vertical vs. horizontal FMIC fins???

[blcknspo0ln]

hey guys,
I'm about to purchase a spearco core from a seller on another forum. Only question I have is - is there any difference between the fins being in rows or columns? Does it effect pressure drop, etc? from the looks of the picture, do you guys think it will be a good buy?

20 x 11 x 3.5

thanks for answering my n00b question

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[blcknspo0ln]

oh, and is this a bar and plate FMIC?

here are some other pics he sent me

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[KFT0001]

Yes that's a bar and plate core, and I don't think there'll be any difference mounting it with the bars vertical or horizontal - the air will still contact it at the same angle either way.

 

[14.5 drift]

is 20 x 11 x 3.5 dimensions of the hole thing or just the core?

 

[14.5 drift]

also I think vertical is way less efficient as the air spends less than half the time traveling through the bars where the cooling effects take place, also distribution through the bars is probly not as good, turning direction a complete 180 is also bad for flow, all these things are minor and definatly dont make this a bad intercooler, and it is probly alot easier to install also, just imo I think the standard front mount's are better.

 

[92awddsm]

I think the larger end tanks on the vertical ic also increases pressur drop and spool time.

 

[blcknspo0ln]

inlet is 2" and outlet is 2.25"

I dont know what you mean by whole thing 14.5drift. 20 inches endtank to endtank and 11 inches top to bottom

 

[92awddsm]

So the core is about 20"x7", right? Is the core 3.5 or 3"?

 

[blcknspo0ln]

okay so here's the specs that the guy just told me

core:
20 x 6 x 3.5

endtank to endtank:
20 x 11 x 3.5

I think it's a good deal, what do you guys think?

 

[MustGoFaster020]

Go for it.

And Yes they are half as long, but there are twice as many (tubes for charge air) so it's moving half as fast.

 

[DJ23GSX]

These should give you a good idea to help make your decision

http://www.dsmtuners.com/forums/showthread.php?s=&threadid=36072
http://www.are.com.au/techtalk/intecoolersMR.htm

 

[blcknspo0ln]

great read

I"m definately going to jump on this and find a way to get some piping in there

 

[kpt4321]

There are a couple things to note here, I'll try to keep everything organized.

Given that you have the same volumetric flow, the air is going to spend about the same time in the intercooler regardless of whether or not it is a top to bottom flow, or a side to side flow. This is a guarantee.

Top to bottom will oftentimes have less pressure drop, for two main reasons. The first reason is that there is more cross-sectional flow area, which means it's less of a "bottleneck." The second reason, which is related to this, is the air moves slower. Slower moving air will have less of a problem with drag in the core than faster moving air.

If you had two cores of the same dimensions (or what really matters is, the same exposed frontal area and the same thickness, the actual width and height can change some) then the odds are that the top to bottom flow core will be more efficient at removing heat, and also will exhibit less pressure drop.

However, it's not that simple.

Think about what happens if you mount the biggest possible intercooler on your car; you have taken up all of the space avaliable in the front of the radiator. Since a side-to-side FMIC has smaller endtanks, it ends up with a larger overall core area, than a top-to-bottom FMIC would have.

In addition, at any size level, a top to bottom FMIC will block some airflow from reaching the radiator; for the same core sizes once again, it will tend to make the radiator less effective than a side-to-side would.

So the answer is that a top-to-bottom is more efficient on paper, but when you get into constraints with packaging and the system as a whole, it may not always be like that.

 

[kpt4321]

Now, for some comments on that particular intercooler:

My primary instinct is simply to say "don't buy it" and be done.

The core is great; the endtanks are somewhere between "no good" and "freaking terrible."

Want to know why? There are lots of reasons.

First of all, there should be horizontal baffle that extends about halfway across the FMIC, to encourage airflow to use the second half of the core. Without this, the air will have a tendenc to go through the rows closest to the inlet and outlet. As far as I can tell from that picture, there is no such divider.

Second of all, I feel like those endtanks are not small enough. They simply don't look high enough to, once again, encourage proper airflow disribution.

Last but not least, the flat square shape is no good.

It's definately better than stock, but it has a lot of shortcomings.

 

[DCJ98GST]

kpt, you made some good points but for $200 I think it is a steal!!

 

[blcknspo0ln]