Here's the background, then you can have a chuckle at my little adventure. 4 or 5 years back, I was forced to send my existing convertor off to get new flex plate lugs welded on due to the result of a flex plate bolt backing out. At the time, I was aware that my 60' times were a little soft, and that an extra 500-1000 rpm on the hit would probably bring it around.
So, the convertor gets redone and off we go to the race track. Sure enough, the 60' improves, but the car lays back .2-.4 seconds and drops 3 mph. It does, however get more consistent. After several rounds I actually get around to noticing that it's actually down several hundred RPM at the stripe. This is the opposite of what I expected, as I thought the ET/MPH loss was due to more slippage. At this point, I'm flummoxed, as the car is quicker in the 60', even at the 330, and slower all the rest of the way down track.
Because my 4.88 gear set was not in the best of shape, I took this opportunity to take advantage of the extra 5-600 rpm now available at the stripe and swapped out the 4.88's for 5.13's.
Result? The car picks up another couple of hundredth's in the 60, and not really a whole lot down track. Maybe .05, tops. It did however, become even more consistent. Run 'er and live with it, I say.
Fast forward a some more and a new set of lifters results in a cam lobe going away. All right, it's time to put a roller in it if the cam's coming out anyways.
So, out comes the old Mopar 528 solid and in goes a Comp 575 solid roller. There was a bit of a glitch with that but I got it solved. Off to the track.
Now, I haven't ran any 1/4 mile passes, but at our 1/8 mile track, my 60' times are back in the 1.60 range (soft) and my ET and MPH show no improvement over the old 528 when it had "not enough" convertor and "not enough" gear in it. Oh well. Run 'er. Right?
So the other day, my son helps me down load my GoPro footage to the PC so we can watch it on our TV in hi-def. That's when I noticed something interesting that you couldn't see clearly when replaying the GoPro through the iPad.
My friggin' convertor is barely flashing to 4 grand on the hit! It's dragging the motor down big time, and you can really tell on the video that it's struggling to power out of the hit.
I won't change out convertors this year, but I will this winter. Just need to have a few good months again before I tackle hauling that lump out of the car for a convertor change.
Stupid race cars!