aftermarket intercooler too small?
 

18x12x3 CX Racing Intercooler on ebay

275whp

Street Ripper. No circuit racing. NB miata with power steering and AC with 2 inch intercooler pipes. The reason I went with small intercooler and piping is because there isn't much room with the AC/power steering components.

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Yes it is to small for 275hp. People on here have been using that IC for nearly 15 years. Anything north of what a stock motor will take power wise is time to spend money on a real quality IC.

Vibrant 12800. Fitment will be difficult but you likely wont ever have to replace it.
same thing as the fab9 stage 1, and a fraction of the price.

It is a good IC, you just have to make sure you mount it further back from the mouth to allow airflow above it to the radiator.

Yes, heavy hitters on here have been suggesting and running it, which is why I bought it. I guess for 250-275whp it's too small :facepalm:...

So how much boost or HP will this intercooler be sufficient? :redx:..

wait, wouldn't air make it's way through the intercooler? and to the radiator?

I know it wouldn't be much. About half as much air would get through as opposed to running no intercooler

I'm sure fabricating or using the stock air dam thing helps keep air going straight back and not out on the sides or under the car. I might eventually fabricate some aluminum brackets to make sure all available air at the bumper makes it's way to the engine and not out.

I would venture to guess the air would be a little warmer -- and reducing flow by 50% is probably significant regardless

Think it has to do with flow, too. The intercooler is going to make things somewhat laminar exiting, and without enough room or motivation to "rise up" to the upper rows of the rad it won't. Plus, it's a big prewarmer as already mentioned.

yea I agree. So it seems like we all agree a larger intercooler could have negative impact on the radiator cooling... I guess it's just one of those things of choosing which battle to fight

Perhaps that's one thing about the small intercooler is it can get more air to the radiator without blocking the entire radiator

If radiator function is a concern, I presume you have plugged all the holes, and the only way air coming in the mouth can exit, is through the radiator?

Radiator function and keeping my coolant temps below 205 degrees is important to me :likecat: ... since I mostly drive casually on the street and just cruise. I probably won't do long boosting sessions or endurance sessions so I'm not sure if heat soak from the turbo and smaller intercooler will really be a big deal for me.

I'm assuming a bigger intercooler is mostly needed for those who do multiple roll races or do endurance racing. Yes, I plan on 275whp but it's just to have a little fun from time to time. I won't be going to the track, really

I'm pretty sure a 2nd, 3rd, and 4th gear pull every once in a while won't be too dangerous with a small intercooler BUT I could be wrong and that's why I made this post!

I think you missed my point. A larger intercooler mounted closer to the radiator will cool everything better than a smaller intercooler touching and completely closing the front mouth gap, like the fab9 does. Mostly because you cut off airflow to half of the rad when you mount it like fab9 does, unless you add something to kick air back up at the top of the rad, after the intercooler.

A good big ass intercooler will have ducting in the end tanks that effectively does the same thing, just inside the intercooler.

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I went ahead and mounted it up

It will work, just expect air temps to go up with the higher boost levels. You should start searching for threads about ducting.

Seems like its already been settled, but you definitely need to assess the fact that it's a "street car" equally on both sides. Having a bigger intercooler will block more airflow and cause a warmer ambient when passing thru the ac condenser and radiator, so that is definitely a concern like you said. However, if it is a "street car", and you won't be romping on it, then that shouldn't matter. In that case, a bigger intercooler would be fine since you won't experience the consequences of overheating.

It does seem like you are leaning towards not swapping the intercooler out though - probably because you already bought it - and that's fine, you just have to treat them both equally. A lot of the problems you brought up aren't problems if it's a street car. And for that same reason you dismissed some of the solutions because it was a street car too. If you're really aiming for 275whp and you plan on using that intercooler, that's a no go imo. You will have to raise boost levels even more to make up for the lack of intercooler you have when you could make the same hp on less boost with a better IC. That is inherently better, and again for a street car, protecting the engine in regards to knock is going to be a bigger issue rather than protecting it from overheating. A bigger intercooler just makes your turbo and engine not have to work as hard to put x amount of power out.

You also already have or will be getting an upgraded radiator right? There is no way a stock rad will handle any sort of boost on top of full accessories as I'm sure you know.

At this point I'm not sure if the coolant re-route is necessary or if a bigger/better radiator would be sufficient for my goals. I'm not going to do many pulls just a few every so often as a spirited cruiser. Thanks for the post ;) I'm really re-considering this intercooler and just buying a larger one some day (for some reason I thought smaller intercoolers would lessen lag as well) :crx:. Yes, I do plan to keep this intercooler for now...