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The front one is the BMW 745i unit. The back one is out of a Volvo, a 740 (well, a 7 something, I didn't look that close).

Dimensions of the BMW unit are 10.5" x 8.5" x2.5". Inlet is ~1.75", outlet is ~2".

Dimensions of the Volvo unit are 16.5" x 17.5 x 1.25". Inlet and outlet are ~2.375".

Looks to me Like Mr. Volvo Intercooler will cool better (more surface) and flow bettter. It should fit in front of the radiator with minimal hacking. For $25, it's worth a try.



[Edit by Velocewest on [TIME]1140227326[/TIME]]

Well just great, now that secret part source (old Turbo Volvo) is gone....but on second thought....

I do have a really good euro car yard about 40 miles away and tomorrow is Saturday and I do have a need for a large IC for an upcoming project...

Good find T...and thanks.

W

Are you going to attempt relocating the throttle body to the other side of the intake manifold? Piping will be interesting, keep us posted!

FYI, I ran the numbers . . . rough volumes for either intercooler are as follows:

BMW 10.5x8.5x2.5 = 223 cubes

Volvo 16.5*17.5*1.25 = 361 cubes

62% more volume, roughly. Should be a nice upgrade.

Jeremy

a few days ago i posted a fmic from a saab turbo. Looks pretty much like that volvo one. Someone told me they've put nearly 30 psi through a 900 turbo with the same intercooler. $40 shipped.

The 745i interccoler will flow much better and be more efficient for it's size. It has a 30% greater cross sectional area. The Volvo intercooler will make for nice eye candy but a rather large restriction. Your engine makes as much HP n/a as the Volvo did turbocharged.

Todd

Yep, those volvo ICs are junk, they scored the lowest on flow tests and the plastic endtanks crack and break. The 745i is a bar and plate design with good endtank design and good core size.... the much better IC choice.

What a minute, this is all of a sudden more interesting to me right now!!!!

Umm, with that Volvo IC, as long as the turbo can overcome the flow restrictions, can the bar/plate BMW IC really be a better IC given its size disadvantage? Umm, how would that be calculated? If there a known efficiency rating of bar/plate vs extruded tube? Iguess just a glance says stay with BMW, as it's enough for the job.

But, if the Volvo unit is junk, and breaks, your no where also, thats enough right there.

In thinking of this, I noticed that my Dinan is extruded bar type. I would imagine a different design with bar/plate can yeild better results, Mmmm.....

RussC


[Edit by russc on [TIME]1140304008[/TIME]]

[QUOTE="russc"]... as long as the turbo can overcome the flow restrictions...[/QUOTE]
"Overcoming" the added restriction takes the form of more boost loss across the intercooler, right? It seems to me that it would be hard to judge the tradeoff in more cooling vs. more restriction.

Restrictions in the intercooler will make the turbo work harder to "push" the air through the intercooler. This will impart more heat into the charge. At that point you'd better hope that your new intercooler is capable of removing the extra heat from the restriction plus more since it's supposed to be an upgrade.

Russ, I'm suprised you didn't realize your intercooler wasn't bar and plate sooner! There's extra power just waiting to be had right there, my friend!

Jeremy

[QUOTE="Jeremy"]Restrictions in the intercooler will make the turbo work harder to "push" the air through the intercooler. This will impart more heat into the charge. At that point you'd better hope that your new intercooler is capable of removing the extra heat from the restriction plus more since it's supposed to be an upgrade.

Russ, I'm suprised you didn't realize your intercooler wasn't bar and plate sooner! There's extra power just waiting to be had right there, my friend!

Jeremy[/QUOTE]

Ya, I know, but Ive been ignoring it, maybe it'll go away"

RussC

So, what do we think about this IC?

Big AA IC

With the same inlet/outlet size, that could go in the front dam nicely?

RussC

those endtakes look like bricks... there's better stuff out there than that...

[QUOTE="Tjn182"]those endtakes look like bricks... there's better stuff out there than that...[/QUOTE]

Got examples? I'd be interested to see what people consider to be good a/a intercooler design.

[QUOTE="Tjn182"]those endtakes look like bricks... there's better stuff out there than that...[/QUOTE]

Ya, but the their measured Presure Drop: 2-5psi at 35psi; 0.2-0.5psi at 15psi seems pretty good if you believe them. I agree that the end tank for the loop could be better. I guess you could have a rounded end tank made instead. Since the inlets are so small, I don't think you need a large tappered cone for the inlet or outlets.

RussC

[Edit by russc on [TIME]1140499187[/TIME]]

Their feedback is 100% on almost 350 sales, and the comments from buyers indicate the quality is good. Same-side inlet outlet certainly makes the plumbing cleaner.

[QUOTE="Velocewest"]Their feedback is 100% on almost 350 sales, and the comments from buyers indicate the quality is good. Same-side inlet outlet certainly makes the plumbing cleaner.[/QUOTE]

Yup,
I just need to see if a 12" x 3" can fit up front and keep A/C functionality. It'll be real close Im sure.

RussC

I measured it without the condenser. I'm planning of putting in a 22"x12"x3" intercooler. Should fit like a glove and take up the entire hole.

[QUOTE="Velocewest"]Got examples? I'd be interested to see what people consider to be good a/a intercooler design.[/QUOTE]

I'd say their numbers are "doctored". They say it flows 700cfm but, at what pressure? 2-5psi drop but, at what flow.
The tank design is poor with no smooth or tapered transitions from tube to tank. The most basic calculation puts their charge air face at 24in^2 or a rated flow of under 200cfm. Their claimed flow of 700cfm would require a charge air face of 82in^2 to maintain decent efficiency.

[QUOTE="Sweeney"]I'd say their numbers are "doctored". They say it flows 700cfm but, at what pressure? 2-5psi drop but, at what flow.
The tank design is poor with no smooth or tapered transitions from tube to tank. The most basic calculation puts their charge air face at 24in^2 or a rated flow of under 200cfm. Their claimed flow of 700cfm would require a charge air face of 82in^2 to maintain decent efficiency.[/QUOTE]

Thanks,
I was thinking some of the claims could be dubious. But, from what I can tell for my situation, it definatley better than what I have. Just going to bar/plate and getting it out of the engine bay is good for a guess of 5-10% better effiecency in my case.

Gosh, Ill have to get the max boost book out and look at that some more.

RussC

eBay

Here's a link to the IC i've had my eye on for a while. It should fit very snugly where the condenser is. There might be a little chop involved but nothing too drastic. (of course, I'm going to move my TB to the other side of the IM)

http://cgi.ebay.com/ebaymotors/Grand-Na ... 0375QQrdZ1
this is a good design, not that i would personally use that vendor but this offers the least pressure loss for a/a

Correct me if I'm wrong, but it looks like the main thing you guys are pointing out other than bar/plate core is tank design. You want to see tapered tanks, which in addition to reducing turbulence I assume promotes an even flow through the core.

You want good flow to the core, slightly turbulant in the core to get all the air in contact with the aluminum and then a smooth transition out of the core. You also need the incoming air to "see" a large enough face to allow good flow and residence time in the core for the heat transfer to take place. Maximum Boost has some basic calculations for sizing cores relative to cfm and power requirements.

Direction of flow through the core is also very important, that first one with the square tanks was also a split core, essentially it would be like a 4 foot long but small intercooler, all the charge air would have to squeeze through the 4"x6" core area open to it, and travel a long ways with a direction reversal before it gets out. Very restrictive, and inefficient because the further it goes the less of a cooling effect there is, less difference in temperature between charge air and cooling air. The majority of the cooling effect is going to take place before the charge even gets to the turn around point, the trip back is much doing way more restricting than cooling. The one with the tapered tanks that flows top to bottom is a much better design in both respects, more area to flow through and a shorter distance to flow.

right to Sweeney and DMN,
The book likes more passages the better. My concern with the that Mustang IC is the distribution of air through that IC. It seems to me that more air will flow throught the inlet area that the other side, effectively reducing IC size. W/o proper baffling, its design is flaw'd?

RussC

Hey Sweeney,
On the calcualtion you did, did you actually calculate the ICs internal flow area or just use the table in the Bell book? In looking at the table, I guess 700cfm comes to ~36sqin. divide by 0.45 gives 78sqin. Divide by 3in thick core is 26in core length.

RussC

The charge air face on that intercooler is 6x4 inches. 45% of that = 10.8sqin


[Edit by Sweeney on [TIME]1140805717[/TIME]]

[QUOTE="Sweeney"]The charge air face on that intercooler is 6x4 inches. 45% of that = 10.8sqin

[Edit by Sweeney on [TIME]1140805717[/TIME]][/QUOTE]

OK,
I think I got this now. you taking the core face to the inlet, thats 6x4=24sqin. Then you multiply by 45% because thats the area of the air tubes that the air actually flows in. Thats the "internal flow area". The Bell book is going the other direction, and that confused me. The 45% is just a rough estimate w/o actually having the core right in front of you and actually take measurements.

Anyway, for AA ICs, you need a large core to have decent flow area for 700cfm, at least 25" length to have any kind of decent efficiency, as you have pointed out.

Its clear now that an IC can actually flow more air than the rated, but efficiency goes down and pressure drop goes up.

Mmmm
RussC

So inspite of the good features of the stock BMW intercooler, it sounds like an IC that is longer and narrower but has the same flow capacity would actually cool better, because each air molecule will travel through the IC longer, allowing for more heat transfer to occur. Makes sense.

So what is the tradeoff in terms of overall intake length vs. the cooling advantage? To mount an IC in front of the radiator and use an end-to-end flow, the overall intake piping would be at least 5 feet longer.

[QUOTE="Velocewest"]So inspite of the good features of the stock BMW intercooler, it sounds like an IC that is longer and narrower but has the same flow capacity would actually cool better, because each air molecule will travel through the IC longer, allowing for more heat transfer to occur. Makes sense.

So what is the tradeoff in terms of overall intake length vs. the cooling advantage? To mount an IC in front of the radiator and use an end-to-end flow, the overall intake piping would be at least 5 feet longer.[/QUOTE]

The only downside to adding pipe length is lag and slightly more pressure drop.

RussC



[Edit by russc on [TIME]1140821987[/TIME]]