Hope I'm not boring y'all but here's another one from the outside. Sounds MAGNIFICENT if I do say so myself...
Technical Hydra Performance 135 Leichtbau State of the Art Thread
- Thread starter Hydra Performance
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A custom creation we made using bits of stock F82 M4, F87 M2 exhaust, and a Berk race E82 axleback for good measure. Its surprisingly not that loud, even when going uphill in 6th @ 2000-2500rpm, but sings soprano once you give it the beans.
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Looks great. 2.5 dual merged to 3.5 down to 3 with resonator back to the berk?
Dual 65mm merged to an oval 80mm for maximum ground clearance all the way back to the 3" Berk axleback, with a single 80mm resonator just before
A couple of quick soundbites for y'all, until the next video comes along next week hopefully!
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Strapped my car down to the dyno for the first time in many years to see what it'll do on the new setup. Dyno is a Dynocom 5000x which reads within a couple % of a typical US Dynojet. Typical FBO N54 car makes ~420whp there, and we recently did a "Stage 2" decatted & tuned 2015 AMG GTS which put down 557whp for reference.
Unfortunately, the boost curve wasn't as well dialed-in as it is on the street, so I ended up with later spool up, a midrange throttle closure & a boost drop up top due to the vastly different ramp rate. Entire dyno run lasted just 4s from 2600rpm to redline, and that's despite doing the run in 5th gear. Full boost comes in some 500rpm earlier on the street, nice to see the power keep on climbing to redline though.
Unfortunately, the boost curve wasn't as well dialed-in as it is on the street, so I ended up with later spool up, a midrange throttle closure & a boost drop up top due to the vastly different ramp rate. Entire dyno run lasted just 4s from 2600rpm to redline, and that's despite doing the run in 5th gear. Full boost comes in some 500rpm earlier on the street, nice to see the power keep on climbing to redline though.
whp, fuel used is 93oct pump + E25 mixed in. Plenty more left in it in terms of both timing & boost, but it's completely unusable as-is, let alone tunable...
