dadasracecar
Member
Well today was the long awaited tuning session for my car post HPFpump install. Jordan and I were tuning so I only paid for dyno time. Pucker factor of ~8 for that... Anyway, the results were somewhat disappointing as I made ~270hp/290tq to the wheels. The cursed lean spot down low gave us trouble from the beginning. Between 2.5K and 2.8K we just couldn't seem to get rid of this lean hump that was pushing my afr above 13. My goal for the tune was 18 psi, and 12:1 afr and we pretty much hit it. It seems this car just doesn't perform that well in the cold. The temps at start were in the 40s and warmed to about 50 by the time we were done. This should actually produce higher than normal values but for the MZR DISI engine, it seems temps below 50 are not ideal.
As for the pumps performance, i'm pleased to report that we did have better control down low in the aforementioned region. If you look at the dyno, I've plotted the zeroed out 18 psi baseline, the 18 psi Extreme tune that was done with the stock pump, and today's final tune at 18 psi. You can see that the oscillation is much less severe with the new pump and stays in a much safer boundary. After that the plots are nearly identical save for the fact that my tune today was a little richer and so I lost some power and torque.
Looking at the datalog of today's run you can see that the the fuel pressure seems to stay right where it wants to be and the injector pulse width is normal. I was expecting to see reduced fuel pressure or longer IPWs in the low rpm lean region but that just doesn't seem to be the case. The injector duty cycle is very smooth and is only around 60 % (you have to multiply the number by two for a DI engine).
THe car pulls timing until it gets past the lean spot thankfully. Once there though, ignition timing is continually advancing to almost 14 deg advanced which tells me I'm not knocking and everything on the top end is going well.
This pretty much supports what cp-e has been saying that you don't really need the pump unless you're going to upgrade the turbo or do something really special. I've got a full bolt on car and I plan to continue to try and get more out of it (read cp-e turbo upgrade... c'mon guys!). With my setup I'm seeing a benefit from it in that I'm not as lean as before in the very low rpms. I don't have the turbo yet to really make use of it. yet.
One final thing. We did a pull at 19 psi and the results are below. It was largely negligible and so we backed it back down to 18. I guess I hit the efficiency limit of my turbo with that...
As for the pumps performance, i'm pleased to report that we did have better control down low in the aforementioned region. If you look at the dyno, I've plotted the zeroed out 18 psi baseline, the 18 psi Extreme tune that was done with the stock pump, and today's final tune at 18 psi. You can see that the oscillation is much less severe with the new pump and stays in a much safer boundary. After that the plots are nearly identical save for the fact that my tune today was a little richer and so I lost some power and torque.
Looking at the datalog of today's run you can see that the the fuel pressure seems to stay right where it wants to be and the injector pulse width is normal. I was expecting to see reduced fuel pressure or longer IPWs in the low rpm lean region but that just doesn't seem to be the case. The injector duty cycle is very smooth and is only around 60 % (you have to multiply the number by two for a DI engine).
THe car pulls timing until it gets past the lean spot thankfully. Once there though, ignition timing is continually advancing to almost 14 deg advanced which tells me I'm not knocking and everything on the top end is going well.
This pretty much supports what cp-e has been saying that you don't really need the pump unless you're going to upgrade the turbo or do something really special. I've got a full bolt on car and I plan to continue to try and get more out of it (read cp-e turbo upgrade... c'mon guys!). With my setup I'm seeing a benefit from it in that I'm not as lean as before in the very low rpms. I don't have the turbo yet to really make use of it. yet.
One final thing. We did a pull at 19 psi and the results are below. It was largely negligible and so we backed it back down to 18. I guess I hit the efficiency limit of my turbo with that...
