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Discussion Starter #1
Just out of curiosity, how much air actually passes over the engine lid compared to the side vents? The reason i ask is because the top mount intercooler design in THIS thread really apeals to me, but if there's enough airflow over the engine lid I might try an improvement on it. It doesn't seem like it would be all that hard to make a custom scoop for the engine lid, that had an attached shroud to close off the IC (like a WRX top mount). You could then stick a puller fan onto the bottom of the intercooler and make a defuser to draw the passed through air off. Am i making any sense to you guys? Like i said, It depends on how much air comes over the engine lid though.
 

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Hmm....

If I understand what you're saying, you're talking like air passes through the engine lid from the top of the car. This isn't the case. Air comes from under the car up through the engine bay and passes through the engine lid moving up. So I'd say it's safe to say that a lot more air passes through the engine lid than the sidevents because:
Air through engine lid = air from left sidevent + air from right sidevent + air from underneath
Roughly speaking of course. ;)

I don't know if I understood what you were asking, but I thought I'd throw that out to clarify anyway. That intercooler setup intrigues me too, by the way. :)
 

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Kenny's right .. I've seen a toyota diagram (of the mr2) showing main air flow entrances and exit's (cant find the damn diagram now), main entrances are side vents(hence the intake on one side, and IC on the other) and under body. Exit is the engine lid. The top mounts that I would recommend, that appear to work very well, are the ones from the alltrac!, they are Water to air, not air to air(I think if you search you will find details on the setup). I dont know how efficient the one you are talking about is, due to the air hitting it may already be hot/warm(if its coming off the engine. If it's coming from that side vent it will be cold, but how much direct air is being blocked by the intake ?... hmm ..now you got me curious :)
 

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hawkmn said:
I dont know how efficient the one you are talking about is, due to the air hitting it may already be hot/warm(if its coming off the engine. If it's coming from that side vent it will be cold, but how much direct air is being blocked by the intake ?... hmm ..now you got me curious :)
that's why it's placed on that side of the engine bay...it's farther away from the hot exhaust manifold on that side and is not above it...i've long been considering building a top mount a2a setup like this, but i won't use the same intercooler if i do, i'd find an aftermarket one in proper dimensions...also, some people relocate the intake to the other side when doing a setup like this...just FYI
 

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CT20b Drifter said:
i see the mr2s with tmic have their core mounted to the bottom of their trunk and a hole cut out with a scoop under all that, i saw multiple settups like this in my hyper rev and it really makes sense. also i saw some oil coolers mounted under the motor with a shroud.
I actually don't know that the out the bottom of the trunk is the best spot. That's dirty air, that is also heated from the engine and the pavement. I think the better set up is to have the air coming in from the top, as most do, and then have it exit out the rear somehow with the aid of fans.
 

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I'm in the same boat for researching intercooler setup's. And I think the best option (other than a good aftermarket side mount) is a W2A IC. Remember we are considering air charges while the car is moving, what about stand still, the whole engine bay heat's up evently because there is no air moving through it .. fans may assist .. but if you are going to do a DYI, why not W2A .. just my 2 pennies!
 

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I still don't see why the top mount ic would be more beneficial. Even though there would be more air flow, wouldn't thermal equilibrium and the fact that hot air rises create more heat by the top of the engine bay, than the air that comes directly from outside and is funneled into the ic via the side vent?
 

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mr2biker91 said:
I still don't see why the top mount ic would be more beneficial. Even though there would be more air flow, wouldn't thermal equilibrium and the fact that hot air rises create more heat by the top of the engine bay, than the air that comes directly from outside and is funneled into the ic via the side vent?
agreed ! .. that's why W2A would be best for any engine bay IC (again my 2 cents) . If you want a good A2A.. trunk mount would be the best.. depends on HP goals too!

the choices :eek2:
 

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I disagree and here's why.

When driving down the road, there side vents and under the car are a higher pressure than the engine lid. I have taped small threads on the engine lid while driving and found that they are either pointing towards the front of the car or sticking straight up. My design is to have my IC on the driver side like the link in the first post with ducting from the side vent and from a scoop that I'm going to make that will be under the car. This being ducted to the IC with the engine lid as the exit is in my opinion going to make for some excellent airflow. I'm in the proccess right now of putting it together.

Steve
 

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hawkmn said:
agreed ! .. that's why W2A would be best for any engine bay IC (again my 2 cents) . If you want a good A2A.. trunk mount would be the best.. depends on HP goals too!

the choices :eek2:
I haven't really looked into how a w2a works, but is the assumption that the colder water draws the heat out of the air to make the air colder? In that case wouldn't the water have to be colder than the incoming air?


I think this weekend I will do some test with a digital thermometer, just to see were the coldest air gets to.
 

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mr2biker91 said:
I think this weekend I will do some test with a digital thermometer, just to see were the coldest air gets to.
Proof will win! .. let us know your results .
 

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hawkmn said:
agreed ! .. that's why W2A would be best for any engine bay IC (again my 2 cents) . If you want a good A2A.. trunk mount would be the best.. depends on HP goals too!

the choices :eek2:

a2w is the best for cooling, i don't think that can be debated, really...the problem with it is that you will add lots more weight (water reservoir, pump, etc) and you most likely will hack up your trunk unless you mount it in the front someplace...the problem with trunk mount setups is that the intercooler piping has to be so much longer and will make significant amounts of turbo lag...also, again, you have to hack up the trunk and you will make it virtually useless (the trunk)....for me, i think a2a would be best for me...it's better than side mount because you can have a much larger surface area which should help cooling quite a bit, and you should be able to get just as much airflow as a side mount if you work it right with shrouding and possibly moving the intake to the other side...
 

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Would it be logical to have a intercooler under the car but with something to protect a bit so that it wouldn't get to battered up from debris. That would be an interesting setup. Something similar to the oil cooler under the car.
 

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Discussion Starter #17
Brucelee281 said:
Would it be logical to have a intercooler under the car but with something to protect a bit so that it wouldn't get to battered up from debris. That would be an interesting setup. Something similar to the oil cooler under the car.
Thats actually quite a good idea. Mounting the intercooler by the transaxle would introduce quite a lot of air, and to be honest, you'd have less debris than a FMIC sees. You'd just have to locate it away from the turbo, sort of by the intake. That and it would require more piping, which wouldn't necessarily be a good thing. I might try a transaxle located intercooler if i'm not happy with the top mount setup.
 

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I looked at that set up and in my opinion it would require a lot of piping. Probably more so than a trunk mount.

What's wrong with ducted top mounts? If you think about it, a properly ducted top mount would get the same amount of airflow as a bottom mount. Plus a problem with a bottom mount would be you'd have to build a scoop on the IC to capture and direct the airflow up through the IC. This would eat up a lot of ground clearance.

Steve
 

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Considering the direction of the air flow in the engine bay, the only reasible ways I see to make ducts for a top mount are:
1) Have a duct coming from a sidevent up to the intercooler, but then you might as well just mount the intercooler in the vent.
2) Have a scoop under the car coming up to the intercooler, but considering how crowded the bay is, that would be insanely messy to run, if it is possible at all.

I suppose you could combine the two ideas to increase airflow. This is all speculation though, can't really say if it would help or not until it's tried and properly measured.
 
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