Intercooler question

[canadian]

I just have a few questions I couldn't find while searching.

Why is it better to have the in and out pipe on the same side and one at the top and one at the bottom? Compared to in and out on either side?

Also, does the size of intercoolers matter? For example, will a 24x12x3" intercooler cool better than a 20x12x3.5" ?

Also, what intercooler from Driftmotion will be best, allowing for future upgrades (it's stock, not for long though):

Spearco replica: http://store.driftmotion.com/productdetails.php?sid=1448e310b00001&product_id_int=287

OR

unknown driftmotion: http://store.driftmotion.com/productdetails.php?sid=1448e310b00001&product_id_int=272

Thanks

 

[DaemoN]

Someone correct my answers if i'm wrong, but

Why is it better to have the in and out pipe on the same side and one at the top and one at the bottom? Compared to in and out on either side?

I believe people recommend this because that is how the stock intercooler is setup so it would ultimately reduce your ic piping length. You don't want miles of piping for it unless you enjoy lag.

Also, does the size of intercoolers matter? For example, will a 24x12x3" intercooler cool better than a 20x12x3.5" ?

The issue here is you want to know more about the intercooler, the core is what is important. A larger intercooler with a bad core won't stand up to even a nice side mount. Unless you are lacking a stock ic or yours is dented, the stock intercooler is great for a stocker and will be fine till upwards of 450 horse (opinion).

 

[Nick M]

I suppose going straight across is best, but with the intercooler routing, you lose that benifit.

The factory intercooler leaves little to be desired with regards to both pressure drop and cooling effectiveness. When we ran our first dyno tests on the Supra (TURBO Jan '87) we thought the restriction at higher boost pressures was actually in the turbo, but in conferring with Cartech, Spearco and HKS it was found that the stock intercooler itself was a major contributor to the problem. Testing at Cartech showed the stock intercooler to have a 3 psi pressure drop a 6.8 psi and a whopping 4.3 psi pressure drop at 9 psi. In other words, the turbo had to do the same work and therefore, produce heat as if it was run at 13.3 pounds of boost, while the engine itself was only seeing 9 pounds of boost.


All of these intercoolers are similar in size except that the Spearco unit also employs slightly larger diameter tubing in some locations going to and from the intercooler.


The only intercooler we were able do to an actual before and after test with on our own car was one of the units from Cartech. At stock boost pressure we found an 11-horsepower gain between the stock and Cartech intercooler. While this gain was actually measured at the stock (8 psi w/exhaust) boost pressure, it should be noted that intercooler efficiencies are best tested in a real world or street environment with actual air flow across the core. Previous testing on the Cartech intercooler showed a 7/10 psi drop at 6.8 psi and 1.10 psi at 14 psi which basically agreed with our dyno runs. In addition to actual pressure drop, Cartech testing of the intercooler showed 89% efficiency vs. 68% on the factory unit. With the similarity in intercooler upgrades, it would be safe to say that any one of these would be an almost mandatory option if you are starting to go for serious boost.

Just some interesting reading. I found a page somewhere, don't remember where, the HKS also is much more efficent than stock. Which goes with out saying I suppose.

 

[canadian]

So the spearco replica would be easiest since it uses the stock IC pipe configuration? How much do I lose if I were to change the routing? Is it just harder to plumb in?

 

[Jspec7m88]

I had a friend that had right at 500 to the crank in his MKIII and bought I believe a GReddy FMIC...After 2 days, took it off and put the stock one on because he said it felt weaker.