Hello all,
I was looking to get some thought process behind why companies design their intercoolers with large squared off end tanks. I understand that it is easier/cheaper to fabricate than going with a smooth cast design, but in my humble opinion (and with very little evidence) I think the designs are not good for power and intercooler efficiency.

Take for example this formula one design

The end tank is extremely small and very smooth design. I don't understand as much about the fin design, but if any intercooler builder would like to chime in on why no one makes an intercooler that utilizes an extremely small end tank I would love to hear it.

The closest design I can see is the HKS Type R intercooler, very smooth end tanks, not exactly small, but I would say smaller than the majority of intercooler companies.

The other area for improvement would be to offset inlet and outlet ports for the intercooler to offer a more even distribution of air flow, rather than straight through from one port to the next. Maybe some thoughts on that would be cool to, though it might not be an option on the Evo. Thanks for looking.
Dan

 

Here is a link that I found extremely useful http://www.dvdtfab.com/intercoolertestlab.pdf
Dan

 

I have wondered about the square endtanks myself. But what do I know, I own a buschur I/C with the inlet from behind

 

I think the main objective of the IC above is to maximize cooling and not flow. Also that has to be at least 80's technology since it's on an f1 car.

 

Ya, no Intercoolers on F1 cars for 20 years, 1988 was the last season that allowed them. I think a lot has changed since then in turbocharging technology

 

I agree with you that many things have changed since then, but if you look at a modern Le Mans turbo car, the intercooler is extremely similar (and at the time, they still where making in excess of 1500hp out of a 1.5 liter motor, 1980s or not, that is amazing). I just couldn't find a picture that represents the design as well as this particular photo.

Someone brought up a good point, having large end tanks increases the volume of the intake system, decreasing throttle response. It is the same as adding additional piping to your intake system. It won't hurt total power that much, but it can delay throttle response.

 

one thing you guys should note on the discussion of the intake system is that a plenum is effectively all the intake tract from the throttle body to the back of the valve. The F1 cars had to run TB's pre turbo. So the minimalized endtanks could have been for volume tuning as well...with a 1500hp 1.5L you don't worry too much on throttle response, as you have none

 

Cool stuff, I knew the F1 cars ran the TB pre turbo, can you explain why? Thanks.
Dan

 

the reason for the tb or inlet guide vanes aka IGV, was so when the throttle was closed on the engine, the igv also closed, so the turbo couldnt take in any air, allowing the turbo to free-wheel & minimize the ability for the turbo to slow down.....

with no igv, the turbo would take in air, loading up the area between the closed engine tb & compressor wheel of the turbo. when this area gets filled up, the turbo slows way down because there is no energy driving the exhaust side of the turbo with closed throttle blades = turbo lag.

igv, isv, etc. were also used in CART by Cosworth & Honda.

 

dang, this is giving me a headache! lmao.

 

That's the ticket.

I work at an intercooler manufacturer which I won't name and while there are several things that reflect the end tank design, first and foremost it is cost. It is factually much cheaper to build an aluminum sheetmetal endtank rather than a cast one unless it is for a general market, i.e. Ebay Universal FMIC and your going to make 1000's of them. The flow through the IC is not as dramatically affected by the end tank as you would think, and by dramatically, I mean the difference of a few ponies at the wheel at most if that. It could be optimized of course but for even a performance minded consumer a welded sheet metal end tank is good enough.

A smaller end tank or shorter intake tract would increase throttle response, a great deal in some cases, but for the average consumer, it just isn't needed.

/Brox

 

^^ When we were manufacturing intercoolers the the SRT-4, our customers demanded more flow/less pressure drop. They insisted that it was our cast tanks being too thick. All we did was changed the charge tube from 1/4" to 3/8" and decreased the FPI from 13 to 10. This substantially increased the flow. Charge temps went up a couple degrees but the gain in flow and decreased pressure drop still netted more power. The core is where the action is.

 

While I can see where you're going with that, I'm not sure it's the backing up of the pressure in the intake tract. Isn't that what a BOV is for? And if we're talking about a single TB before the turbo, there would be no where to back up to, so couldn't you run sans BOV? I think the benefits here would just be the lack of air between the throttle body and the turbo, allowing the turbo to work under low manifold pressure, and therefore less resistance. Makes you wonder why OEMs aren't doing it.

 

this is interesting! i have a whole new outlook and understanding on intercoolers

 

So I did some talking with the engineer at my shop today about cores and end tanks. He showed me a few end tanks they had made for the European market with drop down inlets and outlets for Porsche's and what not. He had some interesting designs which had been used on several Euro track cars with space restrictions for the in/out and they had very flat caps, similar to the one originally pictured. He did say that more likely than not though, the reason for the extremely small end tank design was space restriction rather than throttle response, unless the car is supercharged rather than turbo charged and then the throttle response would be affected.

/brox