Quote:
Originally Posted by IneedAZ
Seems more tuning is needed with the TQ values so low. Doesn't seem balanced on that test.
|
Only peak boost is noted on the power plot.
The Magnum DI features a Patent Pending Stage 2 housing, the boost pressure is lower on the TVS2650 everywhere below 4500, fairly equal until 5500 then is slightly greater at the top end. (See plot below)
As far as calibration - the 2300 and 2650 are both tuned to the most power (knock limit) that could be made on 91 octane pump with a completely stock fuel system, exhaust (including cats), and engine. The 2650 starts to bump the limit of the stock fuel system at 6200 RPM and drops just below 2000psi@7K.
IATs on this unit are fantastic, they are the highest at the start of the pull (normal because of the lack of airflow through the SC at idle) and drop throughout the duration of the pull ending at 102F (pull starts with temp at 112F and ambient temp is 77F. Again this is a completely stock Z06 cooling system.
The impressive part is how much more power it makes with the same amount of fuel, we know from testing that it is without doubt the most efficient automotive SC ever manufactured, but I honestly never thought I'd be able to reach nearly the same power level (-15HP) on 91 pump gas alone that I was running with the 2300 on 91 + water/meth with the TVS2300.
So where does the extra power come from? Improved supercharger and intercooler efficiency along with developed port to port airflow and temperature distribution. This allows the engine to make maximum power using all 8 cylinders and ability to run more ignition timing without having a single cylinder cause the limitation.
With the TVS 2300 I am running a peak of 19.5 degrees timing at 13 psi boost (knock limit).
With the TVS 2650 I am running a peak of 23 degrees timing at 16 psi boost (fuel system limit - if I had more fuel I'd raise boost further)
So where does it go from here? Since I was already on the dyno and my 50/50 water-meth system is still installed, I turned the meth back on, dropped pulley the size by 5mm, and made a pull - I was kindly rewarded with 818 RWHP again at the fuel limit. Since I'm sorely limited by the stock fuel system, my next mods will be a low pressure pump and possibly a mild camshaft with the big fuel pump lobe. But for this week I'm focused on helping my son install a Magnum DI on his 2018 Camaro SS (LT1), really looking forward to see how the units works on that engine.
