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Hey Guys,

We all know how well the Perrin Big MAF works :lol:

There is another solution. The Cobb Legacy SF Intake, as it is ~69mm vs. the stock 65mm. It has not been formally released as of yet, but they will sell it to the STi customers needing a larger MAF solution. The Legacy SF intake makes MAF calibrations a breeze and is very consistent from run to run.

If you want to get one, call Parker @ Cobb and let him know you want an SF intake for your STi, but want the Legacy intake for a larger diameter MAF solution.

*WARNING* You WILL need to have the car tuned for this intake otherwise you will run dangerously lean. There are no ifs, ands, or buts...you MUST have a MAF calibration tuned for this intake.
 

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What is Cobb asking for this?

What is everyones thoughts on blow through?

Thinking of doing that or SD on my Utec.
 

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I've got one at home and I am excited to install it. Its a *really* well thought out peice of equipment... made out of heat resistant polymer and with flow conditioning vanes too.
Im not sure what the headroom is on the 70mm, but it should at least deal with my 3" green and ~400 awhp :)
 

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I currently have a blow-through, and it was in NO way straightforward. Boost pressure does interesting things to the MAF curve, and even with a ton of nice aluminum honeycomb doing flow conditioning and the best possible placement, I still get turbulence at high flow levels, making the AFRs hard to keep steady.
 

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On my Red/Meth, this same type of intake ran out of MAF voltage WAY too early. I made mine out of the tube inside of the Legacy GT air box. This will be nice for smaller turbos or cars not running meth. Scott Siegel has mine, maybe he will post a picture of the one I made.
I got another LGT air box and cut the flow straightener section of the pipe out and put it in the end of my Perrin big MAF and it is as steady and smooth as ever as far as the MAF readings go. And I still have the MAF voltage head room needed for my high boost set up.;) Scott might possibly be able to post a picture of this one as well.
 

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VSGTS14 said:
since i'm tuned on the big maf, if i swapped pieces would it affect anything? or would i have to be retuned?
Yep, your intake calibration will be totally off.
The last line of STirish's post says it all.;)
 

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Great info! My local shop (that has done many utec tunes) had good luck with a blow through on a GT35R setup. But the more I read, the more speed density looks appealing. I just don't to be the test pig.

JDM-STI- You using the FPRed 7cm correct? Awesome HP/TQ! Can't wait till I get mine in.
 

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rodent said:
Great info! My local shop (that has done many utec tunes) had good luck with a blow through on a GT35R setup. But the more I read, the more speed density looks appealing. I just don't to be the test pig.

JDM-STI- You using the FPRed 7cm correct? Awesome HP/TQ! Can't wait till I get mine in.
Yep! 7cm hot side. Absolutley love my set up. We are going for 500 whp very soon.;)
My car makes 30psi pretty easily and can hold it just about to redline. And this is IWG with a catted DP. Just haven't been able to push it that far on the dyno yet. But will soon.:)
 

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JDM-STI said:
Yep! 7cm hot side. Absolutley love my set up. We are going for 500 whp very soon.;)
My car makes 30psi pretty easily and can hold it just about to redline. And this is IWG with a catted DP. Just haven't been able to push it that far on the dyno yet. But will soon.:)
NICE! Keep us posted.
 

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Bump for information on whether anybody has actually installed a Legacy GT short ram on an STi. If so, did it bolt on easily or did you have to fabricate anything? Also any results?

Looks like RainMaker was going to do this, but I did not see any specific follow-up. Also looks like JDM-STi used the Legacy intake, but modified it in some way and I'd love to see pics of what he did.
 

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This is thread from the past!

Here's another option:

Spectre MAF tube that you can buy at Pep Boys for 15 bucks!

The Spectre MAF tube is 2.82" ID (71.62mm). You would need a proper tune for this.

Pic of my old setup using APS inlet and Spectre MAF:
http://home.comcast.net/~k5shawn/sti/maf.jpg
Used a flex tube that went down to a 3" filter. Just don't use Spectre 45 or 90 couplers since they neck down in the middle too much.
 

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I ended up sticking with the blow-through as an effort in tuning. In the end, I got everything tuned perfectly except the Tip-in, which is set up in the time domain all wrong for the blow-through. I will be moving to a TMIC from my FMIC shortly after changing from the 3" green to the FP-evo3-16g I have.

At that point I will temporarily run the stock intake in order to get everything aligned and tuned. After that I may try the APS 70mm, the Injen I already have, or something else. The problem with the Legacy SF Cobb is that its not a cold-air intake, and Im a big fan of that.

Chris
 

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Thanks RainMaker for the follow-up. Any idea on whether the Cobb Legacy intake would have actually fit? I may call Cobb and see if they actually put one on.

I would love to do the APS 70mm, but I'm afraid of running a CAI in the snow. I run my STi year long, including runs across frozen snow covered lakes.

As for the Spectre (Rodent), that is no doubt doable and a great value. ButI like the straightener in the Cobb unit, plus the fact that Cobb's is not metallic and won't conduct heat like the Spectre/Perrin.
 

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If I was going to do any air kind staightner I'd do a LS1/LT1 MAF screen like this one.
http://www.ncgweb.com/corvette/pics/MAF9.jpg


The Spectre MAF tube is plastic not metal. Just chrome plated co-polymer which is suppose to insulate and reflect heat.
 

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I have the Cobb intake and it is a piece of cake to tune. Only thing I don't know is if Cobb supplies a silicon hose to connect it to the inlet pipe or if they have changed the intake since I got mine (mine was a prototype). If it is identical, then you might have trouble finding a silicon hose to fit the end of the intake. The one that comes with the APS inlet will fit as that's what I use. The Perrin hose I had wouldn't fit over the end.
 

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Rodent;
Are these the parts you used?
Air sensor mount (8705)
4" straight (8708)
6" straight (8718)
Did you place the filter straight into the pipes? It does not look like there is enough space for a filter there? What are the dimensions of your filter?

I asked Shaun at the Spectre forum http://www.powerflowracing.com/forum_new/topic.asp?TOPIC_ID=108&whichpage=2&SearchTerms=turbo if the sensor mounts and pipes were safe to be used before the turbo and this is what he answered:

shaun USA 468 Posts
Posted - 10/19/2006 : 18:57:41
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our intake tubes are not designed for turbo applications. the aluminum tubes we are coming out with would be able to handle it. then you have two options that way you can either have them tig welded or you can use silicone couplers but untill them i would not recomend using our polymere tubes on a turbo application.
[/QUOTE

His answer doesn't make much sense to me given that the stock turbo inlet pipe is plastic.
Comments?
 

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marmun99 said:
Rodent;
Are these the parts you used?
Air sensor mount (8705)
4" straight (8708)
6" straight (8718)
Did you place the filter straight into the pipes? It does not look like there is enough space for a filter there? What are the dimensions of your filter?

I asked Shaun at the Spectre forum http://www.powerflowracing.com/forum_new/topic.asp?TOPIC_ID=108&whichpage=2&SearchTerms=turbo if the sensor mounts and pipes were safe to be used before the turbo and this is what he answered:

shaun USA 468 Posts
Posted - 10/19/2006 : 18:57:41
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our intake tubes are not designed for turbo applications. the aluminum tubes we are coming out with would be able to handle it. then you have two options that way you can either have them tig welded or you can use silicone couplers but untill them i would not recomend using our polymere tubes on a turbo application.
His answer doesn't make much sense to me given that the stock turbo inlet pipe is plastic.
Comments?
Yeah, those look like the parts I used. Never had problems with turbulence either. The flex hose went down to a filter and was located behind the fog light cover. I tried just the MAF tube with a 3" filter connected directly to it but seam to have more tubulence.

I'm doing blow through now so I don't need it.

Not sure why that guy is saying those parts aren't meant for turbo applications. Mine worked great. Now if you tried to use that as a blow through then I could see the plastic cracking if you put enough torque on the T-bolt clamps. But there's no reason why the Spectre MAF tube won't work. Stock STi and Legacy MAF tube is also plastic so I don't see a difference.
 
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