Originally Posted by RPIpower
The way you assume you are making 15hp over stock is not accurate. Technical answers should be answered by, well, people with technical knowledge. Assuming that its the tune is not an accurate assumption. I can assure you that it is NOT the tune. Different dynos, different conditions, dyno operator, etc can effect the numbers. Did the dynojet have a load option? Tire pressure? Strap down tension? Fan? How do you know the mods you have all work well together? Was your mufflers designed to go with straight pipe? What type of gas? Did you get a bad tank of gas? These are all things than can effect your run and this is why we do extensive dyno testing to ensure that these errors are limited. We have countless amount of runs from our customers beating on cars that dynoed much higher. Its just a number man. Best way to see what your car is doing is test each mod alone. Not sure if your exhaust set is right? Try dynoing again with stock mufflers? Try with different gas? Try with different dyno operator? Remember, even the SAME model dyno operated by two shops or two dyno operators can give you completely different results.
Totally spot on.
Looking at the graphs it looks like the ECU is backing off at high rpm.
My initial thoughts would be poor fuel quality or highly inadequate cooling.
With those modifications I have no doubt your making around 370RWHP or 450-465 Fly.