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-   -   BEGI Manifold Compatible w/ Newer FM Manifolds? (https://www.miataturbo.net/diy-turbo-discussion-14/begi-manifold-compatible-w-newer-fm-manifolds-16094/)

kenzo42 01-23-2008 03:03 AM

BEGI Manifold Compatible w/ Newer FM Manifolds?
 
I have the newer direct pulse BEGI manifold with a SR20 T25. I am wondering if the BEGI manifold mounts the turbo in the EXACT same location as a FM manifold?

I am thinking of purchasing the silicone hot side intercooler tubing that FM sells. If it's not exact, I won't be able to modify it since it's silicone. = (

http://www.flyinmiata.com/turbos/ima...G_4002_300.jpg

Braineack 01-23-2008 08:46 AM

shouldn't be an issue.

Saml01 01-23-2008 09:39 AM

How much is it, now you got me wanting one too.

Braineack 01-23-2008 09:44 AM

just FWIW.


Intercooling & Interesting Twists


The point of this argument is: The heat that finds its way through the walls of the tubes to and from the intercooler greatly contributes to the overall effectiveness of the intercooler system. Taking full advantage of that benefit is a must for any designer.

Premise: Never insulate a compressor outlet tube.

Testing my own turbo has produced an interesting set of charge temperature numbers. This was particularly evident with respect to the temperature changes in the tube from the turbo to the intercooler. Rather than produce a bunch of equations, I’ll offer the data and suggest a couple conclusions. The conclusions are rather obvious and have design quality and experience implications way beyond the data presented here.

The basic layout of the system: The turbo is positioned in the same place we originated 15 years ago, just 3.5 inches out from the head and an inch above the port centerline, right between cylinders two and three. One major change is the discharge of the compressor is now downward and out into the wheel well area. The tube goes forward to the intercooler, through the long tube IC core with baffled inlet, then out the opposite side, turns aft and up into the throttle. Pretty straight forward, but clearly not well understood, as evidenced by other designs offered up in the market. This layout was chosen specifically for the purpose of shedding heat wherever possible. For this test, all tubes were made from mild steel.

While seemingly obvious, but obviously not well understood, is the need to let the compressor outlet tube discharge some of the heat from the compressed air exiting the turbo. There is a substantial amount of heat that can be removed from this tube before it gets to the intercooler. EVEN IF THE TUBE STAYS UNDER THE HOOD IT WILL LOSE HEAT, AS THE UNDERHOOD TEMPERATURE IS NOT AS HIGH AS THE TEMPERATURE INSIDE THE TUBE.

We have taken the compressor outlet tube into the ambient air stream as quickly as possible. Hence, downward from the turbo and out into the wheel well.

Repeat:
The design principle: First; The air charge temperature inside the compressor discharge tube is higher than the underhood temperature, and Second, the discharge tube must get quickly out into ambient air temp where it can shed even more heat.

Here is how we tested it:
Data: We measured temps from right at the compressor discharge and at the IC entry. This data was consistent over several days of runs. Forward speed was held to 60 mph in 4th gear by dragging the brake. Boost was 6 psi. Time under boost was held until temps stabilized.... about 20/25 seconds. Tough on brakes, but we needed good data. The tally is an average of 12 measurements, none of which varied more than 3 or 4 degrees.

NOTE: This is a measurement of the temperature drop through the turbo discharge tube only!

Ambient F 95/96 F
Turbo Exit F 189/191 F
Temp Rise F 94/96F
Intercooler Inlet F 169/172 F
Temp Drop F 19/22 F

This data clearly states that approximately 20F is removed from the system through the walls of the tube between the turbo and the intercooler. Cool, eh?

Keep in mind that this data represents only 6 psi boost. At 12 psi, the compressor discharge temps will be approximately 90F higher yet. If so, while assuming the “efficiency” of the tube will remain the same, then the simple tube from the compressor outlet to the intercooler will discharge approximately 40/45F. Downright newsworthy.

General underhood area temps at the compressor discharge were 112/118 F. Temps in the wheel well area were 97/101 F.

This data states three things absolutely clearly:
1. The temperature inside the compressor outlet when under virtually any boost is far higher than the surrounding areas, thus heat exits the tube through the walls.
2. Behavior of the tube: The temperature removed from the system by the compressor outlet tube alone was 19 to 22 degrees F. Approximately equal to the temperature gain accompanying 1.5 psi boost.
3. Temperature out of the Intercooler, is within 5 degrees F of ambient.

Conclusions #1:
Anyone insulating the Compressor Outlet tube is blowing in the wind. That means their concept of the heat flow is backwards. If done so, their “Quality of Design” is subject to serious question.

Conclusion #2:
The compressor outlet tube should be made from a material with a high heat transfer capability, such as aluminum. This is precisely why we introduced the “multi-material tube set” moons ago with just that, an aluminum compressor outlet tube. Perhaps a bit in excess of reason, and not of world shaking proportions, but a maximum effort system should have a compressor discharge tube made from silver. Now, wouldn't that be a hoot? Maybe expensive too...

Conclusion #3: Porsche will one day build either aluminum, copper or silver compressor outlet tubes, and when they do, we will once again be able to claim we plagiarized their design.

Summary: Regardless of where the turbo is located,
NEVER, NEVER (NEVER SQUARED??) INSULATE THE COMPRESSOR OUTLET TUBE.

What is considered insulating a tube?
Wrapping in in fabric or using a heat retaining tube like silicone turbo hose

One more reason why the BEGi “quality of design” is superior to ALL others.

Should any reader like to verify our data, I’ll lend our digital thermometer to anyone for a reasonable deposit. You must use our Intercooler, tube system and duplicate our test conditions.

jayc72 01-23-2008 11:22 AM

Despite what the above says, I'd be interested in how much the pipes cost as well.

kenzo42 01-23-2008 01:42 PM

I was quoted $103 for the hot side. Cold side consists of 2 tubes (long and short): ~$103 and ~$30. Total ~$240.

jayc72 01-23-2008 01:46 PM

Shit that's not too bad at all. What size of I/C?

kenzo42 01-23-2008 01:57 PM

I was hoping to use the Cxracing one. 18 x 12 x 3. I'm sure some modifications will need to be done to the silicone though. The FM intercooler looks quite a bit larger.

kenzo42 01-23-2008 02:00 PM

Man, after reading what Brain posted, I'm having second thoughts.

Braineack 01-23-2008 02:06 PM


Originally Posted by kenzo42 (Post 203595)
I was hoping to use the Cxracing one. 18 x 12 x 3. I'm sure some modifications will need to be done to the silicone though. The FM intercooler looks quite a bit larger.

betcha $10 it's the same exact intercooler FM uses.

jayc72 01-23-2008 03:49 PM


Originally Posted by kenzo42 (Post 203595)
I was hoping to use the Cxracing one. 18 x 12 x 3. I'm sure some modifications will need to be done to the silicone though. The FM intercooler looks quite a bit larger.

FM offers two different I/C, a big and a little. I'm going to get measurements from inlet to outlet, core doesn't tell you enough since the end tanks could be of different design.

I'd take what Corky wrote above with a BIG grain of salt. I think what he's testing is flawed, and honestly not terribly relevant in real life. He never tests both types of pipes under the same conditions. He tests the difference between the outlet of the turbo and the inlet of the I/C. Distance traveled could have as much to do with heat shed and the type of material the pipe is made from. But we wouldn't know that because he only shows data to prove his point.The bit of data that we REALLY care about is post i/c temps. I would really like to see the difference between his metal tube and something that insulates. I'm willing to bet that the big assed i/c most are using will eat up the potential couple of degree difference.

Corky isn't god, just another vendor. And like FM, Trackdog, Goodwin ... etc, he has an adgena. To sell product. I'm not saying that he's wrong, but I don't see the above as anything more than a criticism of FM's product.

Maybe my thinking is flawed.

jayc72 01-23-2008 03:51 PM


Originally Posted by Braineack (Post 203607)
betcha $10 it's the same exact intercooler FM uses.

I'm sure you are 100% correct. How many Chinese companies are building intercoolers? I wouldn't be surprised if the Godspeed rad and the china-cooler are made in the same plant.

I'm going to stencil FM on the front of my china-cooler, increase the value by eleventy-billion.

Braineack 01-23-2008 03:57 PM

the only point he was trying to make was that metal pipes shed heat. so by using his IC pipe vs. one that won't shed any heat would be smart.

cause all else being equal (80% efficient IC). 20° difference in delta could mean an outlet difference of something like 16° out of the intercooler, from a simple pipe alone.

will 16° at 6psi make a difference, not likely.

but +12psi would be something like a 32° difference.

it's just food for thought.

jayc72 01-23-2008 04:05 PM

He states this as a fact. Strongly tells people not to use an insulated pipe, but shows now actual data that would prove this.

If the I/C was 80% efficient (your number) 20* higher inlet couldn't translate to 16* on the outlet, unless something is bustified. Wouldn't it be more like 4*?

If I could buy FM's solution at near the cost of doing it DIY I know what I would buy. Even if that means slightly higher IAT. You know as well as anyone that this whole turbo business is a mess of compromises. Theory is just that until someone shows it to be true.

Anyway, I'm surprised their I/C piping isn't more expensive.

Jay


Originally Posted by Braineack (Post 203677)
the only point he was trying to make was that metal pipes shed heat. so by using his IC pipe vs. one that won't shed any heat would be smart.

cause all else being equal (80% efficient IC). 20° difference in delta could mean an outlet difference of something like 16° out of the intercooler, from a simple pipe alone.

will 16° at 6psi make a difference, not likely.

but +12psi would be something like a 32° difference.

it's just food for thought.


kenzo42 01-23-2008 04:11 PM

[QUOTE=jayc72;203664]FM offers two different I/C, a big and a little. I'm going to get measurements from inlet to outlet, core doesn't tell you enough since the end tanks could be of different design.
QUOTE]

I didn't realize there are 2 different intercoolers. Are there pics or dimensions anywhere? All they list are the core sizes on their webpage.

Braineack 01-23-2008 04:16 PM


Originally Posted by jayc72 (Post 203681)

If the I/C was 80% efficient (your number) 20* higher inlet couldn't translate to 16* on the outlet, unless something is bustified. Wouldn't it be more like 4*?

no.

Turbo Exit F 189/191 F
Intercooler Inlet F 169/172 F

if we assume the silicone insulates the charge, which it will. then:

189 *.8 = 151.2° post intercooler
169 * .8 = 135.2° post intercooler

151-135 = 16°



Originally Posted by jayc72 (Post 203681)
If I could buy FM's solution at near the cost of doing it DIY I know what I would buy. Even if that means slightly higher IAT. You know as well as anyone that this whole turbo business is a mess of compromises. Theory is just that until someone shows it to be true.

true, but you can always buy BEGi's or Stripes pipes as well :)

jayc72 01-23-2008 04:30 PM

Their big one is 24" and the smaller is 19". Not sure what those measurements are of, but the one pictured looks like my I/C. If they are core sizes then my I/C is right in the middle at about 21", with overall of 29"

http://www.cxracing.com/mm5/merchant...Category_Code=

FM talks about it here:
http://www.flyinmiata.com/index.php?...%20BLK%20GAUGE


$100 - a 24" wide intercooler to replace the standard 19" unit. This upgrade is not compatible with air conditioning, and it's also a larger intercooler than the FM II needs on a stock engine. But it looks great and offers a good upgrade potential down the road.

Braineack 01-23-2008 04:35 PM

I'm sure they are talking core....

my 18" overall IC has an 11" wider core :)

jayc72 01-23-2008 04:35 PM

I'm not running a Greddy kit, so Stripes' pipes wont work. And I didn't think he was selling them anymore. I'll build my own before buying them from BEGI.

Math has never been my strong skill :) I see what you are talking about now. However this still means jack shit with out knowing how the other pipes would perform.


Originally Posted by Braineack (Post 203696)
no.

Turbo Exit F 189/191 F
Intercooler Inlet F 169/172 F

if we assume the silicone insulates the charge, which it will. then:

189 *.8 = 151.2° post intercooler
169 * .8 = 135.2° post intercooler

151-135 = 16°




true, but you can always buy BEGi's or Stripes pipes as well :)


kenzo42 01-23-2008 04:37 PM


Originally Posted by Braineack (Post 203696)

true, but you can always buy BEGi's or Stripes pipes as well :)

Stripes does DIY intercooler piping too? I thought he only did Greddy? If so, sweet. I have another option!


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