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Old 09-09-2013, 06:58 PM   #26
KartRacer3
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sub'd for update's. In for dyno results and possible pricing.
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Old 09-09-2013, 08:22 PM   #27
RalliSport Racing
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Quote:
Originally Posted by KartRacer3 View Post
sub'd for update's. In for dyno results and possible pricing.
Well you have good timing because I just updated my website. Dyno results will have to wait a few months. I wouldn't expect any huge gains from these alone, but they are a must for anyone wanting to take full advantage of supporting mods such as cams, head work, etc.
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Old 09-09-2013, 08:27 PM   #28
gc822
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Verry nice work
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Old 09-09-2013, 09:26 PM   #29
KartRacer3
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Quote:
Originally Posted by RalliSport Racing View Post
Well you have good timing because I just updated my website. Dyno results will have to wait a few months. I wouldn't expect any huge gains from these alone, but they are a must for anyone wanting to take full advantage of supporting mods such as cams, head work, etc.
Just checked it out. These will definitely be on my list for christmas
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Old 09-10-2013, 08:11 AM   #30
Distant.Calling
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Quote:
Originally Posted by RalliSport Racing View Post

Well you have good timing because I just updated my website. Dyno results will have to wait a few months. I wouldn't expect any huge gains from these alone, but they are a must for anyone wanting to take full advantage of supporting mods such as cams, head work, etc.
I'm not that versed in engine work, but would such supporting mods increase the compression ratio?
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Old 09-13-2013, 09:13 AM   #31
AMCjavelin74
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Originally Posted by Distant.Calling View Post
I'm not that versed in engine work, but would such supporting mods increase the compression ratio?
To increase static compression, you can mill the cylinder heads and/or run thinner head gaskets. I'd go against using a domed piston since it's not very efficient for flame travel to have a combustion chamber shaped like an orange peel. I think that ideally a slight dish in the piston is preferred as it offers more "working" surface area for the combustion pressures to push against.

Bolt-on parts, such as intakes and exhaust, reduce pumping losses. You're not really making any more power, just freeing up power that was spent pumping air through a restrictive factory (designed to be cheap to make and easy to install during manufacture and quiet too) intake or exhaust system.

As for turbos, an engine running at 14.7psi or 1 bar basically doubles the displacement of the engine with the intake side of the engine operating under double atmospheric pressure. A 2 liter turbo engine at 14.7psi makes approximately the same power as a similar technology 4 liter naturally aspirated engine. I say "similar technology" since a fairly modern Subaru turbo engine will make more power than, say, a 4L (or 242 cubic inches) Jeep engine with roots tracing to 1964.
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Old 09-14-2013, 09:03 AM   #32
Distant.Calling
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Quote:
Originally Posted by AMCjavelin74 View Post

To increase static compression, you can mill the cylinder heads and/or run thinner head gaskets. I'd go against using a domed piston since it's not very efficient for flame travel to have a combustion chamber shaped like an orange peel. I think that ideally a slight dish in the piston is preferred as it offers more "working" surface area for the combustion pressures to push against.

Bolt-on parts, such as intakes and exhaust, reduce pumping losses. You're not really making any more power, just freeing up power that was spent pumping air through a restrictive factory (designed to be cheap to make and easy to install during manufacture and quiet too) intake or exhaust system.

As for turbos, an engine running at 14.7psi or 1 bar basically doubles the displacement of the engine with the intake side of the engine operating under double atmospheric pressure. A 2 liter turbo engine at 14.7psi makes approximately the same power as a similar technology 4 liter naturally aspirated engine. I say "similar technology" since a fairly modern Subaru turbo engine will make more power than, say, a 4L (or 242 cubic inches) Jeep engine with roots tracing to 1964.
Very interesting. Thanks for the response!
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Old 10-28-2013, 11:12 AM   #33
arthuruscg
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Wow, does it hang down lower then stock? I am also thinking about a skid plate.
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Old 12-21-2013, 12:57 AM   #34
RalliSport Racing
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Default Just in time for Christmas

I reacquired these from the original purchaser (who sold his Subie) about a month ago, so they have only about three months of use on them. They have the OEM grade high flow cat and I just had them ceramic coated in Cerma Krome. They are beautiful, in stock and ready to ship!

In the mean time before they sell, if anyone with a 06-11 2.5i near St. Paul MN would like to help me dyno test them, I and the community would be grateful.
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Old 12-21-2013, 01:27 PM   #35
Back Road Runner
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It'd be fun to test if I had a car that it could bolt to. I've dyno ran my old Forester a couple times and have done a ton of road logging as I modded it. Unfortunately it's using a very long, old TWE header that doesn't bolt up to the stock location.
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Old 12-22-2013, 08:47 PM   #36
MillercLean
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Those look great! Very jealous of those water cut flanges.
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