Front mount on rear engined cars???

[1JZ]

Hey,

Question thats been bugging me for a while now.. may sound dumb but how do you have a front mount intercooler on a mr2 etc. seen a few with them and have always wondered how they did it.. do you run the pipes all the way under the car or what?

[RS13]

I have a reaaal old Hot4's mag, where there was an MR2 with the i/c pipes going through the cabin, where the passenger seat used to be.. just looking at it, I'd say there would be at least 4-5m of piping.. got lag?

[FST4RD]

The mr2 that i seen in a japanese mag that had a front mount used some sort of electric fan to keep the piping pressurised so there was hardly any lag at all........

[Malcolm]

very, very few mr2's have front mounts. I've seen them with w/a radiators all polished up to look like intercoolers.
The most common (non standard) placement of intercoolers in mr2 turbos is trunk mount, where they mount it flat on the floor in the boot, cut a hole in the floor, put a scoop underneath and vent the boot. Also a lot of people realise the significant advantages of w/a in a mid mounted car, but some just put $3,000 intercoolers into the stock side vent

[CozmoNz]

that jap one with the I/c (air to air) at the front was a drag car first of all, with a turbo the size of your head, so it REALLY didnt matter if it had a bit of lag...

once he got boost, hes keeping it .

[Akane]

very, very few mr2's have w2a intercoolers. Blah blah blah blah blah
The most common (non standard) replacement of the intercooler in MR2 turbos is side mount, where they mount it to the side vent, WITHOUT cutting a hole in the floor, and putting AN UGLY SCOOP underneath and vent the boot. Also a lot of people realise the significant disadvantages of w/a in a mid mounted car, but some just go ahead and spend $3000 into something that only cools as good as a ST205, weight heaps, wiring troubles, mounting troubles, and also lose the already lack of boot space.

[CozmoNz]

So akane, what IS the best way then

[Akane]

look at what me and Wildcard have now.

If you're building something that exceeds the capacity of what we have, then you're building a non street car.

If you're building a race car, then you shouldn't be asking in the 1st place.

[fivebob]

The most common (non standard) placement of intercoolers in mr2 turbos is trunk mount, where they mount it flat on the floor in the boot, cut a hole in the floor, put a scoop underneath and vent the boot.

Well that's the right way to do it, but most people are too stupid to figure out the best pressure distribution and end up flowing the other way, i.e. top to bottom

Also a lot of people realise the significant advantages of w/a in a mid mounted car

Care to quantify those "significant" advantages? Do they include extra cooling system drag, added weight, additional failure points, reduced efficiency, greater tendency to heat soak under prolonged boost?

While you're at it, would you care to explain why Ferrari & Porsche used Air to air I/Cs on their mid/rear engined cars, or for that matter why all the F1 turbo cars used Air->Air, with the exception of the early Renaults which used series charge cooling before dropping the Water->Air component after 2 races?

but some just put $3,000 intercoolers into the stock side vent

So you have knowledge of the actual flow through the stock vents, please share. I always wanted to know how much flow there is back there

Oh, and just what brand is the $3000 Air->Air I/C you were referring to? Sounds like a bit of ripoff seeing as Greddy or even Apexi are about half that price.

Mind you if you just want to build a dyno queen the Water -> Air is the only way to go, just connect it up to the tap, all the cooling you could want, can't drive very far though Or perchance you prefer to live your life 1/4 mile at at time, in which case you'd best take a large supply of party ice to the strip, so you can keep those charge temps down

[Carlos]

How about roof mount! Ok, may sound stupid, but if it worked for the Ford RS200 GpB rally car, why cant it work for anything else ...

[samlloyd]

or



or tmic
http://www.thespeedfactor.com/files/customers/Tim%20Hoyt/Tim/intake.jpg

[Malcolm]

Also a lot of people realise the significant advantages of w/a in a mid mounted car

Care to quantify those "significant" advantages? Do they include extra cooling system drag, added weight, additional failure points, reduced efficiency, greater tendency to heat soak under prolonged boost?

Alright, I didn't mean that it was better in all circumstances, but it does have many advantages, for instance the ability to make use of the area at the front of the car that sees a lot of airflow, while still maintaining very short piping lengths. Not to mention the heat sinking ability created by the mass and specific heat properties of water, meaning short periods of boosting (ie normal conditions for a road car) are absorbed without significantly increasing the water temperature. You might have to to explain what you mean by cooling system drag, are you talking airflow through the radiator? The added weight is less than most claim, my mr2 takes just over 3L of water, the pump, radiator and intercooler itself wouldn't weigh much more than a large trunk mount intercooler and piping. Also the long periods of boosting that create heat soak in a water/air system are the sort of things you'd find on a race track, and I certainly don't remember saying anything about w/a being superior for race use.

While you're at it, would you care to explain why Ferrari & Porsche used Air to air I/Cs on their mid/rear engined cars, or for that matter why all the F1 turbo cars used Air->Air, with the exception of the early Renaults which used series charge cooling before dropping the Water->Air component after 2 races?

Crikey anyone would think I claimed w/a was the be all and end all of intercooling in mid engined cars. I said it had significant advantages, I should've added depending on circumstances. In a circuit race car w/a certainly wouldn't be ideal but in a street driven mr2 it has definite advantages that shouldn't be overlooked.

So you have knowledge of the actual flow through the stock vents, please share. I always wanted to know how much flow there is back there

Oh, and just what brand is the $3000 Air->Air I/C you were referring to? Sounds like a bit of ripoff seeing as Greddy or even Apexi are about half that price.

Did I say anything about airflow through the vent? Did I say anything about side vent intercooler placement being bad? No, I definitely didn't. What I was getting at is that there are some very expensive and high quality kits available for getting the best out of the factory placement, without having to do much other than removing the old system and bolting the new one in. A guy I know paid about $2,800 IIRC for his Apexi intercooler, but that was a few years ago and given the changes in exchange rates since then I'm not suprised they're cheaper now, I wasn't trying to give an exact quote or anything....

Mind you if you just want to build a dyno queen the Water -> Air is the only way to go, just connect it up to the tap, all the cooling you could want, can't drive very far though Or perchance you prefer to live your life 1/4 mile at at time, in which case you'd best take a large supply of party ice to the strip, so you can keep those charge temps down

Man, you really take it personally when someone suggests something that you don't agree with...
But since you mention it, you'd be a fool not to consider w/a in a serious drag car when you can do exactly that, fill the system with ice and get ridiculously low intake temps for just a couple of kg increase in weight.

[skoty]

My mates 4agte powered aw11 uses something different; hes mounted the i/c above the rear windscreen. It may sound a unusual but it is a long and short cooler that doesn't stand out too much yet is very effective. Apparantly the ford rs200? uses this design?

[Malcolm]

How about roof mount! Ok, may sound stupid, but if it worked for the Ford RS200 GpB rally car, why cant it work for anything else ...

[sergei]

Water specific heat = 4.186 joule/gram °C
Air Specific heat = ~0.7- 1 joule/gram °C
Water thermal conductivity = 0.6 W/m.K
Air thermal conductivity 0.0257 W/m.K (@20 degrees C)

so here we can see that water can hold more heat and it can conduct it better, so water is superior coolant to air....basically water can cool more efficiently. Althou there are much more variables in there (ie limited supply of water, water is cooled by air)... it all depends on design of w/a i/c.

Personally I preffer idea of w/a i/c = less intake length. more efficient coolant used (althou I would use some liquid metal, like mercury or gallium)...

Yep my boss' RS200 has i/c above rear hatch (under scoop), funny thing is it is quiet compact..

[anthonym]

Man, you really take it personally when someone suggests something that you don't agree with...

Nah only when someone casts aspersions on his favorite windmill. Been there done that, still waiting for the pudding. In the meantime here's a pretty picture of one of those big fans fivebob likes so much .

[samlloyd]

back mount ic looks like a good idea. Apart from scraping on the drive going into pak'n'save

[CozmoNz]

theres an aw11 in dunedin (rally car) with the I/C mounted as the spoiler... (long and thin), anyone know how good this will work, if its certable? any downfalls etc.

also runs an SR20DET, so i suppose fabrication came easy for those chaps >.>

oh, and anyone know the measurement of the factory bov outlet? time to get wanky with a $30 filter and a $4 bath plug .

[willsf1]

Yeah like Skoty said ive roof mounted the ic on my aw11 . Yet to get the gte going but after running a boot mount with the sc setup i think its gotta be a better alternative. Finding speed is all about compromises!

[fivebob]

Man, you really take it personally when someone suggests something that you don't agree with...

Nah only when someone casts aspersions on his favorite windmill. Been there done that, still waiting for the pudding. In the meantime here's a pretty picture of one of those big fans fivebob likes so much .

Wondered how long it'd take you to bring that one up. BTW I'm still not sure you need big fans to do the job, but they would help. However it's largely irrelevant to street driven SW20s as most of them are struggling to make 300WHP, let alone anything that would challenge the airflow through the side vents.

It's not that I don't think that W/A has it's place, it's just that no one has yet shown that you can't get the cooling required by using a properly sized Air->Air unit mounted in the stock location. Instead of bothering to do adequate research on the topic, people assume that by the looks of it you can't get adequate airflow through the side vents, which is obviously not the case as the intake also has to breath through there.

And no, I don't get touchy when someone disagrees. However I do object when people post things without proof and expect their opinions to be taken as fact, or spew forth internet legend as though it was the one and only point of view to be considered. If you want to prove a point you need to provide supporting arguments, not state something like "has significant advantages" without at least stating what those advantages are, or indeed actually providing proof that they are advantageous at all

IMHO Water->Air has as many disadvantages as it has advantages, and, apart from drag racing and dyno queens, none of the advantages are significant. Seeing as I care about neither dyno figures, or living my life 1/4 mile at a time, I'll stick with the Air-> Air solution, though perhaps not in the stock location