from the 5. I only say this because you said a few years ago. Or else it could have been the new Mazdaspeed 3.

What you said about Porsche, even if a car is in motion but there is no path for air to go to the intercooler than the metal would be absording the heat generated by the engine and retaining it effectively "soaking" in the heat.

Example of heat soak is after driving if I would look at my Power FC the car is standing still 70 degs celcius. But the car isn't moving however the metal IC and Intake tubes were "soaking" up the heat.

Maybe your IC just isn't up to the task of cooling your intake charge sufficiently on an elongated run.

It's the stock IC, what do you expect? It is way undersized for the application and to make matters worse, the stock intake robs air from it. The only way you are going to get a meaningful improvement is to go with a box-style intake (that no longer takes air from the IC duct) and a larger SMIC (or v-mount setup).

An FMIC would also give you much lower intake temps but then you have the penalty to engine cooling (one I'm not willing to pay).

He has a modified airbox, so it won't rob too much air from the intercooler, especially at speed. That being said, the small stock intercooler doesn't work very well. Better ducting may help, but the intercooler is really the problem.

yeah but having a v-mount w/out some sort of venting will create a lot of underhood temps (I had this debate w/ a friend) having a front mount w/out the vent hood is probably better than a v-mount vs. a v-mount w/ a vented hood.

^

Your reasoning makes absolutely no sense to me. This is not a FMIC vs VMIC vs SMIC war we already know who won that one.

That is like saying having a stock mount without some sort of vented hood is worse than having a FMIC you have obviously neglected the fact that their exists a radiator in your engine bay.

since many of you are refering to a vented hood, is there one that workes better than others (basically designed for functionality rather than aesthetics)

I like the Feed Style hood, but I was wondering if it would really helt reduce engine bay temps.

Sorry if you consitter this threadjacking...

I thought this might tie into the "heat soak" topic.

Gee, I'm glad you and your friend settled the issue for all of us by talking about it.....

V-mount has no temp problems with the stock hood whatsoever....try tracking your car with an FMIC....I guarantee you the v-mount stock hood car will still be driving long after you've had to pull off to avoid overheating.

Adam knows I want the car to look stock on the outside..... so a FMIC or v-mount is out of the question, until major upgrade incur. Right now we are talking about a setup thats a little more than stock and will remain that way for some time.

Like adam "cheap bastard" fits into my Mods, I don't cut corners, I'm just making the most out of the STOCK car.... so those are my guidelines... I up for replacing the SMIC with another bigger stock looking SMIC, but I think that will come when the ECU does.

Most of the money being spent will be on tires and track days...


so like i said.... heat soak.....

Also I'm worried, (and please back me up if anybody can agree with me on this) the air rushing through the intake duct gets pulled into the intake past the intercooler...... which to me would create and area of turbulence... or static pressure infront of the intercooler, and thus not forcing air through the intercooler. So I want to try adding a couple of 120MM fans to regenerate airflow across the intercooler.......

This is a VERY common problem... But not sure if this is the case with the stock ducting.....


So my idea is to create a new one, bigger and better.... with a baffle that will channel air to the intake system and to the intercooler... the baffle will stop the air from creating that static pressure......

Why try to improve something you know you will change.

I am a fanboy of the medium sized SMIC's I think they work perfect for a stock turbos, stock to 12psi pressure. Heck I am going on my second Pettit Coolcharge II old style.

But your fan idea is good. If you force it to go through the IC it will. I guess what you are hoping with the fans is to pull the air through the IC which would eliminate your problem?

I don't think fans are going to help very much with the stock IC, what type of fans are you talking about? When you say 120mm, I think of computer case fans!

I would strongly recommend water injection if you want to keep the stock IC setup AND want cooler intake temps.

You can spray whip cream over sh*t, but it's still sh*t underneath.

Having said that, the stock IC just isn't that efficient for this type of use. IMO, you'll have wasted efforts as larger SMIC's have proven that you can get enough air through the small opening for proper charge cooling.

I used a Blitz SMIC for a while and it performed well on the road course in some warm temps. They aren't made anymore, but you can usually find them for sale for good prices. That would allow you to still remain looking pretty stock and have the added benefit of a decent IC for your application.

they're actually oil cooler fans, designed for car batteries and moving the most volume (with less consideration of noise)

MAHJIK :: I will agree with, that going to a better intercooler, resolves the issue. It needs to happen. And I think the Blitz one, among others allow you to use the stock pipping. Which is a good thing.

But my point in this is to resolve the situation with little cost. avoiding the "money will fix it" idea. I'm not doing this to "fix something" I'm doing it to find a solution. Think of it from an engineering standpoint (which I'm not, more of a engineer-enthusiast )