intercooler type and placement

[Rabbit TD]

What would be the easiest method and what type of intercooler would be the easiest to hookup on a Rabbit TD.  I would like to keep it in the engine compt. to keep the plumbing as short as possible and to help cut down on lag  and it is not going to have a boost over about 15 psi.  I looked at the siliconeintakes site and their prices are good but they all seem a little too large for me to use  where I would like to put it.  Are the ones with the inlet and outlet on one end easier to hookup and what is the most common method of getting air to an underhood type.  I saw someone mention the Saab Blackstone intercooler and it is one with both hookups on one end from the pics. I saw and ebay has some of them right now.  Anyone ever done this and have any hints what to or not to do.
Any recomendations which one and where to best put it would be appreciated, Thanks

[TurboJ]

Two options really, how to get airflow to a engine compartment -installed I/C. Either a hood scoop, or a tube from the front of the car. You can also improve things by fitting an electric fan to allow colling when stationary or driving slow.

[bevboyy]

Keep in mind the amount of pressure drop with the blackstone intercooler. If you using one under the hood, I would look into one off a Ford Thunderbird Turbocoupe instead.

[dillenger1]

eagle talon or eclipse gts both have a nice welded alluminum ic.

[monomer]

I'm using a crossflow STI top mount...

[ahto42]

Keep in mind the amount of pressure drop with the blackstone intercooler. If you using one under the hood, I would look into one off a Ford Thunderbird Turbocoupe instead.

you can take a new wastegate signal after the intercooler, and there is no pressure drop.

[jtanguay]

Keep in mind the amount of pressure drop with the blackstone intercooler. If you using one under the hood, I would look into one off a Ford Thunderbird Turbocoupe instead.

you can take a new wastegate signal after the intercooler, and there is no pressure drop.

there will be a pressure drop regardless.  the turbo will be working a bit harder to achieve the 10 psi, and therefore require more fuel to do so.  the only difference is that the motor will be able to burn the extra fuel to create the pressure, and also produce more power.

some intercoolers have high pressure drop, while others don't.  there are benefits to both.  some allow the air to 'linger' in the intercooler a bit longer, cooling it a bit more, for a denser charge.  you get a pressure drop, but you can burn more fuel.  not so great when you get heat soak though.  the high flow ones are good for high boost, and only cool when there is sufficient airflow.

i would personally favour a water intercooling system, using a thermostatic controller on the cooling pump to manage the system and keep it cool.  pressure drop is about 0.1 psi or less  :wink:

[ahto42]

i dont think that more fuel is used, because the wastegate is longer closed and the turbo will spin better with more gasses on the turbine plates

[Rabbit on Roids]

i dont think that more fuel is used, because the wastegate is longer closed and the turbo will spin better with more gasses on the turbine plates

im pretty sure he knows what hes talking about saying its gonna use more fuel to make the same boost, cause your gonna have to spin the turbo faster at 10 psi w/ an IC than you would have to with no IC. and you need more fuel to spin the turbo faster.

[gldgti]

you guys seem to be missing the point about the intercooler pressure drop, and what it actually does.

IF the intercooler setup is working well, its cooling hte intake air.... this makes a BIG difference to the engine output.... as such you have more power to spare most of the time, and you use less throttle for the same outcome.

put it this way - with and without the intercooler, my AAZ achieves about the same milage or better with IC. But i have much better torque right through the rev range, and slightly lower EGT's with the intercooler plumbed in.... so something is making it easier for air to get into the engine.... it also makes MORE boost, and produces LESS smoke with hte IC.

look at it like this - when the turbo spools up, its working against all the air its just pumped through, minus the air thats going into the engine. now, if you cool the air that its pumped through, the volume of the air on the cool side must decrease. a decrease in volume results in an easier job for the turbo to pump through what its pumping.... so the more you can cool your intake stream, the better (in ANY case). It is NEVER desirable to have a restrictive intercooler (one with a high pressure drop based on a large flow rate).

what is important to realise is that the design of an intercooler is always aimed at a specific function intended by the mfr..... IC's from turbo gasser cars are usually restrictive in the upper rev range (for a high boost diesel)..beacause the car's they are produced for cars make little boost and at intermittent times.... and being restrictive means that the air will purely be flowing FASTER through them.... hence the restriction. an IDEAL (theoretically) intercooler  reduces the flow speed to zero (by having an infinite volume), and hence has no pressure drop, and will cool to its maximum ability... ofcourse this is impossible, but hte moral is that the BIGGER the volume of the intercooler, the slower the air will move through it and as such be cooled more effectively, giving you more power.

a restrictive or small intercooler will definately not cool better, just because it is restrictive.

likewise, an intercooled system will not by its nature force some kind of increase in fuel usage. (a poorly executed one might)

and note that this is not taking into account other things such as heat soak/sinking ability, etc.

[88jetta350]

Awesome explanation. Very good info.