I recently got my car running again with a slightly larger cam and a little more stall. At the track my car launches alot harder but my mph is off by almost 2. I'm obviously making more torque with the higher lift cam because with this same stall (3200) and the smaller cam, I could only pull 1.64 60s . Now I've gotten it down to 1.57. On the dyno, the power hovered around 325 from 5k to around 5600. At that point, when the converter goes into lockup, the power shoots up to 363. Unfortunately with my gearing (3.73s), I spend little time in lockup, so I don't really benefit from the increased power it gives. I don't want to go to 4.10s which would probably be ideal. Is it possible that this converter is just too loose costing me too much power?
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The dyno is not a good comparison when doing a torque converter test. Remember that at the track the conditions are completely different. I have seen many times that when someone locks up the torque converter in 3rd gear they will lose mph, why, because the TC is no longer multiplying torque (however little it may be). When you lock up the TC, now all you have is the higher pumping losses of the automatic transmission when compared to a stick. Also the looser the torque converter (higher stall) the dyno will show even more losses in most cases. You can take a stickshift and dyno it & it will show higher HP numbers across the board when compared to an automatic (all other factors being equal), yet at the drags you could see almost identical ET's & MPH's, this is due to the torque converters ability to multiply torque.

 

Like he said but to add again also, the dyno doesn't not give you a accurate reading for the TC. Track testing is the only way. If your 60' time is down, then that's a good thing. I am in the process of pulling my TC and uping the stall. PI Vig. from 2800 to 3600 or more. You want the stall about 500-700 rpms less than where you car makes peak torque according to them. Also engine combo will make a difference as to where it will stall also.

If your not going thru the traps at your rpm range you want then gear and tires need to be played with to get you into the range you need. TC gets you off the line.

 

I learned this past summer that the dyno is not place to try to get impressive numbers with a loose converter, I have an EDGE 3400 stall. Last april I was running constiant 12.3 with MPH around 110-111. In June I had the car dynoed and only put down 277 HP and 243 TQ . To say I was very dissapointed. There were internally stock LT1 M6 cars putting down more than me at the event. I got talking with the dyno operator(who owns a 9 sec LT1) and he said when he put a high stall auto in the car he lost 150 RWHP, but got a lower ET.

I wouldn't worry about the numbers, they can be used as a baseline for future testing on a dyno though.