a really big intercooler in progress

[slimtastic]

hello all, ive started another stacked core intercooler for a turbo buick, but this one has all the "bells and whistles". hopefully we can get intake air temps right at ambient for a full quarter mile. the core size is 24" tall 25" wide 3.5" thick. ill update the thread when its complete with full weld pics.

i added a few holes right at the base of the 3"bend to facilitate flow to the lower two grids in the intercooler, as bend are typically higher pressure areas, the hope is that maximum efficiency will be present.

a main air splitter mocked up for install. the leading edge of the air spliter is airfloil shaped.

intercooler inlet pipe view

 

[Royal-T-Ltd]

cool, looks good.... wish i could Tig weld...... question - why not just notch the tubing that gets routed inside the end tank by the core?? i would think that would be less restriction then air going through the holes...... maybe

 

[disco stu]

Looks good. But I would finish boxing it in and trace the outline on the elbow where it goes in the end tank and cut the excess off the elbow..

 

[Chuck Leeper]

And I would cut the pipe off at the edge of the tank, and add a divider in the pipe to put 1/2 the flow to the far end, and turn the other 1/2 to the core next to the pipe....
IMO, hi velocity air across those holes is going to tend to keep going to the far end of the tank. No incentive for it to make a hard turn to 1 side...

 

[slimtastic]

And I would cut the pipe off at the edge of the tank, and add a divider in the pipe to put 1/2 the flow to the far end, and turn the other 1/2 to the core next to the pipe....
IMO, hi velocity air across those holes is going to tend to keep going to the far end of the tank. No incentive for it to make a hard turn to 1 side...

Looks good. But I would finish boxing it in and trace the outline on the elbow where it goes in the end tank and cut the excess off the elbow..

cool, looks good.... wish i could Tig weld...... question - why not just notch the tubing that gets routed inside the end tank by the core?? i would think that would be less restriction then air going through the holes...... maybe

well my train of thought is that i dont wanna fully remove that section of mandrel bend cause once i do that i loose the ability to control the "aim" of the high speed coming out of the 90" bend. and with a decently harsh bend creating a higher pressure section, im thinking that a few holes added could drop a few cfm to the bottom of the core... im not looking to run majority of airflow through the bottom, and im only trying to get a little airflow coverage to 2 core rows by doing it.

 

[ijames]

I think Chuck is on the right track here, you won't get much air at all into the lowest tubes so why even have them? Tack the inlet tank the way you are thinking, seal with some tape or RTV, and connect a leaf blower to the inlet and see where the air comes out the other side. Then cut the inlet off flush with the inside and repeat.

 

[Squid4life]

Wow, that is some beautiful work. Very impressive!

 

[Otto J]

you better reinforce the outer weld once you weld on the end tank caps.
After a while it WILL split the end tank at the weld.

 

[bison]

What is the cross sectional area of the rows of tubing where the air flows across the core?

 

[bison]

I think Chuck is on the right track here, you won't get much air at all into the lowest tubes so why even have them? Tack the inlet tank the way you are thinking, seal with some tape or RTV, and connect a leaf blower to the inlet and see where the air comes out the other side. Then cut the inlet off flush with the inside and repeat.

A leaf blower is not a good simulation unless you are testing at the same cfm the engine is going to be using. Otherwise your airflow data is not accurate. The area of the tubing and design of the core is more important. You are not going to have a major difference in pressure on the same side of the cooler from top to bottom. It will constantly equalize which is a great benefit when designing an intercooler. More cross sectional area will slow the air down and give it more time to cool off while reducing pressure drop from restriction.

 

[slimtastic]

I think Chuck is on the right track here, you won't get much air at all into the lowest tubes so why even have them? Tack the inlet tank the way you are thinking, seal with some tape or RTV, and connect a leaf blower to the inlet and see where the air comes out the other side. Then cut the inlet off flush with the inside and repeat.

well i cant just cut the last 2 cores off. that would ruin the presentation and make for a very ugly end result. in the meantime im still confident that when confronted with a 90' bend, air at speed will gain pressure at the bend point. therefor a few holes placed midway up a bend will have some kind of flow through them simply cause of the pressure buildup at the bend....air hates turns

Wow, that is some beautiful work. Very impressive!

thank you for the complements!

you better reinforce the outer weld once you weld on the end tank caps.
After a while it WILL split the end tank at the weld.

well im rolling end tanks and welding in another aluminum metal form over to connect the two triangular looking end tank blanks. the end result will be more of a rolled end tank wich by comparison souldnt need much nore reinforment

What is the cross sectional area of the rows of tubing where the air flows across the core?

im not sure if i understand what your asking. could you please elaborate sir

 

[slimtastic]

ill have a few pics of end tank progress in a few days, so far im liking what i see. hopfully it performs well

 

[coach]

Just tuning in and read most of thread. Food for thought. Years ago I was talking to Mike Moran who runs some incredibly high powered turbo cars. He was in the 1st stage of building a then wopping 2200HP single turbo motor for his new Trans Am ( this was probably 1997-98). He was talking intercoolers with some other guys and I was just kinda listening as I had a blower car and was not into turbos yet. I do recall him talking about the air movement and what he called "deadspots" due to the shape of most coolers. Well what he had in mind was to take the turbo outlet and make a collector of sorts and then divide it into 3 or 4 tubes of equal length. The headers would then be welded on to the side tanks with one tube blowing thru the cooler in equal amounts of 1/3's or 1/4's. Is this making sense??? On the other side a similar looking header with a collector running out and up into the throttle body or bodies, which ever. He was pretty sure this would allow the air to enter at equal speed and volume and leave the same way without leaving dead air not moving. So basically you end up with a cooler that looks like it has 2 shorty style headers on each side. Dont know if it were ever built, but sounds very well thought out. He was also mounting an electric fan on it with its own scoop for fresh air. I know not all this could be done under the hood of our cars, but the concept could be used.

Just sharing a bit of info.
Coach:biggrin:

 

[ijames]

I wasn't seriously proposing to cut off the bottom rows, just trying to make the point that getting air into them is hard but if you don't do it they just go to waste . I know a leaf blower isn't an ideal source but it is at least something to test with, to start to get a rough idea of air distribution on the inlet side before you make the final tanks. Once it is on the car you can put temperature probes halfway between inlet and outlet, at the top, middle, and bottom of the core, and see what your temperature profile looks like during a pass - that will tell what parts of the core are getting the most hot air and what parts aren't contributing much. Good luck with it.

 

[bison]

im not sure if i understand what your asking. could you please elaborate sir

The open area in square inches of all the tubing in the core that the air has to flow through as it moves across the core. The open area has to flow more cfm than the engine will ever use or it will cause a pressure drop as rpm rises even though it may appear as the intercooler is working very efficiently since it will show low outlet temps. Most seem to think that the turbo is what is moving air through the engine but thats not really the situation. The airflow is pretty much constant based on the cubes and rpm. On some engines where backpressure is very low the turbo can move a lot of extra air through the engine during overlap but this is unheard of on any of these class racing engines or hard running street engines. The way i look at is air flow and air pressure are two totally different things that have to be looked at as two different things when looking at engines potential. I see a lot of fancy stuff out there lately but it most of it is a waste imo and does nothing for performance and makes installation and accessibility a nightmare. I think your onto something really good here and cant wait to see the results. Id leave the bottom rows on there and test this intercooler on a high airflow turbo engine before you decide to cut them off. Air will find the lowest pressure area to flow through if it has to. One thing about the air to air route is that you can never have a lower charge air temp than ambient and to get better than 10-15 degrees over ambient may require so much core that the weight and size of the cooler becomes unrealistic. Ive been using cheap front mounts and only concerning myself with how much air flow engine is using although i had to estimate the airflow based on the number of rows and open area on them since i always use a shot of methanol to drop the temps to ambient or below. Ive also noticed that it takes only a a lot smaller amount of methanol to get the drop but the engine needs a lot more than whats required to just drop temps if you are looking to really make a lot of power.