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Intercooler for stock turbo: lightest yet effective?

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#1
My build is very weight conscious for tracking and as a challenge I enjoy. Originally I wanted the DHM crash bar for the weight savings and then the race intercooler to keep temps down and support max power on the stock turbo. However, I now know that combination will still result in a net increase in weight.

What I am wondering is, which intercooler(s) on the market offer the lowest weight increase over the stock intercooler but yet are sufficient enough for the stock turbo to be maximized?

The plan would be to go with the DHM crash bar and an intercooler with a minimal weight increase over stock so that I still get a net decrease in weight off the nose of the car.
 


Siestarider

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#3
I went through this process several years ago and decided the Cobb was the best weight vs performance IC for my uses tracking a Cobb S3 tune.

May have to do it again, C39 will likely reward more IC weight with commensurately greater power. Probably either the Mishi J in garage now or DHM big one.

Really hate the weight though, it will have to use up all the Cobb has before I add weight.
 


OP
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Thread Starter #4
in case anyone is wondering, DHM race intercooler and crash beam adds 3lbs. over stock crash beam and stock intercooler.

http://www.fiestastforum.com/forum/...and-Intercooler!?p=71970&viewfull=1#post71970

I saw that and hence my concern. If I don't really need that huge of an intercooler for the stock turbo, I'd rather come out with a net weight loss than gain.


I went through this process several years ago and decided the Cobb was the best weight vs performance IC for my uses tracking a Cobb S3 tune.

May have to do it again, C39 will likely reward more IC weight with commensurately greater power. Probably either the Mishi J in garage now or DHM big one.

Really hate the weight though, it will have to use up all the Cobb has before I add weight.
Any idea what the weight gain was with the Cobb vs stock?

I can only assume there is probably a linear relationship between the intercooler efficiency and intercooler weight. Question is what is the best compromise...
 


BronxBomber

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#6
You are literally talking about a very negligible difference. Why sacrifice cooling which is in essence ability to make power, for a measly 2 or 3lbs which will mean nothing noticeable when it comes to performance/handling. One thing you should not skimp on is cooling on this car. The FMIC is one of the most important parts on our cars for making reliable power whether staying with the stock turbo on a stock tune, or going balls out big turbo. My weight fluctuates by 3 lbs in a week. Now granted my weight is not directly over the nose of the car, but I think you get my point. If you're worried about weight, get a Braille carbon fiber battery. It weighs 11lbs less than the stock battery. I am going to go with the DHM Race Intercooler and Crash bar because of the cooling capacity on charge air temps.When the turbo is pushing out high boost those charge air temps rise dramatically. I did a data log 3rd gear pull and my charge air temps went up 21 degrees at night while running the CobbFMIC. This is just my opinion.
 


OP
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Thread Starter #7
You are literally talking about a very negligible difference. Why sacrifice cooling which is in essence ability to make power, for a measly 2 or 3lbs which will mean nothing noticeable when it comes to performance/handling. One thing you should not skimp on is cooling on this car. The FMIC is one of the most important parts on our cars for making reliable power whether staying with the stock turbo on a stock tune, or going balls out big turbo. My weight fluctuates by 3 lbs in a week. Now granted my weight is not directly over the nose of the car, but I think you get my point. If you're worried about weight, get a Braille carbon fiber battery. It weighs 11lbs less than the stock battery. I am going to go with the DHM Race Intercooler and Crash bar because of the cooling capacity on charge air temps.When the turbo is pushing out high boost those charge air temps rise dramatically. I did a data log 3rd gear pull and my charge air temps went up 21 degrees at night while running the CobbFMIC. This is just my opinion.
I know, I know. But I have a weight goal to look after and I've explored all of the options with a small list left to tap into. I can't even put the stock power down at the track so I am only concerned about making reasonable and reliable gains on the stock turbo.

I have a battery weighing in at 5lbs, so I've already tapped into that.

The intercooler is positioned nearly as far forward on the car as possible, as is the bumper beam. So this is a great place to lose weight but if you do that with the crash bar and then add the biggest/heaviest intercooler possible, you have not only undone that gain but then added a few more pounds.

Another way of putting it is that I don't need extra headroom as I don't intend to go beyond the stock turbo and a pro tune.
 


BronxBomber

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#8
I've been contemplating notching the stock crashbar. This will likely shave a few pounds and allow a bit more air to the radiator
 


OP
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Thread Starter #9
I've been contemplating notching the stock crashbar. This will likely shave a few pounds and allow a bit more air to the radiator
Not a bad idea. Maybe box it back in for strength and then grind off the back of the grill for the airflow and then run a smaller upgraded intercooler with stock mounting.
 


TUX15ST

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#10
Im not sure if this would even be option as far as fitment but what about a stock focus st or rs intercooler? Bigger than the fist one and still significantly lighter than any other aftermarket ic because the plastic tanks
 


OP
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Thread Starter #11
Im not sure if this would even be option as far as fitment but what about a stock focus st or rs intercooler? Bigger than the fist one and still significantly lighter than any other aftermarket ic because the plastic tanks
Looks like I can pick one up for $75-100 used. Might be interesting to get one and compare the two. But if I can find the dimensions for both intercoolers online, that would save me the trouble.

EDIT:

Looks like the Focus ST intercooler core is 26"x6.35"x2.5" (412.75 cubic inches)

Fiesta ST is 710, 135, 50mm 27.95"x5.31"x1.96" (290.90 cubic inches)

--------------------

So the Focus ST intercooler has 41.88% more core volume.

--------------------


Cobb Fiesta ST is advertised at 55% larger than OEM.
 


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#12
don't bother with the FoST intercooler. I got one for free to try and put it on the FiST. It is much shorter than ours and that added with the position of the inlet and outlet on the end tanks it makes it nearly impossible to connect without some serious rerouting.
 


TUX15ST

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#13
Looks like I can pick one up for $75-100 used. Might be interesting to get one and compare the two. But if I can find the dimensions for both intercoolers online, that would save me the trouble.

EDIT:

Looks like the Focus ST intercooler core is 26"x6.35"x2.5" (412.75 cubic inches)

Fiesta ST is 710, 135, 50mm 27.95"x5.31"x1.96" (290.90 cubic inches)

So the Focus ST intercooler has 70.4% more core volume.

The Cobb FMIC for the FiST offers a 55% larger core.

That would mean the Focus ST intercooler offers noticeably more volume than the Cobb upgrade.

I know that isn't all to the story but that might be worth a shot.
Stock FiST IC
Core Dimensions:
27.5" x 5.25" x 2"
Approx. 5lbs
Core Volume:
288.75 in

Stock FoST IC
Core Dimensions:
26" x 6.25" x 2.5"
Core Volume:
406.25 in
33.8129% difference over OEM FiST IC

Cobb IC
Core Dimensions:
27.5" x 6" x 3"
Approx. 13lbs
Core Volume:
495 in
52.6316% difference over OEM FiST IC
 


OP
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Thread Starter #14
don't bother with the FoST intercooler. I got one for free to try and put it on the FiST. It is much shorter than ours and that added with the position of the inlet and outlet on the end tanks it makes it nearly impossible to connect without some serious rerouting.
Ah, thanks. It did seem a little shorter. You have saved me some heartburn here.

Stock FiST IC
Core Dimensions:
27.5" x 5.25" x 2"
Approx. 5lbs
Core Volume:
288.75 in

Stock FoST IC
Core Dimensions:
26" x 6.25" x 2.5"
Core Volume:
406.25 in
33.8129% difference over OEM FiST IC

Cobb IC
Core Dimensions:
27.5" x 6" x 3"
Approx. 13lbs
Core Volume:
495 in
52.6316% difference over OEM FiST IC
I fudged my math earlier but edited the post.
 


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#15
yeah it is almost 2" shorter. If the inlet and outlets were facing out rather than facing toward the rear it would work. I am not saying that it wouldn't work, but the money spent to get it to "maybe" fit you could buy a j-line.
 


TUX15ST

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#16
Might be worth it in his case though, since he is looking for the lightest which the fost would definitely be at least 5lbs less than any other option
 


Siestarider

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#17
13 lbs sounds about right for Cobb, I recalled 12 lb, Mishji J around 20 lb, don't know Deadhook.

It all comes down to what you do with your car. On street I am sure Cobb will be fine for me with C39. On track, we know it will be heat challenged at higher rpm. On the other hand, it recovers quickly at speed, so its really a hp limit at the top end. If I get an honest 250 hp on 93 even with heat, I will probably stay where i am.
 


TempeST

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#18
FWIW, I wouldn't recommend the Mishi Jline. I would go for their new one with the little "gurny flaps" if you choose mishi. It is a better intercooler for the FiST. In my opinion if you are solely looking for weight drop. I would bet the FoST would be the best option, even with fitment issues it would be the lightest, not to mention if you are considering the Jline which also has fitment issues, why would you abandon the FoST intercooler for that reason but not the Jline?

For me, if weight was solely the purpose, I would go in this order, Stock FoST/FoRS, Levels, Mountune, Mishi FiST fitment FMIC(solely for the "gurny flaps that help direct the air into the intercooler itself.

Now this is completely opposite of what I would recommend all together. but if I were in your position, that is the direction I would take.
 


koozy

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#19
I saw that and hence my concern. If I don't really need that huge of an intercooler for the stock turbo, I'd rather come out with a net weight loss than gain.
The point is that most of the mainstream aftermarket intercoolers out there in combination with the stock bumper will net more weight that the DHM Race Intercooler/Bar combo.

The only way to achieve the least amount of weight will have to include the DHM crash bar. Severely hacked OE crash bars are not taken into account, but even then I think the DHM crash bar still takes the trophy.
 


OP
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Thread Starter #20
The point is that most of the mainstream aftermarket intercoolers out there in combination with the stock bumper will net more weight that the DHM Race Intercooler/Bar combo.

The only way to achieve the least amount of weight will have to include the DHM crash bar. Severely hacked OE crash bars are not taken into account, but even then I think the DHM crash bar still takes the trophy.
Oh yeah, that's the plan. Definitely want the DHM crash bar. Just want a lighter intercooler than the DHM race so as to net out with a worthwhile weight loss in the process.

I just realized that the Mountune and Peron intercoolers are both tube & fin construction. Supposedly half the weight of bar and plate. But there are downsides. And the Mountune is expensive...

Mishimoto's Fiesta ST specific intercooler is tube and fin as well and weighs 13.4 lbs.

Stock intercooler according to DHM is 6 lbs.

DHM crash bar saves 12 lbs.

So Mishi + DHM crash bar would be $1000+ for bettering intercooler but only 5 pounds net weight loss.

Seems to me like keeping the stock crash bar and going with the Mishi or a similar sized intercooler is going to be the only way to go and just deal with 7-10 lbs weight gain.
 




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