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      12-12-2013, 09:39 PM   #40
A418t81
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Drives: 991.2 GT3/997TT/18 Raptor
Join Date: May 2007
Location: Alabama

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2013 335is  [0.00]
Good lord there are some uninformed people in this thread!

First of all, a piggyback particularly ones like the JB4 and Procede add a TON of functionality that a flash simply cannot offer. Gauge hijacking is one of them and the feature that I could not live without. I don't want to add a gaudy boost gauge to my car to get an idea of what is going on regarding that. Flashes and piggybacks work best together. Also, piggybacks have NOTHING to do with N54s overheating on the track. BMW simply did not design the N54 cooling system with enough thermal headroom to handle the heat generated by them on the track. This happens whether modded or stock...obviously quicker modded since more power = more heat. The M3 has massive amounts more headroom with this in mind.

Next, the F8X will not run at 18 psi unless temps are very high, or you are at high altitude, or both. The ECU has an internal model and essentially knows how much power the engine is producing at any given time. They give it leeway to raise boost up to a max of 18 psi to maintain the rated power of 430 hp regardless of temps or altitude. I suspect most cars will run somewhere around 1 bar of boost (14-15 psi)...which even on the N54 with smaller turbos is good for M3 power ratings.

Additionally, 430 crank hp is nothing for a modern, direct injection 3L motor. This engine isn't anywhere near tapped out. The compressor wheels on the turbos are good for substantially more flow than the N54's which have no problem producing 450+ hp. I imagine the turbos will again be constrained on the hotsides, but nevertheless should be interesting how much power can be attained...certainly there will be large torque gains to be had.

I'm incredibly excited to pick mine up this summer. The wait makes it all that much more fun!
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18 RS3, APR Stage 2: 10.73@130
'09 997TT 6MT, FBO/Upgraded VTGs, 730 whp
'18 Raptor / '18 GT3 Touring
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