Thread: Intercoolers Brand Name/Ebay

^Nuff said. I would do the same.

I feel like I should say something here. There's a possibility for us to grow as a community. When I first saw these $100 intercoolers I felt that it was a great thing. For the longest time it felt like name-brand companies were fixing prices for a lot of performance items. I understand the need to bring in R&D money and all, but I recall $900 Spearco intercoolers as the norm, and that's just madness.

These cheap eBay intercoolers seemed to be of the correct design, material, and quality for use in serious cars. After having first-hand experience with them I can now say they not only seem to have these qualities, but they do.

I'm going to link to an article with stuff you need to know about intercoolers so we can have a decent discussion. Don't skip this link. It is mandatory reading for everyone. Once you get to the "Doing Things Differently" section you can stop (unless you want to keep reading).

Fusion Intercooler


Combine this notion of an air-to-air intercooler as a heat sink first, and a radiator second along with everything Corky Bell has to say about intercoolers and we can now start to understand what make a name-brand intercooler better than the eBay units (because there must be something behind the gains, if there are any).

I'll summarize what Corky Bell says here:

Given the same sized core, it's all in the end tank design and placement.
You want the end tanks on the ends of the core that will give you lots of short passages for the air to travel through instead of a few long passages.
If you can, put the outlets of the ends tanks in the middle.
If not, try to have the outlets on opposite passages (top and bottom instead of both on top)
If you can, try to have curved end tanks, not square ones.
If you can, have baffles inside large end tanks to help direct air flow. (I've never seen a company employ this.)

Aside from end tank design, there is a balance to be made with the amount of fins to place inside, and outside the air flow.
Too many fins inside the air passages and you loose air flow, too few fins and you won't cool the air much.
Too many fins outside and the outside air won't flow through the intercooler (and it will dissipate less heat), too few fins and the outside air will flow through the intercooler without dissipating much heat either.

Another area of design is the height between air passages and the height of the air passages. More distance between air passages increases fin surface area and thus quickens the cooling of the intercooler by outside air, yet lowers the number of (or height of the) air passages you can have, decreasing charge flow through the intercooler.

Next up is the design of the fins themselves. There is a "louvered" fin design which is basically a staggered fin which results in better cooling but less flow than traditional fins.


Now, here is the fin design/density of a typical eBay intercooler:





Source: Ebay

Here is the fin design/density of a very high end (FCP) core:





Source: FCP vs. Spearco core


There's also the plate ends to take into account. For most cores (including the high end) this is the design. This would be an improvement.


If you've made it this far, you might be asking "Well Ben, how would you build your ideal intercooler?" and the question is tough to answer. What type of driving do you do? Is it daily driving? Spirited daily driving? Some track time thrown in? Autocross? Endurance racing?

There are things we care about in our intercoolers. What is the temperature difference across it? What is the pressure drop across it? How long does it take to saturate? And at what temperature does it saturate?

You may not care about time to saturation or saturation temp in a drag race, but the endurance racer sure does.


If I were to set out and build my own ideal intercooler I'd want to take advantage of all of the known techniques for making it great. There's a lot of trade-offs though, and I'd have to pick a goal for my driving first. If I were trying to market an intercooler I'd have to make assumptions and I'd probably end up somewhere in the middle.

If the eBay intercoolers really are losing to the name-brand units at very high HP outputs, it's due to the pressure drop. The question is then, is the pressure drop due to the designer (copier?) making a compromise with fin design, or is it just poor design overall (tiny leaks, less-than-ideal transitions, etc.)? This is assuming there is a significant difference of which I'm still not convinced.

I feel I'm rambling, and I'm late for an engagement so I'll leave you with this for now:

ARE Cooling (Aluminium Radiators & Engineering P/L)

If you haven't had enough, read that link or at least look over the pics. He even has his own take on eBay (Chinese) intercoolers.

Check this out:

Intercooler CFD Testing - HybridZ

BenFenner: I wouldn't have expected anything less out of you. An informative point of view, backing up what you are trying to say with some good links!

Very interesting. And to anyone who is interested in learning more about some important parts of turbocharging, I do highly suggest Corky Bell's book "Maximum Boost", its got some great information. I believe there are actually pdf's online of the entire book...


Dudeman

Hey swiss, thanks for the link. A great example of end-tank baffles and some flow analysis to go with it. Those guys over at HybridZ seem very knowledgeable. I'll add that link to my post above.

There have been some good points on how brand name IC's are better quality and can yield better HP results, as well as increased price. But, with that being said. When we (the majority of our sr community) are turboing a car on a budget, whether it a small budget or moderate budget, IMO it is not worth the few hundred dollars extra you will spend for a brand name IC. Like was mentioned before, spending 600 on an IC doesn't make sense when you could spend $100 on one similar and spend the other $500 on a better downpie, better manifold, better injectors, better MAF, etc. There is a ratio of money spent and HP gained. The gain in HP from one IC to the other, is not worth the extra $500, UNLESS it is the best money spent to HP gained ratio available for your specific setup. This would be the case if you already have say, injectors, nice manifold, nice maf, nice engine management, nice DP etc. Other than that, in my eye's, it is a waste of money and for that reason, I have gone with an ebay IC. I still have room to upgrade my DP, manifold and probably a coupe other things.

So basically from my theory above, it just plain doesn't make sense to get a $600 IC without supporting mods, leaving an ebay IC as a bottleneck. You have to have a balanced system. It just wouldn't make sense to get a nice spearco IC if you have a stock DET with stock injectors and ECU.

Ok so what is wrong with this statement:

In a situation such as a stock sr20ve, boosting can be very tricky given the high compression aspect of the motor. A high quality intercooler will help to reduce intake temperature's and prevent knocking, and possibly pre-detonation in high stress environments (track, drag, roadracing..etc). Lets say 10lbs on a gt30, hypothetically running a better intercooler would give you a much larger margin of error. No? Would this not allow for more power, higher resulting boost given less pressure drop with the SAME if not lower boost pressure at the turbo and less heat in the intake charge because you do not need to compensate. This all becomes very relevant when dealing with a motor with higher compression and the potential to knock with a street setup.

This thread was NOT created to tell everyone they NEED a super functional intercooler was it? I believe it was started to try and let people who might not know, that there is better out there..and for SOME, it can be a great tool. Why not leave the choice up to the builders, now at least they have information they didn't before. Let me guess, you would rather save the $400 and put in low comp pistons in the ve right...yea should have guessed..ha Carry on gents...

Dudeman

anyone read the mike kojama(spelling) article in the turbo and high tech performance mag about ebay parts? I'll take a pic of the article, or find it online

Until i see some good comparisons on lower hp sr20 cars i am not so convinced they are all that bad. I personally know quite a few guys around here making good power and they havent had any problems with theirs. And these are on drift cars which spend more time at redline going sideways, with little to no air hitting the i/c straight on or at all for that matter.

I would like to see some comparissons on smaller whp set ups. Like the 200-350whp range. It seems everyone thats done any sort of testing on the ebay i/c's is running like 30-50psi of boost and making 500-700whp which is just a little bit out of most peoples goals or specific whp output.

I dont doubt you can get a decent amount of power from upgrading to a name brand i/c set up. But for the lower hp cars i dont know how much you would actually gain. Its tough to base everything off the research of the honda guys and the mitsubishi guys, because everyone is running completely different engine set ups, and the engines are all different internally as far as compression, displacement and bore and stroke. So an i/c that would work good for the sr20 at 15psi might not be the best on a 4g63 which is most likely running 10-30psi more boost than we are.

Just my .02

wouldnt more fin density, cause a larger pressure drop?