Dyno Tune
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Dyno Tune
After finishing up the last of my mods, I decided to take the car over to Intense outside of Columbus, OH for a Dyno Tune. Prior to this, I had been getting tons of KR on a 3.5" pulley. I narrowed that down to a weak fuel pump so I had them replace the pump with a Walbro model they stocked. It brought the pressure up to 56 psi from 38.
The guys at Intense were great to work with. Initially they thought the car would handle a 3.2" pulley, but the tuner wasn't comfortable with the KR he saw after the first pull, didn't think he could tune it out.
(first pull w/ 3.2" pulley)
He worked with the tune on a 3.3" pulley instead. Best pull on the dyno was the last one, after the tune which was 242.3 whp / 345.9 torque. The baseline before the tune on the 3.3" pulley was 232 whp.
He mentioned there is a fair amount of valve float toward the top starting around 4700 rpm which is limiting the horsepower gains, and causing the boost to stack toward the end of the powerband. I was told the 1.9:1 rockers are iffy on stock springs, let alone ones that have 130k miles. He suggested 90# springs, saying that should yield at least another 10hp. Just when I thought I was done modding, I've got another thing to add to the list.
(with 3.3" pulley)
Because of the weak fuel pump, I hadn't really been able to try it out because of KR, after putting the headers, rockers, etc. on. Compared to stock, the thing pulls like a mule. Before, I could avoid wheelspin pretty easily just by easing into the throttle from a stop, but could go WOT pretty quickly. Now, mashing the gas at any speed below 25-30mph in 1st will send the wheels spinning. The torque steer is pretty obnoxious too.
The guys at Intense were great to work with. Initially they thought the car would handle a 3.2" pulley, but the tuner wasn't comfortable with the KR he saw after the first pull, didn't think he could tune it out.
(first pull w/ 3.2" pulley)
He worked with the tune on a 3.3" pulley instead. Best pull on the dyno was the last one, after the tune which was 242.3 whp / 345.9 torque. The baseline before the tune on the 3.3" pulley was 232 whp.
He mentioned there is a fair amount of valve float toward the top starting around 4700 rpm which is limiting the horsepower gains, and causing the boost to stack toward the end of the powerband. I was told the 1.9:1 rockers are iffy on stock springs, let alone ones that have 130k miles. He suggested 90# springs, saying that should yield at least another 10hp. Just when I thought I was done modding, I've got another thing to add to the list.
(with 3.3" pulley)
Because of the weak fuel pump, I hadn't really been able to try it out because of KR, after putting the headers, rockers, etc. on. Compared to stock, the thing pulls like a mule. Before, I could avoid wheelspin pretty easily just by easing into the throttle from a stop, but could go WOT pretty quickly. Now, mashing the gas at any speed below 25-30mph in 1st will send the wheels spinning. The torque steer is pretty obnoxious too.
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