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Discussion Starter #1
Ever since the first mod we have put on these cars, there has always been a question of "Why are my dyno numbers so low?" I think I have found the answer. Below is a graph of 6 different dyno runs all done in 3rd gear. The parameter you are looking at is called gear ratio and it is a measurement that helps identify converter slip in addition to many other possibilities. What I have noticed is that the more power you make, the more the converter slips to the point of hurting dyno numbers. I first noticed then when the exact same car on 2 different days dynoed 30hp less than the original dyno from the previous day. We let the car cool down and all the power came back. The only difference was with this gear ratio, the lower run was significantly higher than the higher dyno number. Since I know it isnt tire spin (another problem seen by logging gear ratio), the only other possibility is over-powering the converter in the car to the point that the numbers are significantly lower than actual results. I will outline peak tq numbers for each of the colored lines below to show that as you increase in power, you are also increasing the amount of slipping in the converter and therefor not seeing the actual gain from said product. Green and Dark Blue are right on top of each other, but there is minimal differences in tq between them
Light Blue: 349rwtq
Green: 379rwtq
Dark Blue: 383rwtq
Red: 401rwtq
Maroon: 426rwtq
Pink: 474rwtq

So as you can see, I think allot of peoples inaccurate dyno numbers (especially heavily modded) are due to an increase in converter slip. I am told that the Mopar TCM aids in converter lockup, so we ordered 2 of the Mopar TCM's and we will be testing them in numerous vehicles to see if it does indeed aid in converter lockup and increase the hp/tq numbers. Stay Tuned.
 

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Any idea when Diablo is going to come out with something to help this?
 
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