One word best describes the experience Disaster! The new FAST XFI is susceptible to electrical noise and low voltage to a point that the car will not run with the supplied harness used by Kinetics for dyno runs and tuning.
I drove the car last Friday near my house and it quit two miles out. It was 97 degrees and really nasty. I was out there about 2 1/2 hours till I got a ride back to my house to get the trailer and pick up the car. I tried jumper batteries and charging it from another vehicle, still no start. At this point I was very tired , hot and unhappy. I called Scott and told him I wanted to pull the plug on Goodguys Pleasanton. He asked me to try and fix the issue so we could qualify for Scottsdale. I decided to put my battery charger on and let it charge about two hours. I went out about seven PM and tried it and it started immediately, jumping to an erroneous conclusions I assumed the battery was low and all was good. I loaded the car up along with all our other junk and got about 4 hours sleep before leaving for Pleasanton at 4:15 am. We unloaded there and all seemed normal until it was time to run, it leaked water because I overfilled the expansion tank and we had a pretty good
oil leak from the dry sump pump outlets too. This pissed the officials off so they booted us out of line to deal with our issues. We drained the overflow bottle and tighten the
oil lines and got back in line. The car made a mediocre run and quit at the finish line for no apparent reason. We made one more try and Scott went off course. At that point we decided to go after the
oil leak, unfortunately you have to pull the right hand headers to get at the hose ends a bad job in the garage and miserable in the field. When we finished everything we got back in line and it quit before he could even start. Are you seeing a pattern? I tested battery voltage during cranking and it was low 9's high 8's so we ran out and bought a crappy Optima red top for $270 at NAPA. They saw us coming! Got back in the line up and it started until he got near the course and quit again. It was now 5:00 pm so we brought the trailer over and loaded the car, generator and tools and moved it to trailer parking.
I am thinking that it must be an electrical issue probably voltage or crank sensor related. Went to bed about 10:00 pm and got up at 5:00 am to do electrical work. We ran a 10 gauge wire from the XFI to the battery and then soldered the crank trigger directly to the harness to eliminate a suspect
weatherpack connector. Sounds like not much but it took two hours so Scott missed the drivers meeting. Guess what, it still would not start so I pushed in on the rear XFI connector and it started right up. Simple, put a tie wrap on the connector and pull it and harness to the box. We took it to the course and unloaded it. Scott drove it around the lot and all was fine. He went up to the start and you know what is next right? It quit AGAIN!!!! I am ready at this point to pour gas on it and light it on fire. Well I didn't but I had Scott drive me around so I could watch the indicator lights. Seems that whenever it quit the injectors did not fire nor did the "points wire", light come on, more on this later.
Scott was offered a ride in Mike Maiers fine 65 Mustang with a Yates engine so we put the Cobra away after a very frustrating 3 days. They put me on suicide watch for the rest of Sunday. So I just helped with a little tuning advice until leaving for home.
Good things:
- FAST people think that is was slipping into Flash Mode because of noise spikes or low voltage caused by high ground currents so maybe it can be fixed.
- The engine feels stronger that the old one (we had to disconnect the secondaries) until I finish hooking up traction control
_ The engine is even louder than the old one good because loud usually = HP
bad because loud means new mufflers
- The engine revs like a banshee Scott touched 9000 on his first run with ease it accelerates really hard too
- The new needle bearing rear A arms have produced slightly better grip because of friction reduction
Bad things: I am going to have to provide separate ground circuits for 5 separate pins on the ECU back to the battery 3 are 10 gauge to try and prevent noise contamination.
I will also run a separate power lead as it is installed all ready and re-pin several of the main harness connectors because they may not be making full contact.
If this does not work I will be buying a Holley system to run the car.
It really is a shame the car will blow the tires off in second gear at 30 mph
which means that we will now have explosive power off those GoodGuys U turns at 15 mph in low. It actually feels faster than the old engine and it was no slouch, looks like higher revs and a deeper gear were the answer but won't know for awhile. It is has fuel cut off at 9300! If only the electronics were on a par with the mechanicals. I will post here when I get it fixed with what ever fixed it.