Good Intercooler upgrade for T2

[city_cabriolet]

Hi all,

I'm getting my IC piping done and want to install a new Intercooler while i'm at it.

Anyone know of a good Top-Mount IC that fit's under the T2 bonnet? Eg. RX-7, WRX??? Starlet GT etc.

Cheers,
Luke.

[Brendan]

If you're going to spend the money on piping you may aswell move it to the front... much more efficient there.

I cant see a top mount (even if it is bigger) being much better than standard, it still has all that engine heat to fight with.

Brendan

[Colza]

Lots of quite fast cars DO come with top-mount intercoolers though. If STI think that they can get enough airflow to the top and benefit from the much shorter piping then im sure it is achievable. It would just be a matter of opening up a bonet vent (or two) and fixing up a duct to provide lots of cold air and take away the warmed air. Either way is gonna give you a noticable increase in power and the ability to crank the boost a little higher ;D cant go wrong with that!

[city_cabriolet]

I'm not going front mount. All the cars you see (besides city's) with front mounts have the turbo facing the front, not the back, therefore piping isn't 3 foot long.

Our little turbines have to work pritty hard when you've got front mount, increasing the lag and you have to up the boost just to make it feel the same as top mount (unless you upgrade the turbine which compensates). The IC on some peoples cars are more for show than anything else, we don't need HUGE front mounts.

Top mount only requires very small piping = less lag with standard turbo. I just want it more efficent, so i'm getting a bigger IC and adding foaming to underneath of bonnet to section off where the cold/hot air can go etc.

So anyone know of a good cheap top mount IC?

[Colza]

I had forgotten about the whole 'turbo at the back' thing. Definately with you on this one city_cabriolet!
If my intercooler was not bought for $4 from the scrap metal dealers and plumbed in with scrap pipe then it would probably be top mount too ::)

I think the previous list is probably a good place to start. Go for the newest design within your price range. Used coolers are FAR cheaper than new and work just the same. Remember that big is not essential with the City T: my crappy, old, just bigger than stock Mazda DOHCer cooler does a fantastic job! But i am only just above factory boost so you may be looking to a little bigger again.

[Brendan]

Colza most the quick wrx's are very quickly converted to front mount setups.  They come standard with a top mount because its all they need and its alot cheaper for subaru to make them that way.  Also the way the engine is setup there is ALOT of piping to a front mount so yup the lag factor is there.  The lag factor however seems to be overated.  Lots do come with top mounts, but lots more come with front mounts.

city_cab, the city turbo engine bay is one of the shortest you'll ever see, if done right there does'nt need to be much piping.  See the following example:

http://www.cityturbo.com/gallery/albums/albun58/Engine_Bay.sized.jpg

There is maybe another foot or two of piping over stock?  If you noticed much of an increase in lag between that and standard I'd be surprised.

Anyway I'm not trying to convince you of anything, just justifying what I said above

There is advantages in both situations... if you really are concerned about lag, go for a water to air setup.

Brendan

[city_cabriolet]

The cost of Water to Air outweigh the benefits.

That car pic isn't applicable because we all know that's a Hill Climb car running 18+ boost. That's why there's minimal lag (but stresses the turbo more than stock).

What IC is that but? I'm sure it'd fit in top-mount form (the bonnet hump is quite deep on the T2).

You don't care about lag with 18psi, but at 9 (which mine is currently running???) and even 12-13 standard boost, running top-mount or the example you gave, you will notice a difference.

What are you going to do with your T2? You going front mount?

ps. The WRX run small turbines, that's why Charles says a WRX Turbine can fit (and are a good upgrade) for our T2's. Running longer pipes than necessary severly increase lag with small turbines. Remember you've got a bigger intercooler to start with, it holds more air volume, then longer piping increasing the total air volume (in some cases by 2), this area has to pressurise, and it's not twice the length of time, but it's noticeable.

[Colza]

Some random comments both for and against :

I dont think the speed the turbine is allowed to spin up to in the end is in any way related to the time it takes to start spinning at an effective speed.

Although having said that a City Turbo racing at 18psi is hardly going to be running at low revs very often...

While a front mount City Turbo has very little piping, a top mount has even less. The barely noticeable lag us City drivers have is one of our few advantages we have over bigger engined cars, that little extra from the front-cooler is possibly the difference between a win and a loss.

Homebuilt water to air can be done quite cheaply if you dont mind getting a bit dirty ;D!

In the end, someone has to try it before we can really say anything. This is the old "bench racing" phenomenon returning.

[Kam]

I've got a Subaru Liberty top mount Water/air intercooler for sale if your interested. ($150) I've seen one fitted to a gen1 civic with a T2 engine!  I'm is Brisbane.

[Brendan]

That car pic isn't applicable because we all know that's a Hill Climb car running 18+ boost. That's why there's minimal lag (but stresses the turbo more than stock).

You don't care about lag with 18psi, but at 9 (which mine is currently running) and even 12-13 standard boost, running top-mount or the example you gave, you will notice a difference.

It does'nt matter if you are running 9psi or 18psi you are still going to have the same amount of lag... i.e. the time the turbo takes to spool up before reaching anything above atmospheric pressure.

I still think the whole idea of lag after big front mounts are setup is overrated.  After I put the front mount on my 200 I got a pressure increase even through another few foot of cooler and piping.  Not the best example as its a bigger turbo but you get the idea.
We'll be running a front mount in the T2.


Colza:

that little extra from the front-cooler is possibly the difference between a win and a loss

Maybe if you are starting drags below 1000rpm and then flooring it.  You should be revving up to a high rpm before taking off so the turbo is already spooling.  The difference between a win and a loss is probably going to more come down to the front mount being able to safely run another 2psi.

The barely noticeable lag we get in city's has alot more to do with running pissy little turbos that can spool up at the drop of a hat rather than the minimal amount of cooler piping.

Really if you are concerned about the extra lag, take off from the lights with another 500rpm, we are driving hypo little turbos here not barinas

Brendan

[BOOSTBOY]

Lag is governed more by turbine sizing and exhaust manifold design rather than intercooler piping lengths or diameters.  More often than not, the increase in intercooler flow by installing a larger core more than compensates for a small increase in pipe length when it comes to throttle response.  A turbo, even as small as that found on the city turbo, pushes a hell of a lot of air at a decent pressure.  Keeping this in mind, pipe lengths become almost irrelavent.

[Charles]

Hey guys,

Either setup will work, me I prefer the front mount. If you filip the intake plenum (or point it forward there is minimal pipework for a front mount (if you can do without your A/C). A good top mount will work, but sheilding it from other under bonnet heat can be a challenge. You can cut out the front of the hump to give it more air. Just make sure it is an intercooler not interheater

Also a wrx turbo on a city would start spooling at about 4500rpm so I would never recommend that, try a legacy turbo, they are small and will spool well. The GT17 is my choice but even that gives some lag.

[BOOSTBOY]

Id be trying the legacy BB turbo for sure, its smaller than the GT17 which, for me, is way too laggy for street use...

[city_cabriolet]

Kam, yeah give me an e-mail or tell me yours.

I've got family in Brisbane that can pick it up for me. I'm in Newcastle myself.

Others... OK i'm starting to see the light about front-mount. Keeping the heat off it is an issue. And i suppose the 3 foot of piping may be worth it when on long drives in hot weather, both protecting your engine with lower temp air and retaining HP.

What does everyone think about the Liberby Water/Air Kam has for offer?

[city_cabriolet]

oh, i'm not upgrading my turbo. It's in good condition at the moment, but sure, down the track i'll be looking into something like that Liberty BB  ;D