On 3 hours of sleep, I ran down to get some 100 octane race gas, threw some more 92 into the SSM car, and we loaded it up into my dad’s trailer to haul down to the dyno (the car still doesn’t have a hood or fenders, and it’s an unknown drivetrain, so towing seemed to be a good idea — this proved to be a good decision). We unloaded the car, I quickly wired up the TPS while Andre (of Pina Motorsports) started laying in a base tune and configuring anything I’d missed on the car, and then we loaded it onto the dyno. We made it about 1/3 of the way through the base fuel map when suddenly the motor backfired lightly, cut out, and refused to even pretend to start again.
We debugged a bit and found that the cam/crank sensors weren’t syncing properly, and were in fact syncing largely randomly. We tried messing with it for a bit, but to no avail. We did a quick compression check on #1 and found no compression, which implied something far more serious was wrong and decided to call it a day. We loaded up the car and brought it back home, tail between our legs.
After getting some sleep (I was a zombie at this point), the next day I tore the valve cover and the timing covers off the motor and started toying around. I quickly realized that while the cams were in sync relative to each other, and the crank pulley was correctly marking TDC (verified), they were nowhere close to correct relative to each other. I assumed the Gates belt I’d used stretched and the belt had slipped, so I ordered a new timing belt and tensioner spring and started messing with other stuff in the car.
The next day, I figured I should tear the rest of the front of the motor off so that when the belt got there, I could just throw it on. While I was disassembling, I realized that I could spin the crank and the cams weren’t spinning. When I got the crank pulley off, I realized the issue. I’m using a bolt-on 6 rib pulley from Fast Forward Superchargers that mounts into the stock 4 bolts on the front of the pulley. What I did not notice, however, is that the hole in the center is about 1mm too small for the crank bolt to pass through. So, while everything torqued together properly, the bolt was over 1cm too far out from where it needed to be, so the woodruff key was no longer held in place. After running long enough, it managed to vibrate its way out of the timing pulley and let it spin freely on the crank, while holding the normal crank pulley in place. With that mystery solved, I properly reassembled everything in the correct order, and went back to finishing up some rewiring while waiting for the coil that I left at the dyno to be mailed to me.
I’m using this delay to redo some wiring in the bay that needed to happen — moving things like the TPS, IAC, IAT, etc. around in the front harness to properly reflect where they’d moved to in the final configuration, which should clean up the engine bay quite a bit and make the car easier to work on. I’m also installing a console-switchable fan onto the intercooler for waiting in grid. Tomorrow the coil should arrive and I can try firing the car up again, and then take it to the dyno later this week to try again, hopefully with more success…
