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An all-aluminum 15 fin SAAB 900 IC?

Or a 10 fin, plastic tanked SAAB 900 IC?

Any ideas? Thoughts?

The all aluminum, 15 channel one will be more durable and might have slightly better cooling capacity.

The plastic end tank, 10 channel one will flow much better but you will sacrafice a slight amount of cooling capacity.

They are rare but there is an all aluminum 10 channel made. It's a Euro Edition. This is what I want to eventually replace my 15 ch. one with. I've only ever saw one on ebay and it went for around $90 USD but I think it would be worth it.

And AFAIK the 10 channel is considered an upgrade over the 15 ch.

You can't answer the question "which is better" in the general case. Usually you have to trade flow for cooling, so it depends on the particular application. For example, sometimes a big pressure drop is okay if the turbo's pretty inefficient and you need to get the heat out.

What did the Saab SPGs use? They may've had a bigger intercooler than the regular turbo.

Steve

I wonder... I could probably get slightly better cooling by wrapping the plastic parts in heat-dissipating aluminum tape, no?

I wonder just how important the flow would be? The inlet and outlet of the IC is already larger than the turbo outlet, so would it make that big a difference?

Anyone know the CFM flow of the 15 and 10 channel IC's?

I'll probably swap them back and forth and see which one I like better.

vrg3 wrote:You can't answer the question "which is better" in the general case. Usually you have to trade flow for cooling, so it depends on the particular application. For example, sometimes a big pressure drop is okay if the turbo's pretty inefficient and you need to get the heat out.

So for my car, which would you say would be better? The 10 fin or the 15 fin at 10 psi?

You've obviously confused me for someone with helpful information.

I think you'd have to do actual tests on the intercoolers to determine which would work better. I have no idea which one I'd place bets on.

Well, good thing I have one of each to play around with then

I seem to have a unique part. Anyone heard of a plastic end tank 15 channel one? That's what I have. Also, everyone's talking about 2" intake and output pipe on theirs, mine has 2.25" ID piping.

Mines a 15 ch. with plastic end tanks too. They're very common. Mine also has 2.25" ID inlet and outlet. When referring to the 2" ID we're speaking of the compressor outlet to I/C inlet pipe.

Phil- I'm going to throw in my opinion that the 10 channel will be better at 10 psi. The cooling capacity won't be as much of a concern at those lower boost levels. You will benefit more from the extra flow. Just my .02

Realize that the "extra flow" manifests itself as lower pressure drop. So if you're talking about boost in the manifold, you have to keep in mind that 10 psi manifold pressure with the 10-channel intercooler means a lower pressure ratio (and so less heat) at the compressor than 10 psi manifold pressure with the 15-channel intercooler.

That's why I have no idea which would be better. =)

It should be easy enough to compare the intercoolers though. Just swap each one in and use the scantool to measure the airflow signal at a given boost and engine speed. The higher number means more cfm, right?

Good call Vikash. I still need to make that thing. Time has been my enemy lately. It seems that I have very little free time this past week.