Quote:
Originally Posted by pgfpro
I hate to discredit anyone when it comes to making something better. I really hope that this company's claims are real.
IMHO I believe that any engine can improve on performance and FE when you run a turbo charger with a manditory programmable engine management system. I have seen this with the cars I have tuned and others that have been tuned by someone else first hand.
Now in this case as far as their HP claims I have no problem believing in their HP numbers. Major HP gains with turbos are being done all the time. With the turbos their running and the Corvette engine this should be pretty easy. The changes I would make...throw away the FMU and install larger injectors. FMU's are a cheap way to flow more fuel and are very hard on the injectors themselves.
Now as for the mpg claims I can see that its possible but my question is why aren't they getting a better freeway number when they are getting a extremely good city number? This part really confuses me???
The city part of the fuel and ignition maps are by far the hardest to tune for performance and FE. The freeway part is the easiest to tune. So one would think their freeway mileage would be a lot better then what they advertise?
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They're driving in the city at under 2400 RPM. The highway (and performance) tuning takes place at a higher RPM range, so no point in tuning below that.
They're able to claim increased efficiency (as with any turbo setup) because the mix runs slightly lean below the tuned point.
These are assumptions, of course. I have no idea how/if they tested.
One commonly forgotten thing about turbos is that they're ALWAYS working, as long as your foot is on the throttle. Just because you're not showing positive boost doesn't mean the turbocharger isn't doing anything - its' still pumping air, just not enough volume to create pressure in the intake. The engine still doesn't have to work as hard to suck in air, though, since there is more of an atmosphere readily available at the throttle plate. This means that more air is getting in than would normally be sucked in under the engine's vacuum, and thus, less pumping losses. Better low-speed FE comes from 2 things - less load on the engine, and leaner AFR, usually. The latter isn't always true, when EFI systems are self-monitoring, but most times, noone tunes standalones that low, so they end up with a stock basemap with tuning on top of it, and run slightly lean at low speed/throttle angles.
By the way, I got the honker. Good Gods, man. That thing is massive.
