Intercooler Thread

[pianoman]

OK,

I have seen many questions regarding intercoolers, as I have some of my own. Mainly I would like people to answer that have spent time using many diffrent types of coolers. Both dsm's and also on diffrent cars. People argue all the time about bar and plate vs. tube and fin. One cools better but doesn't flow as well and one flows better but doesn cool as well. But which is better? What about size? Some people have huge front mounts on small turbo's and vice versa. What about cfm flow of a turbo in relation to the cfm flow of a intercooler? What about top to bottom as opposed to side to side? Is there that much diffrence in cooling power of an IC with the dimensions of L 12xH 7xW 2.5 as oppsed to L 12xH 8xW 2.5? How is an air to water IC bad for street use. For the size to cooling ratio, they seem so much better. When using it for a street application, does the water not get cool enough when running it though the water-cooler to justify it's use? Is there a general rule of thumb to go as far as HP to size? Example for an ic to support 400hp it would have to be at least 12x6x2.5? or for 500hp it would have to be 13x7x3.......? If I was going to purchase a turbo that flows 720cfm at 15psi and I needed to upgrade my IC would I want one the flows 800cfm? Or could I use one the flows 750cfm??

Lets assume that pump gas will be used since most people I know do not drive around on race gas. I realize that cars are diffrent and some knock more then others, But im trying to get some sort of ballpark info. Also if you could post some numbers in relation to 16g, big16g, evo16g, 20g(tdo6), 50trim, 57trim, 60trim, and 60-1. Or if it would be eaiser: 30lbs/min., 35lbs/min., 40lbs/min., 45lbs/min., 50lbs/min., 55lbs/min., 60+lbs/min.



If theres any bases I haven't covered then just put it in your post(s).

Pianoman.

 

[1993eclipseGS]

I dont really know any of your questions, Being there are so many of them! But, I have a tube/fin fmic and it isnt even a 3" core, I've had my boost at 20psi already with 0 knock at all. So i'm assuming I could have went more. Not bad for 200 for the core and 30 something on piping. It's my first fmic though, It seems to do it's job so i'm happy.

 

[pianoman]

can you post your IC dimensions, along with the turbo your running.

 

[1993eclipseGS]

i think my intercooler is 20x8x2 or something, I'm not really sure i forget. Now, I just ordered a to4b, But when i was tuning , I had a big 16g and i was at 20psi with 0 knock, with more left to go.

 

[sweet97]

I have the Dejon street FMIC. Bar & plate. 15.5" x 7" x 3". Did not have to remove or hack bumper. I have a 50 trim turbo and it's only capable of 15 psi though with more tuning it could probably do 18 PSI but still not enough for the 50 trim. I may go back to the EVO 16G. That is probably the max for the IC I have, a big 16G. Mark

 

[1993eclipseGS]

Do you get knock at anything over 15psi? did you notice a big diff. with your 50 trim compared to the 16g?

Anyways - I hadto cut my bumper all up and remove my bumper support, If that matters.

 

[sweet97]

Yes, I just can't seem to tue it any higher, even have some knock now but it stays at 20 degrees advanced timing wise. I got a great deal on the 50 trim and it spools quick but tay should run t least 18 psi, ideally 20+ to get out of it what I should. I also did not want to cut the bumper as it sounded qite extensive. The car is very pristine for it's age! mark

 

[Slipstream]

People argue all the time about bar and plate vs. tube and fin. One cools better but doesn't flow as well and one flows better but doesn cool as well. But which is better?

What about size? Some people have huge front mounts on small turbo's and vice versa. What about cfm flow of a turbo in relation to the cfm flow of a intercooler?

What about top to bottom as opposed to side to side?

Okay, I snipped down the questions to those I can answer based on my knowledge and experience.

bar and plate vs tube and fin. Absolutely correct, b&p typically flows better, but t&f cools better. Though some will argue one is the end all be all of the intercooled world and the other is complete crap, the truth is that neither is "better" if you can flow 10kcfm through your ic but it doesn't get any colder than the intake charge what's the point really? Also if you can drop the intake temps by 50* but can only flow 1 cfm what's the point? The trick is to figure out the best compromise between flow and cooling for your specific application. Personally I prefer a larger bar and plate design so that there is enough surface area to cool the air, but still maintain good flow characteristics.

Yes you want to choose your intercooler relative to the flow volume of your turbo at the given psi you intend to run.

Top to bottom vs side to side isn't much of an issue. It doesn't really matter (to a noticeable degree) to the air. Some people prefer a certain style based on the way they want to layout their ic piping.

In the end it comes down to choosing an ic with a flow rate relative to your turbo. IMO the larger the better because the larger it is, the more surface area it has, the more opportunity to cool the air. However you reach a point of diminishing returns from a performance standpoint, a feasibility standpoint, and a financial standpoint.

I may be mistaken but it seems like you're looking for the bleeding edge best IC for you, (nothing wrong with that) but it also becomes a matter of to what level you wish to disect ic theory, and reality (not here but elsewhere I've watched a debate on reflectivity index of the ic, size of the ic, and angle of the sun relative to the surface of the IC as it travels down the track; span for 2 years and involved some rather complex physics calculations with never a "final" answer..and all for what? half a degree cooler air if you only drive west before 11am on thursdays while wearing a blue hat?

Is a .5" thicker core going to be any better for your application? will that .5" make a noticeable difference? are you pushing the car hard enough on the ragged edge where that .5" means just enough cooler air to prevent destroying the motor? only you can answer those kinds of questions. This is all relative to your goals, intent and so forth. For most of the applications I've seen an upgraded side mount is more than suitable, but a fmic never hurts. I'm not trying to be a jerk or nitpick you, your application or the topic, I'm just trying to gain some insight into where you intend to go so that I (and others) can give you a better idea of where you need to go with an ic and to what extent it will make a difference of x core over y core.

 

[eclipse90gsxt]

I have a Slow Boy Racing FMIC, which is a huge core. The core is 24x12x3.5, and just installing that lowered my cars temp 10 degres. I usually had 205 be the normal temp, but after this instal they fell to around 195 or so on normal driving. Also I did have a GT-12 also from Slow Boy racing, which is a .56 trim.

I did have a smaller Spearco core before which was a top to bottom flow instead of side to side like my SBR core. The spearco core was 12x12x3 and it did its job when I had a Big16G a few years ago. I didn't see the temp loss like with the SBR core, but I ran 15 on the street and 20+ at the strip and knock was minimal if any. Here are some pics to show you the difference.


-Patrick

Spearco Core..

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New SBR FMIC

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[guitarXgeek]

Okay, I have a quick question about front mounts as well. The SBR 2g FMIC is 24"x12"x3.5" while the spearco 2-216 is 28"x10"x3.5" (these are the two I have been leaning towards the most). I plan on buying it at the same time as the to4b(~49lbs/min) that I will be purchasing/mostly pump gas.

I realize that each IC is specific to the application, but I'm just curious as the advantages of having the spearco which is 4" longer, but 2" shorter up/down?? Both are bar/plate. I'm leaning more towards the SBR since it's 4" shorter in length, which means less trimming and moving shit (correct me if I'm wrong). Does more width have any advantages/disadvantages over more length?

I don't mean to hijack the thread, but I think this question will also help out anyone else that's as curious as I

 

[talon96tsi]

i think many would argue that to fully utalize a 12" core, you would have to cut your bumper cover so the air hits it directly. personally, id rather have a wider core, so that the air hits more of the surface of the core, without having to cut my bumper cover to hell, but you also have a 2g, and i have a 1g

my .02$

 

[Maglin]

i think many would argue that to fully utalize a 12" core, you would have to cut your bumper cover so the air hits it directly. personally, id rather have a wider core, so that the air hits more of the surface of the core, without having to cut my bumper cover to hell, but you also have a 2g, and i have a 1g

my .02$

As far as having to cut the Bumper cover goes... You can get the Drift style bumper cover. It has a larger "hole" for your IC.. It's cheap and isn't all stylish which is something I really like. It just gives you that JDM look of the S13 kind of.. The SBR FMIC is a good deal for it's price compaired to other kits out their. They use Garret Cores which are very efficent for B&P IC's. I'm poor after my engine build up so I'm going to use a 12x24x3.5 tube and Fin IC until I can save up another $950 for the SBR kit.

About actual size of the IC.. If you are just started out modding your car you may only way 300-350 WHP and a smaller IC will provide for you. But the chances of you wanting more and going with a bigger turbo that will require a larger IC is very probable. I unfortunatly just had to cancel my FP3065 purchase due to other life issues so I'm stuck with the B16G until I get my 20G together...

 

[pianoman]

Slipstream,

No offense was taken at all, nor did you come off as a jerk. Like I said, I guess im trying for lack of better words, get some ballpark info. Although does the angle of an ic have any more or less cooling effect? Instead of having it directly up and down, what about if its angled either foward or backward? There are so many options for ic's out there. So i guess im trying to get maby, some application specfic answers. Look at the bottom of my first post. I hope this makes sense as im having some trouble trying to type what I want to say.

Gutiarxgeek,
(I realize that each IC is specific to the application, but I'm just curious as the advantages of having the spearco which is 4" longer, but 2" shorter up/down?? Both are bar/plate. I'm leaning more towards the SBR since it's 4" shorter in length, which means less trimming and moving shit (correct me if I'm wrong). Does more width have any advantages/disadvantages over more length?)


That was one of the questions I had in my first post. But I think I deleted it on accident when I had edited my post. Thanks for asking it.


Pianoman

 

[sweet97]

www.dejontool.com has their race FMIC on sale for $599. It's a Bar & Plate, 28" x 10.5" x 3". They are also offering $50. off the pipes when you buy both the upper and lower. Most of the IC's for these cars are not angled. Just not much room, therefore the cutting or replacing of bumpers for large IC's. Hey Patrick in Rochester are you referring to coolant temps?? 205* to 195*? I also agree with having the core itself filling in the space/shape of the opening. I saw one pic where the guy cut into the top section of the bumper to expose more of the IC. mark

 

[sweet97]

Well it's priced in line with SBR, RRE and Extreme PSI. The option was the small frontmount I got from Dejon which will not handle the 50 trim. I ca't believe the Johnny Race Car $200. IC is priced as it is and does what is claimed!! What is their exact web address? mark

 

[sweet97]

Thanks! Just seems to be....amazing! I'll check it out. Did you keep the bumper intact, just cut the radiator support? Great.

 

[telly699]

I really don’t pretend that I am an expert by any means, but...

Lets discuss pressure drop. There are two MAIN factors in intercooler design to consider, correct? Cooling efficiency, and pressure drop.

Pressure drop causes a lot of problems if your intercooler is losing 3 or 4 psi. Your boost gauge is reading 18psi (depending where you have it tapped - i.e. at manifold) but your turbo is actually pushing 21psi because of the 3psi loss at the intercooler, causing more heat in general and additional wear on the turbo... less power - more wear.

Anyway, in the book, "maximum boost" it is stated that an intercooler with vertical fins will provide constantly less pressure drop than one with horizontal fins because the air has less distance to travel travel in the open between end tanks. It makes sense, but then why are nearly 99% of intercooler models on the market vertical finned? Are the gains simply negatable?

Do any manufacturers offer hard numbers in regards to efficiency and pressure drop?

Any comments on the subject. Me and my friend have been looking into this for a while now.

-Jerad

 

[telly699]

pic

 

[Endz0r]

bar and plate vs tube and fin.

what about extruded tube?

 

[pboglio]

Pianoman,

I agree with a few of the posters. Keep it simple, don't over-analyze. Of all of the research I did on these boards I never got the expected results that other people did. Mods that gave other people huge gains gave me small gains. You have to test out your own parts without relying on other peoples impressions. Having said that, in my opinion large intercoolers should be used with the intent of reducing octane requirement under mega boost, enlarging your fuel and timing window and reducing intake pressure drop to reduce your turbine backpressure. NOT for huge horsepower gains from reduced intake temps alone.

Buy the biggest side-side I.C. you can afford that doesn't completely block your radiator core with the shortest pipe routing. The I.C. pipe diameter I don't think is all that important after doing a few rough major & minor pipe loss calcs. The I.C. core looks like the bulk of the pressure drop. Smooth design end tanks would also be nice.

I was "extremely" disappointed when I first installed my Intercooler and went out for a drive. I was expecting huge torque increases from everything I read. When I changed my line of thinking and used the I.C. to run high boost pressures and lean the hell out of the car with a lot more timing advance thats when I saw gains. Now I'm happy with my ADFX 23"x10"x2.75" side to side extruded core intercooler. Lag increase was maybe 200 rpm or so, well worth it. Big reduction in knock counts. I'm running a FPt28/28 on 22 psi and getting around 319 w.h.p. or so. I worry more about my manifold/turbine backpressure causing reversion and knock than I do about knock induced from intake temps. I would have went bigger but I bought my I.C. before the big 28"x12"x3" cores became popular. With the kind of questions you are posting you won't be satisfied unless you gather your own pre&post I.C. temps & pressure readings.

If you are into "over-analyzing" I would recommend one of Spearco's old catalogs which includes very detailed pressure drop and heat exchanger efficiency curves for every I.C. core they sell. As well as actual on vehicle FMIC testing results. Spearco's "All About Intercooling" is another good source. John B. Heywood's "Internal Combustion Engine Fundamentals" is the bible for engine design and testing. Desktop Dynos "Using Computers to Build and Test Engines" completely explains the theory of intake/exhaust pipe resonant tuning. Any Fluid dynamics text will allow you to calculate your own major and minor pressure drops in pipes. A Fluids or Thermodynamics text should also allow you to determine compressor and turbine work values. Any college level Heat Exchanger text will give you a huge resource for cross flow heat exchanger theory and data. Autospeed.com has an article that "completely" takes the mystery out of head porting. Best magazine article I ever read. Cheers.

 

[Slipstream]

what about extruded tube?

Unfortuneately I don't have any personal experience using, testing, or playing with an extruded tube design so any input on my part would be conjecture and hearsay. Though I have heard of impressive things from them.

 

[Slipstream]

Do you actually have the equipment to read both inlet and outlet temps?

Sidenote:
Even though it's a bit extreme for most applications I'd love to get the equipment together for benchtesting all the various intercoolers on the market. A mock up front bumper and variable speed industrial fans to simulate airflow across them at various speeds, the ability to feed the ic's various temperatures, volumes and pressures to the inlet, and monitoring outlet volume, pressure and temperature...too bad there isn't a 3rd party testing lab for performance auto parts (similar to consumer reports for common goods) that could isolate and test specifc variables on the equipment. Though individual results will always vary (real world versus bench world) it would certainly shed some light on the multitude of equipment available, especially intercoolers.
/sidenote

 

[pianoman]

I unfortunetly don't have the money to run my own ic tests, which is why I have posted this thread. But thats why I was looking for people that have actully delt with ic's. So that way I could get some type of real world responses. I defintly will look into those books that you recommend. Im always up for some good reading, more so if it has to do with performance aspects of cars. Thanks.

Are the JRC ic's a extruded tube and fin?

 

[theNEW]

Ok, I have a question. I know it might seem a bit silly, but I need to know for appearance reasons.

I have a 95 gst with the stock bumper and will be upgrading in 2 months to the newer style bumper.

What are the dimensions to the mouth of the stock 98/99 bumper. Height and length??

Thanks,
Gilbert

 

[Slipstream]

I'd settle for the temp sensor where you stick a probe before and after the intercooler and you have a digital read out. I can't remember the name of it or where to find it (I know that doesn't help ) but it ran a couple hundred bucks. I'll try and track it down, it's in an old post somewhere... maybe one of you guys have seen it and have it bookmarked?

Sounds like common scientific equipment to me, available from any lab/science supplier

cheaper versions like this may be helpful
http://www.professionalequipment.com/xq/ASP/ProductID.663/id.22/subID.174/qx/default.htm