Intercooler sizing

I have been searching and found nothing here at GRM that really answer to the question. How do you size an inter-cooler to a motor? and is one IC core size/configuration better than another (assuming you are using the same type of core)

From the reading I have done to big can actually be a problem.

Is there a simple formula that you can plug in boost, engine size etc and get the optimal IC size, I am looking at a front mount unit for my 924 ssc project and I am rather limited on the actual size I can run. The biggest issue is that I can not use a stock 951 unit as the pre 85.5 944s and the 87 924s's have a completely different upper rad support and the sheet mental under the valance is very different as well making the fitment a real PITA. there for a front mount down lower will be the direction I am going as it will be a much easier installation and be easy concealed in front of the rad.

Now the problem. I was looking at the stock units for many cars and they are alot smaller than what I expected compared to the aftermarket units (look at the Supper Coup ones that are working with a 3.8L) However they are usually not boosted to the moon either.

I am looking at an after market unit with the following specs

Overall Size: 457 x 300 x 75 18" x 12" x 3" Core Size: 280 x 300 x 75 11" x 12" x 3"

Fitment would be good but is it a good size for a 2.5 L car?

I am also concerned that it is more of a square as opposed to the longer shorter but thicker units (similar to the one I have for the 951) Is this configuration more efficient?

Please learn me about inter coolers. Specifically how configuration effects efficiency (22"x4"x4"= 352 cubic inches) close to the stock 951 unit. Versus the unit I am looking at above (11"x12"x3"=396 cubic inches). The actual cooling area is not all that much different so will the configuration make a difference or is that negated by the air actually slowing down as it goes through the wider area there for able to dissipate more heat? OR is frontal area of the IC the more important part as the 951 unit only has about 88 square inches versus the other FMIC unit I am looking at that has 132 square inches? Will more exposed surface area equate to better cooling?

Then there is the whole motor size versus boost as it applies to IC size. Any specific formula or is this more of a available space to put the IC problem not an actual IC size.

how about the intercooler for the 924 turbo?

mad_machine wrote: how about the intercooler for the 924 turbo?

Lear me more of said intercooler!!!!

While it's possible to have a too-big intercooler, it's really tough to pull off on a street car. You can calculate how many cubic feet of air an engine pulls in during one second - it's rare for the air to take more than a tiny fraction of a second to go through the intercooler. Usually if you can mount it without obstructing your vision or reaching into other lanes, it's not too large.

Some general rules - longer tubes may (or may not) have more cooling, but shorter tubes always have less restriction, all else being equal. You'll also want to be sure the end tanks promote good flow - really thin ones can make it so you only get good air flow through the tubes near the hoses.

Three things about going big: weight, fitment and pressure drop. Take a look at how the OEM intercoolers are sized - the SRT-4 i/c is supposedly rated to 350 HP, but is pretty compact. I looked at this as an example when I sized mine - hopefully Dodge engineers are smarter and have better calculators (scientific ones., even!) than me.

SRT-4 intercooler dimensions : 24.5" W x 5.75" tall x 2.75" thick

MadScientistMatt wrote: While it's possible to have a too-big intercooler, it's really tough to pull off on a street car.

This. I wouldn't worry about going too big. Sounds like you already have limited space - just fit the biggest bar & plate style you can.