Dyno Gain 2.5" to 3" exhaust
04-08-2006, 07:39 AM
#46
I gained 31 HP on the dyno going from 2.5 without cat to 3 inch without cat - turbo back. Vitesse stock stage 3 turbo.
The gain is dependant on the capacity of the rest of the entire system. The k26/6 does not have the capacity to use a larger diameter exhaust on a 951 engine.
The gain is dependant on the capacity of the rest of the entire system. The k26/6 does not have the capacity to use a larger diameter exhaust on a 951 engine.
04-08-2006, 09:58 AM
#48
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BTW – interesting to note that at the highest RPM there was no difference – clearly showing that the turbo efficiency is the key limiting element not the exhaust. Turning up the boost further will not change that until the K26/6 is replaced.
The cat replacement does make a noticeable difference, even the cheap mild steel ones work fine.
Chris White
The cat replacement does make a noticeable difference, even the cheap mild steel ones work fine.
Chris White
04-09-2006, 11:35 PM
#51
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Is it possible the difference would be larger on a MAF equipped car, since that intake flow limitation would be removed?
This is great information to have, though.
This is great information to have, though.
04-10-2006, 10:19 AM
#52
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After the instal, did you have to turn the boost down to get back to the same level as before?
If so how much?
So even if not a lot of hp/tq gain at same boost levels, if the turbo is working more effeciently, i.e. you saw 2,3,4 more psi at same boost settings, then that is a good thing.
If so how much?
So even if not a lot of hp/tq gain at same boost levels, if the turbo is working more effeciently, i.e. you saw 2,3,4 more psi at same boost settings, then that is a good thing.
04-10-2006, 11:11 AM
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boost went up by nearly 5psi...I'm not really sure, I had to let off, as when I saw 20psi I got scared.
Yeah turbo runs soo much more efficiently.
MAF + open exhaust = happy turbo
Yeah turbo runs soo much more efficiently.
MAF + open exhaust = happy turbo
04-10-2006, 04:55 PM
#54
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Originally Posted by toddk911
After the instal, did you have to turn the boost down to get back to the same level as before?
If so how much?
So even if not a lot of hp/tq gain at same boost levels, if the turbo is working more effeciently, i.e. you saw 2,3,4 more psi at same boost settings, then that is a good thing.
If so how much?
So even if not a lot of hp/tq gain at same boost levels, if the turbo is working more effeciently, i.e. you saw 2,3,4 more psi at same boost settings, then that is a good thing.
04-10-2006, 06:41 PM
#55
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3" exhaust upgrade
Just curious, which magnaflow muffler are you using? I have a Borla installed on my stock 2.5" system from the PO, and it is too quiet to hear the motor on track days with the windows down.
Thanks,
Dave
Thanks,
Dave
04-10-2006, 09:29 PM
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Originally Posted by special tool
I gained 31 HP on the dyno going from 2.5 without cat to 3 inch without cat - turbo back. Vitesse stock stage 3 turbo.
The gain is dependant on the capacity of the rest of the entire system. The k26/6 does not have the capacity to use a larger diameter exhaust on a 951 engine.
The gain is dependant on the capacity of the rest of the entire system. The k26/6 does not have the capacity to use a larger diameter exhaust on a 951 engine.
