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Dyno Tune

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Old Oct 1, 2011 | 11:45 PM
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Default 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.

Attached Thumbnails Dyno Tune-2ds4cnt.jpg  
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Old Oct 2, 2011 | 07:03 AM
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Nice job.
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Old Oct 2, 2011 | 09:44 AM
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Very nice. I can't wait to start modding mine...
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