Anti-Surge Housings offer any advantages on our cars?

That spinning thing that makes all of the cool noises. OE and Aftermarket.

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BoneIslandScooby
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Anti-Surge Housings offer any advantages on our cars?

Post by BoneIslandScooby »

Could anti-surge be of any use with the turbos typically used in our Legacys? Should I end that with an ies, instead of a ys? Questions to ponder. But seriously if I was installing a VF22 compressor / VF34 turbine hybrid, billet aluminum compressor wheel with extended tips, and ceramic coating on exhaust side, would anti surge porting be of any use? Would it hurt anything? Could it hinder power production, or might I only expect improvements in power from anti-surge? Cost is not a consideration, just whatever advantages it might offer in power, durability, and driveability. Thank you for any help you may offer.
James614
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Re: Anti-Surge Housings offer any advantages on our cars?

Post by James614 »

I believe since Legacy is a noun in reference to our cars, it would be "Legacy's" and not Legacies. Just like you would not refer to multiple people named Stacy as "Stacies".

But onto your question about anti-surge housings for our cars. My understanding is that they are a trade-off, and it's better not to have it if you don't need it. But I don't fully understand compressor surge or what the anti-surge housings achieve. But I do know it only seems to be an issue on boost level well beyond what any of Subaru's stock turbos are capable off.
93 Touring Wagon (EJ20G 5spd Swap) -- Finally back and running strong as ever!

05 Outback 2.5XT 5spd -- Now the wife can have her SUV and get in on the turbo Legacy goodness at the same time.
BoneIslandScooby
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Re: Anti-Surge Housings offer any advantages on our cars?

Post by BoneIslandScooby »

From what I understand, the anti-surge porting allows excess pressure in the compressor side that cannot be used by the engine, or cannot flow past a more restrictive exhaust housing to flow back into the intake tract rather than stall the compressor wheel. It sounds to me like it would allow the turbo to stay spooled during part throttle. I read that it helps low and mid-range torque more than anything, and it sounds to me like that would be consistent with what I wrote just above. The assumption I'm making is that the larger VF22 compressor side with the smaller P18 Exhaust housing of the VF34, along with the billet wheel and the anti-surge porting is going to give me a turbo with good peak power potential along with some smooth and quick spool. I think it will be great for autocross. You know how alot of people on this board complain about bucking or jerking during part throttle acceleration? This could be due to compressor surge, and this anti-surge porting is specifically created to prevent that. I guess I'll be the guinea pig. I'll let you all know how it goes. I'd appreciate any more opinions however. BTW, the anti-surge ports are supposed to increase compressor whine. This along with the trademark IHI VF turbo whine, and the new billet compressor wheel will probably have this car sounding like a big rig on acceleration. If anybody is familiar with the Wicked Wheel for turbodiesels, the compressor wheel is made by the same people.
BoneIslandScooby
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Re: Anti-Surge Housings offer any advantages on our cars?

Post by BoneIslandScooby »

Anybody else? Anybody with experience having a comparable turbo with and without anti-surge?
kleinkid
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Re: Anti-Surge Housings offer any advantages on our cars?

Post by kleinkid »

Is this the porting you are talking about?

http://gallery.legacycentral.org/v/Memb ... ewsIndex=1
BoneIslandScooby
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Re: Anti-Surge Housings offer any advantages on our cars?

Post by BoneIslandScooby »

This is the sort of porting I'm talking about.

https://encrypted-tbn2.gstatic.com/imag ... skUC-mNNIw
James614
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Re: Anti-Surge Housings offer any advantages on our cars?

Post by James614 »

You could be a pioneer here. I dont think anyone else has given much thought to compressor surge on our cars. On the popular builds here its certainly not an issue.
93 Touring Wagon (EJ20G 5spd Swap) -- Finally back and running strong as ever!

05 Outback 2.5XT 5spd -- Now the wife can have her SUV and get in on the turbo Legacy goodness at the same time.
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