Strange times

A customer brought me his car recently to do a check up on the supercharger I installed a couple years ago. This car has never been as fast as other similar cars and I decided that we were going to get to the bottom of it.

 First we did a baseline performance run. Mike at Moto-East prepared a tune that had worked well in a similar car a which had produced a 60-100 run of about 8.5 seconds. I did this test on our "sick" car and got a time of 20sec. EEEK. something is clearly wrong here.

After checking all the usual possibilities, I realized I'd have to open up the motor and check physical cam timing.

With a dial indicator dropped into cylinder 1, I rotated the motor to a true Top Dead Center.

I was both dismayed and relieved to find that the cam timing was off by about 5deg.  Dismayed because this engine has never been opened up or had any major service to the best of the owners knowledge and it's hard to imagine the factory boning this so badly.  Relieved because finally we had something to point to as the cause of our poor performance.

Next we checked that the crank pulley was indexed properly with the crank. Once again, muffed. It was off by probably 10deg.

here's what it should look like

Time to fix this mess. Here are the specialty tools you'll need.

With the timing now corrected, we took the car out for a 60-100 time. Mind you we changed only the cam and crank timing. Didn't touch the tune. Immediately we laid down a 8.9 second time. Yes, thats an 11 second handicap this car had due to bad mechanical timing. It ran fine, gave no indication that things were wrong except it "felt" slow. 

We have yet to final tune the car, but I think the customer is going to be pretty happy with the fix :)

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