This is my question. If an air to water intercooler was used in a fiero, could you use the stock coolant lines and tap off of them? I can't see a problem with this setup, if the radiator and water pump were accommodate for it. Please any info on this I would love.

You don't want HOT water in the intercooler, you want COLD water. You need a completely sealed and separate water system that takes as much heat out of the system as possible. The turbo produces hot air and the cold water in the intercooler takes the heat out of the air. Colder air = more power = less chance of detonation.

[This message has been edited by Hudini (edited 03-14-2007).]

I am considering a water to air intercooler on my car in the future (once its running). I would agree that you really do not want to tap into the engine cooling system since the temperature of the fluid will be between 160 and 210 degrees. The air temperature under pressure could be close to these temps if you are running 10 psi boost or more. As a result you will see either no cooling effect or the air will actually be heated.

The really trick setup would be to run your AC compressor to the cooler with an expansion valve installed. You could then use the AC to cool the charge.

I ran a air IC and it was not that efficient. Its was the popular Saab model and I mounted it right about the rear engine vent. Unless you use some kind of fan it is not good at all, in fact the IC got hot to the touch after driving around. Then I mounted a water IC and there was a huge difference. Understand, after a while there is little in performance from a water to just, mainly because after a while the water will reach ambient temp, but with the water you can add ice for a super cooler effect. And, water IC is pretty much a must for a rear mounted engine.

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87 Fiero GT (3.2 Turbo)
E-mail: david88@peoplepc.com
www.angelfire.com/pa5/davidfiero/

You can get good intercooler benefits from mounting it down low laying flat in front of the forward cradle cross member and attaching a small scoop to direct air up into it. The vent area is the worst possible location simply because the heat from the engine bay is drawn through them. A water/meth injection kit set to come on at a particular psi along with an intercooler or alone would probably be much, much more effective given the engineering required for a hydro intercooler.

quote Originally posted by RotrexFiero: I ran a air IC and it was not that efficient. Its was the popular Saab model and I mounted it right about the rear engine vent. Unless you use some kind of fan it is not good at all, in fact the IC got hot to the touch after driving around. Then I mounted a water IC and there was a huge difference. Understand, after a while there is little in performance from a water to just, mainly because after a while the water will reach ambient temp, but with the water you can add ice for a super cooler effect. And, water IC is pretty much a must for a rear mounted engine.

you are never going to get air below ambient temps without a CO2 or nitrous sprayer, so why the concern getting water below ambient?
the saab intercooler is ont he small side and where you had it mount it was an interheater taking the hot air form the engine bay
you can get cool air form the bottom of the car but its riskier with stones and such - air/ water really is the easiest/best solution for the fiero

quote Originally posted by Kohburn: you are never going to get air below ambient temps without a CO2 or nitrous sprayer, so why the concern getting water below ambient? the saab intercooler is ont he small side and where you had it mount it was an interheater taking the hot air form the engine bay you can get cool air form the bottom of the car but its riskier with stones and such - air/ water really is the easiest/best solution for the fiero

I don't know Kohburn, it would be pretty difficult for a rock to turn near 90 degrees and move upward with sufficient enough momentum to damage the IC in a flat mount location with a small scoop to skim air passing underneath the car, I never had trouble with my Saab IC and it hung partially in the air stream instead of laying flat. I believe the risk of damage is no greater than what a front mount IC experiences head on since the same debris has to first be low enough to get past the bumper and then be small enough and bounce at the right time to have a chance at getting into a small scoop. A small fan can also be mounted to the IC to help at speeds to low to generate good flow. The water for the hydro cooler has to be cooled sufficiently so that will involve a good bit of plumbing to mount the radiator in front to cool the condenser in the back. It has the potential to cool better than air/air but I doubt "easy" is involved anywhere in the process.

From what I have read the water/meth injection alone will provide an exceptional solution and if used only at a boost level where it is really needed would not require refilling frequently.

I think this situation calls for formulas and computations. I like doing the numbers, it can make a big difference when applied through out including choosing proper exhaust pipe dia, you can have to large a pipe even for a turbo and contrary to popular belief scavenging does occur after the turbo.

i never said that i wouldn't put an air air down there. just that air/water is the best solution. I preffered to go air/air due to the faster response time and i have a fan on there to avoid it heat soaking when sitting still.

quote Originally posted by Hudini: You don't want HOT water in the intercooler, you want COLD water. You need a completely sealed and separate water system that takes as much heat out of the system as possible. The turbo produces hot air and the cold water in the intercooler takes the heat out of the air. Colder air = more power = less chance of detonation.

How hot is the charge temp of a system without a cooler? 400°? close to 400°? then divide that by 2 = 200°.
http://www.opcon.se/index.a...ge=1&langID=2&cID=15

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Cadillac Tech
ASE MASTER TECH since 1988

86 Northstar Fiero
85 RX7 former SCCA car
56 TR3 small mouth 6.0L
A.J. Whiteley

quote Originally posted by AJxtcman: How hot is the charge temp of a system without a cooler? 400°? close to 400°? then divide that by 2 = 200°.

yes - good point - hot/cold is subjective. while coolant system may seem "hot" to the touch - it is cool compared to a turbo. probably why plain old coolant is used to cool a water cooled turbo, eh? I suppose you COULD use a oil cooler and a pump and have the water cooling for turbo be completely self contained.

holy hell i hope its not 400* that would be beyond the operating temp of most of those silicon charge hose couplers.
charge temps get into the mid 200's. the ability of an intercooler to retuce the temp of the intake charge is a simple BTU transfer, and the colder the transfer medium the faster it can shed heat.

The 4.4L supercharged engine runs 12 psi out the compressor and the cooler reduces the temp so much that it drop the psi down to 9.5 psi at the intake valves. I have read that 400° charge temp is not that abnormal coming off of 1000° exhaust temp.
This may be a high load application.

Turbos when properly matched tend to be a good bit more efficient than superchargers and under those circumstances the aircharge doesn't get that high (400 deg) without running considerably hight boost pressures. The reason a lot of production cars past as well as pro recommendations exclude intercoolers at 7psi and below is because usually the cooling gained is not enough to produce a net appreciable power gain when the inefficiency of intercooler flow is deducted. For example if adding an IC at 7psi is going to cause a 1-1.5 psi pressure drop due to resistance then it's not worth it since at that boost level on a properly sized turbo for the engine it's not going to add an excessive amount of heat so that when it's cooled you gain enough power increase to overcome the power lost in the IC.

That's why the compressor maps are so important when choosing a turbo, so that when you are really serious about getting the best power for your operating range you opt for a turbo thats going to put you in the 70% plus flow island at max boost for the higher range you plan to run the engine in. It may start out hot but as you approach higher efficiency the charge gets cooler.

I don't have the website address at the moment but there is a Stealth site with some exceptional calculators for all aspects of engine dynamics and it gives you an idea of temps to expect based on your settings, 400 deg is high for the low pressures usually run on our engines.

My service manager came from a Mitsubishi dealer. He had a customer with a 3000 GT that ran 1300° out of the turbos. the customer had EGT sensors all over. He was running nitrous and raced the car. His name was Doctor Mits or something like that.

quote Originally posted by AJxtcman: My service manager came from a Mitsubishi dealer. He had a customer with a 3000 GT that ran 1300° out of the turbos. the customer had EGT sensors all over. He was running nitrous and raced the car. His name was Doctor Mits or something like that.

A 1300* EGT is small beans. A 1300* intake charge temp would mean your engine is only going to be internal-combustion for a very short period of time.

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My Web page | The Turbo Super Duty Build.
You know that little voice that says it can't be done? I duct-taped mine's mouth shut and pushed it down a flight of stairs.

Is there a generally accepted boost level where an intercooler is needed? Can an intercooler ever hurt performance, say at 5-6 psi?

quote Originally posted by Hudini: Is there a generally accepted boost level where an intercooler is needed? Can an intercooler ever hurt performance, say at 5-6 psi?

The answer to both of your questions are in Joseph Upson's last post..

[This message has been edited by Steven Snyder (edited 03-17-2007).]

quote Originally posted by FastIndyFiero: A 1300* EGT is small beans. A 1300* intake charge temp would mean your engine is only going to be internal-combustion for a very short period of time.

He had EGT sensor in the air charge leaving the turbos that read 1300°. I was told this guy was sponsored by Mits. The Mits dealer did some work on the car. One time they installed some cams sent over from Japan specially built for his application from Mits. 1300° is what I was told I never saw it personally, but I saw the car being loaded into a trailer coming out of a warehouse once. that is 1300° not 1300*

quote Originally posted by AJxtcman: He had EGT sensor in the air charge leaving the turbos that read 1300°. I was told this guy was sponsored by Mits. The Mits dealer did some work on the car. One time they installed some cams sent over from Japan specially built for his application from Mits. 1300° is what I was told I never saw it personally, but I saw the car being loaded into a trailer coming out of a warehouse once. that is 1300° not 1300*

They are leaving out some very important parts of the story, not saying it's not possible however there are parts in between the turbo and intake manifold that might have problems with that kind of temperature. I don't recall the melting point of aluminum but that has to be getting pretty darn close.

I just ran a mock up on a 3.9L 7000rpm, 25psi boost, 60% compressor and intercooler efficiency which is conservative and was only able to produce an outlet temp before the intercooler of 372 degrees which is very conservative at 25 psi. 7 psi on the same background only generated 184 degrees.

[This message has been edited by Joseph Upson (edited 03-17-2007).]

quote Originally posted by Joseph Upson: They are leaving out some very important parts of the story, not saying it's not possible however there are parts in between the turbo and intake manifold that might have problems with that kind of temperature. I don't recall the melting point of aluminum but that has to be getting pretty darn close.

That is the point. It is all about reducing air charge temp. I asked two guys that might have an idea of uncooled air charge. The first answer was 450° and you saw mine above at 400°. Then I ask our manager a younger guy that has seen a lot more turbo performance cars than I have. When he said 1300° I told him he was off by about 1000°. Lets stick to the 400° to 500° range. Look at cooling that temp down to 100° to 150°. I feel this would be possible with a inter cooler. I am sure it can be done with a water type cooler. Compressors either turbo, impeller, screw, pistons "shop type". All heat air. Even an AC compressor gets hot. My shop compressor in my garage get hot and I have a box fan to help it cool and prevent damage. As stated above the 12 psi leaving the Northstar supercharger is cooled down and reduces the pressure to 9.5 psi.
.

If someone has a boost gauge I would like to know the PSI leaving the turbo and then what it is at the intake manifold after the inter cooler.

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Cadillac Tech
ASE MASTER TECH since 1988

86 Northstar Fiero
85 RX7 former SCCA car
56 TR3 small mouth 6.0L
A.J. Whiteley

quote Originally posted by Steven Snyder: The answer to both of your questions are in Joseph Upson's last post..

He hinted at 7 psi, but never actually posted that because he also talked about a pressure drop of 1-1.5 psi. I guess my question should have been something like: at what point does an intercooler become useful? I ask because I saw an air/water intercooler advertising a .5 psi pressure drop. I'm shooting for 5-6 psi on a T3 so I would not need one. But I still want one. I'm thinking I would have to increase the boost to see a gain from the intercooler. Therefore, where is the break even point? Its probably like everything else, it all depends on the individual components.

I installed an intercooler on my 7psi setup and noticed decreased response due to the restriction, 10psi is the most suggested minimum psi to run an intercooler that I've seen.

Ok, just what I was looking for. My little T3 won't put out that much so I can hold off on the intercooler until the funds improve.

air to water intercooler all the way unless your drag racing then a air to air with meth injection will work great for just the strip and about 30 psi but for daily driver with like 12psi air to water will work wonders. I plan on converting one of the air to air intercoolers I have into a really efficient air to water intercooler with a reservior big enough for ice or dry ice and after the intercooler run it into a multi cooler with a fan on it then back to the reservior. I think that would be a good way to lower the temps with putting ice in it on those hot days or when I am running it hard and it will be easy to make room for it in the really tight engine compartment of a fiero. I have a customer with a 36x22 air to air intercooler 5.0 mustang injectors t3/04 turbo on a rotary and runs it daily at 15psi and on those fun days at like 20+ but I know its enough to go through a trans mount about every month and he has no problems except the flame thrower of a dual exhaust that gets about 3 feet of torch at 7000 other than that its a easy 10sec car and on the stock tires it will get 5th gear chirp at 110+.

another feature no one has mentioned..
air to water intercoolers are about 7x more efficient so you dont need to go as large..

on a hot day stand in 80 deg air and see how cool you get...
now jump into a 80 deg pool... - n'uff said

depending on your plans.. water/alcohol injection is less money and much easier to use.
and with the progressive controlers these days... it IS rocket science but its easy to calibrate and use


here is one of many commercialy available kit manufacturers with their own bulletin board no less lol
http://www.alcohol-injection.com/
http://www.alcohol-injection.com/forum/

here is an online calculator that allows you to play with intercoolers as well as diff turbos.
it also has inputs for water/meth calcs as well
http://www.not2fast.com/tur...ary/turbo_calc.shtml

oh btw when you save it as a favorite it saves your parameters as well into the link !


I have links to tons of resources... feel free to ask

enjoy


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87 Fiero GT 5sp with Vortec L35 4300 Turbocharged V6
Bully Stage 2 clutch
Syclone intake manifold and engine management with Moates adapter and chip burner
Air/water intercooler and Devil's Own progressive water/alky injection
50lb injectors, 3 bar map sensor, Walboro fuel pump and Jabasco Intercooler pump
LM1 wideband on custom manifolds and 3" stainless exhaust system
T31/T04B S4 turbo with a Super T61 in the box
S10 caliper conversion.
Murphy's Constant Matter will be damaged in direct proportion to its value
Murphy's Law of Thermodynamics Things get worse under pressure.
Arthur C. Clarke "Any significantly advanced technology is indistinguishable from magic"

[This message has been edited by vortecfiero (edited 03-17-2007).]

I spent a lot of timing plumbing my Saab intercooler to the turbo and later regretted it. It created a huge restriction, and like mentioned I dont believe cooled much of anything.

There are some nice water ICs on Ebay but they are very expensive. The model I got for around $100 was very large, 3" piping, but flows nice. I only used it for a couple times, but planning on more extensive time with it this summer. Right now I am running no IC, but the temps outside are very cold.

depending on how efficient the compressor is with your setup...
you may be able to run up to 5lbs of boost on low octane gas
with out using an intercooler

Not to hi-jack this thread but does anyone know where I can get some 3in flex tubing, has to be heat resistant. I only need a few feet. I searched online but can not find anything, and I dont want to go with silicon connectors, mainly because of the cost and I still have not finalized the location of IC and turbo. Any help would be appreciated.

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87 Fiero GT (3.2 Turbo)
E-mail: david88@peoplepc.com
www.angelfire.com/pa5/davidfiero/

quote Originally posted by RotrexFiero: Not to hi-jack this thread but does anyone know where I can get some 3in flex tubing, has to be heat resistant. I only need a few feet. I searched online but can not find anything, and I dont want to go with silicon connectors, mainly because of the cost and I still have not finalized the location of IC and turbo. Any help would be appreciated.

Some of these maybe the same, not sure which is which but I found some of the best prices I've seen on silicone hose at a couple of these:

http://www.hightempsilicone.com/
http://shopping.netsuite.co...c.7/category.8253/.f
http://www.siliconestop.com...ath=3&products_id=12
http://www.siliconeintakes....4d2756cc0e852d2d5a7f

it would take a 100* day with an engine pushing 60psi at an un-intercooler turbo efficiency of only 50% to get low/mid 400's
seriously - do some math - even at a normal 70% efficiency it takes 120psi boost to hit 460*...
in order to hit 1300* charge temp you would have to run the intercooler on a 115* day pushing 130psi from a turbo at only 20% efficiency
and I've never seen a turbo that could push that kind of pressure without air-stalling or exploding.

some numbers that would be common are a 98* day, 20psi, and 65% efficiency. and the calculated output temp is 193*
if you are running an efficient turbo in its sweet spot pushing those 20 psi at 73% efficiency then you are looking at 177*
intercool that at lets say 60% and you get 120*

quote Originally posted by Kohburn: it would take a 100* day with an engine pushing 60psi at an un-intercooler turbo efficiency of only 50% to get low/mid 400's seriously - do some math - even at a normal 70% efficiency it takes 120psi boost to hit 460*... in order to hit 1300* charge temp you would have to run the intercooler on a 115* day pushing 130psi from a turbo at only 20% efficiency and I've never seen a turbo that could push that kind of pressure without air-stalling or exploding. some numbers that would be common are a 98* day, 20psi, and 65% efficiency. and the calculated output temp is 193* if you are running an efficient turbo in its sweet spot pushing those 20 psi at 73% efficiency then you are looking at 177* intercool that at lets say 60% and you get 120*

Precisely why I kept using the terms properly matched because the higher the efficiency the lower the heat generated and I still have my doubts about the hydrocooler in this application, it's not going to cool better just because it uses water for better conduction, blowing air through water filled core tubes is not the same as a person standing in 80 deg air vs. 80 deg water simply because the air doesn't touch the water in the evap core, it's touching the metal that is touching the water so the same conduction process found in air/air cooling is taking place only the core is a little cooler due to the use of water.

There is also the need for a sufficient size condenser to cool the water before it goes into the evap core back at the engine. I think if the appropriate math is applied based on the boost pressure intended in this case you will find that the added weight, plumbing and size requirements will make a good size air/air intercooler or water/meth injection alone more practical in the end. Does anyone know how much space the Syclone/Typhoon system takes up.

[This message has been edited by Joseph Upson (edited 03-19-2007).]

I dont know, but with my SAAB IC mounted in the drivers vent, I get ~95* IAT temps normaly, I forget the actual number, but the highest I could get it running 0-100 sprints repeatedly was under 120*. I also dont remember the ambient temp, but it was something between 60 -80 and im thinking it was a warm day when I was checking this.

Mounted there, it seems more like a heat capacitor. It will absorb a lot for a bit, then some for a while, but it will then also hold that heat without proper airflow. Since the test, Ive put a fan on it as well as ducted the 1/4 scoop to force air over it. I havent re-run the test to see yet, but I will when it warms up. (I've also mounted a CO2 fogger under it, I have no idea what thats going to do)

But all this jaz about it will heat the charge under normal conditions just doesnt happen. At cruising ( IE under vacum) the compressor should not be imparting any heat to the charge, so you're blowing 60-70* air through the IC, you might pickup a degree or two from engine heat, but at cruising that (theoreticaly) should actualy help fuel mileage, but certainly wont hurt since you arent pushing it. Then when you romp on it, your IC is still at pretty much ambient tempature, because the air flowing through has kept it there, and once you let off, the air flowing through it cools it back down. before I put the fan and scoop on there, I could hop right out of the car after cruising and put my hand on the IC and it would be cool to the touch.

Now, this is not how an IC is supposed to work, but it demonstrates that mounting it there is not going to raise your intake temps 90* or anything. Without any sort of airflow over the IC, you're not going to gain much once its raised to meet whatever temp the compressor is putting out, so you really need to plumb it up with positive airflow to get good effect out of it.

as far as 1300* output temps, I would want to see that, but not stand too close to it, seems to me that would melt the couplers and anything plastic, if not the aluminum in the IC itself. On a related note, how hot does air have to get before it becomes incandescent(SP?) that is, glows?

I had an IDL course this morning on Engine updates. I found this interesting.

quote Originally posted by Kohburn: it would take a 100* day with an engine pushing 60psi at an un-intercooler turbo efficiency of only 50% to get low/mid 400's seriously - do some math - even at a normal 70% efficiency it takes 120psi boost to hit 460*... in order to hit 1300* charge temp you would have to run the intercooler on a 115* day pushing 130psi from a turbo at only 20% efficiency and I've never seen a turbo that could push that kind of pressure without air-stalling or exploding. some numbers that would be common are a 98* day, 20psi, and 65% efficiency. and the calculated output temp is 193* if you are running an efficient turbo in its sweet spot pushing those 20 psi at 73% efficiency then you are looking at 177* intercool that at lets say 60% and you get 120*

using the online calculator in my reply above... I think you need to add the 193* to the ambient temps

I got the following

80* day
65% eff compressor
15psi boost
temps out = 288* (no intercooler)

which is pretty much what I saw when experimenting with my setup
hope this helps

Put it up front and use a fan the long lines back to the engine will only add to the heat disapation. If your not running really high boost, like 18 - 24lbs and air intercooler placed in the right spot with a good fan should surfice fine.

quote Originally posted by Kohburn: i never said that i wouldn't put an air air down there. just that air/water is the best solution. I preffered to go air/air due to the faster response time and i have a fan on there to avoid it heat soaking when sitting still.

Would tipping the front of the IC up some help the under car air flow through it better while the car is moving? Or is it not a problem and I am just trying to think to much?

[This message has been edited by AJxtcman (edited 03-24-2007).]

Check this article out about water/meth injection it gives a great indication of its potential. I certainly intend to use it, it's amazing how something as simple as a fine mist of water or methanol can take as much or more than 50 degrees of heat out of your boosted intake charge and make 92 octane function as if it were 105 octane fuel.

http://www.geocities.com/rad87gn/tech/alcohol.html

Water and meth inject was used way back WWII on fighter planes like the ME-109 and lots of others it does work but has few drawbacks like complexity and another fluid level to keep track of.