Staggering results from VAP tune and pulley!

RRSTL3 said:

Earlier this winter I ordered the VAP crank pulley and tune. I had a couple of hiccups during the installation, but eventually got everything on and installed. Fast forward a few months, I took the car back out on the road and it was hard to get a “seat of the pants” comparison so I took the car to Low Boost Performance in Reno. The attached printout is weather and altitude corrected. The best result was 570 wheel horsepower using a Mustang Dyno. The calculated crank horsepower based on whatever metrics mustang uses was 700! View attachment 785
Interestingly, the lower pull was with the exhaust valves closed and the higher one was with them open. Not a huge difference, but the area under the arc is significant. Overall I’m very pleased with the results.

Click to expand...

RRSTL3 said:

Step one was pull the old tune from the car and send it to VAP. The main thing to consider was hooking up a battery charger, because apparently if the battery goes flat during the procedure it will brick your ecu. The process takes about 45 minutes. During the procedure various lights will flash, things kicking on and off, and gadgets starting and stopping.

You email the file back to VAP. They turned around the new tune within a couple of days.

While I was waiting on the new tune, I pulled off the factory pulley. It would have been an easy job if the engine were out of the car, but space is at a premium while installed. Use the belt tensioner to remove the supercharger belt. You need a large socket (24mm I think) to hold the crank and T50 to remove the fasteners from the pulleys. The fasteners are installed with blue loctite, so a bit tough to get out. Use a tap and die to clean the old loctite off of the threads. Install the new pulley and torque to the specs in the installation guide VAP provides.

You can then install the new belt. A word of caution: my new belt was an extremely tight fit. On the first installation I think I must have not gotten the belt fully on one of the pulleys. At about 4 miles, I noticed smoke from under the hood. I opened the hood and could see the belt was in distress. I gently headed home, but before I got there the belt broke and wiped out the plastic connection on the top of the brake vacuum pump leaving me with virtually no brakes. So again, make sure the belts are installed properly. Fast forward a couple of weeks and I received the new vacuum pump, a vacuum line that was also damaged and the new belt. But I digress…

After installing the new pulley and belt, you can install the new tune in the car. It is a much quicker procedure than pulling the old tune from the car. The new tune installation took 3-4 minutes. VAP still recommends using a battery charger to prevent bricking the ECU, but if your battery is fully charged my guess is you will be fine.

I am by no stretch of the imagination a mechanic, but I was able to complete the process. I went slowly, figured out the way to access all of the things I needed to reach and it went relatively smoothly, belt aside. VAP provides detailed, easily followed instructions when you purchase the device.

Good luck if you decide to move forward!

Click to expand...