Anyone's done an X51 Dyno before/after?
Just curious... if anyone's done an X51 Dyno before/after?
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Would love to see that also.
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Are you referring to X51 headers, X51 intake, X51 manifold or a complete X51 conversion?
Jason |
Originally Posted by JEllis
(Post 3119946)
Are you referring to X51 headers, X51 intake, X51 manifold or a complete X51 conversion?
Jason Mostly I am interested in the headers, then intake as those are the easiest ones to install. I have yet to see anyone do a proper before/after dyno, while there are a lot of headers or intakes installed! |
I would also like to see something other than the manufactures claims.
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Someone awhile back posted on a dynotest of his stock 997.1S with X51 and I believe it did close to 340rwhp, he then added 200cpi AWE cats and it made over 360rwhp. Sorry these numbers are off of the top of my head.
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360 rear wheel horsepower for a 997.1S with headers and catalytics is totally unrealistic. Given a power train loss factor of around 15%, 360 rwhp/(1-.15)=420+ at the crankshaft. With headers only, 340 rwhp corresponds to about 400 horsepower at the crank. Not believable. We wish you were correct.
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I think the 360 number is a factory x51 engine with 200cell cats.
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Originally Posted by MichaelL
(Post 3120531)
360 rear wheel horsepower for a 997.1S with headers and catalytics is totally unrealistic. Given a power train loss factor of around 15%, 360 rwhp/(1-.15)=420+ at the crankshaft. With headers only, 340 rwhp corresponds to about 400 horsepower at the crank. Not believable. We wish you were correct.
Dave |
Originally Posted by DCI
(Post 3120687)
I think the 360 number is a factory x51 engine with 200cell cats.
I just purchased a 997 s X51 and was wondering if adding sport cats (fabspeed or AWE) would add power? and noticeable? |
Originally Posted by redline C4s
(Post 3120734)
would love to know if there is any truth to these claims...
I just purchased a 997 s X51 and was wondering if adding sport cats (fabspeed or AWE) would add power? and noticeable? Dave |
lots written here on sport cats. consensus is that it's among the best mods you can do on a 997, given that the OEM cats are so restrictive (600 cell). i think the mod makes sense for you since you already have the improved airflow from the x51 -- the sport cats would open it up even further, removing a bottleneck. expect low teens hp for the sport cats, mostly in the upper rev range. is that noticeable? depends on how you drive and your sensitivity. imho, for $1600ish, i can't say it's worth it, unless improving sound is also a consideration (which it was for me)... the sport cats exhaust note will be noticeably louder (in a GREAT way)! i do my weekend drives in north jersey so if u ever want to check out mine, pm me.
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I dynoed 321 to the wheels on a stock 997.1 I also dynoed on two separate dynoes with the same results
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Originally Posted by KonaKai
(Post 3120751)
lots written here on sport cats. consensus is that it's among the best mods you can do on a 997, given that the OEM cats are so restrictive (600 cell). i think the mod makes sense for you since you already have the improved airflow from the x51 -- the sport cats would open it up even further, removing a bottleneck. expect low teens hp for the sport cats, mostly in the upper rev range. is that noticeable? depends on how you drive and your sensitivity. imho, for $1600ish, i can't say it's worth it, unless improving sound is also a consideration (which it was for me)... the sport cats exhaust note will be noticeably louder (in a GREAT way)! i do my weekend drives in north jersey so if u ever want to check out mine, pm me.
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Originally Posted by 911 Molar
(Post 3121116)
whats the deal with the ipd plenum ? Is it worth it.......... on the new DFI's 997.2 ?
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