Car I tuned in Austin came to San Antonio to hit the dyno Saturday so we could test VCT/MBT for the mountune v1 cam (piper roadfast cam), we only tune this cam, not the v2/v3 because we can't tune for the cam angles in cobb software.
I've done a few cars with v1/piper road fast cams now and the results have been great.
Limitations here are that we are running out of fuel on the xdi35/30% injectors at around 30 psi on E30 with a pretty conservative AFR curve.
These dyno runs were around 28 psi of boost, typically we need 32-34 psi on the GTX2860 to get those 390+ whp numbers. This is not a high reading dyno, this is one of the most accurate dyno's I've ever tuned on and our 21 GT made 423 whp baseline which is inline with everyone else.
The bad news:
The car developed a slight boost leak on the dyno and we couldn't go any higher than 28 psi even though it was making 30 psi in datalogs when remote tuning the car (wastegate/fueling maxed) 14 psi spring actuator.
The car broke both control arms 2 days before the dyno, the car would not stay straight on the rollers and I had to hold the wheel to prevent the car from coming off. Based on my experience and asking around it's believed that the alignment being very off and the control arms being broken robbed us of the car most likely making an additional 20 - 25 whp.
I've asked the customer to bring the car back to the dyno to re-test after the alignment is fixed and boost control is sorted.
I believe with a proper alignment and new control arms this car is making roughly 385 whp around 28-29 psi and 390-400 whp at 30 psi. I recommended a wmi kit for additional fueling as well as a stronger wastegate to get boost to 32-33 psi and I think this car would be in 420whp territory.
The power curve is very flat and boost tapers to 7000 because the wastegate is maxed out so on the 367 whp pull we are at 28.5 psi 5500-6000 and then 6500+ the car drops boost to 27 psi and wouldn't go any higher with the current boost control. If I could hold 28.5 psi to 7300 the powerband would be flat with the v1 cam.
There's a lot holding this car back, but I'm really impressed with the results and the power curve.
21 GT baseline + tune only 93 + tune only e85 (all stock 10 speed)
I've done a few cars with v1/piper road fast cams now and the results have been great.
Limitations here are that we are running out of fuel on the xdi35/30% injectors at around 30 psi on E30 with a pretty conservative AFR curve.
These dyno runs were around 28 psi of boost, typically we need 32-34 psi on the GTX2860 to get those 390+ whp numbers. This is not a high reading dyno, this is one of the most accurate dyno's I've ever tuned on and our 21 GT made 423 whp baseline which is inline with everyone else.
The bad news:
The car developed a slight boost leak on the dyno and we couldn't go any higher than 28 psi even though it was making 30 psi in datalogs when remote tuning the car (wastegate/fueling maxed) 14 psi spring actuator.
The car broke both control arms 2 days before the dyno, the car would not stay straight on the rollers and I had to hold the wheel to prevent the car from coming off. Based on my experience and asking around it's believed that the alignment being very off and the control arms being broken robbed us of the car most likely making an additional 20 - 25 whp.
I've asked the customer to bring the car back to the dyno to re-test after the alignment is fixed and boost control is sorted.
I believe with a proper alignment and new control arms this car is making roughly 385 whp around 28-29 psi and 390-400 whp at 30 psi. I recommended a wmi kit for additional fueling as well as a stronger wastegate to get boost to 32-33 psi and I think this car would be in 420whp territory.
The power curve is very flat and boost tapers to 7000 because the wastegate is maxed out so on the 367 whp pull we are at 28.5 psi 5500-6000 and then 6500+ the car drops boost to 27 psi and wouldn't go any higher with the current boost control. If I could hold 28.5 psi to 7300 the powerband would be flat with the v1 cam.
There's a lot holding this car back, but I'm really impressed with the results and the power curve.
21 GT baseline + tune only 93 + tune only e85 (all stock 10 speed)
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