Join Date: Mar 2010
Location: Wentzville, Mo.
Mentioned: 0 Post(s)
Tagged: 1 Thread(s)
Quoted: 15 Post(s)
Assume a 10-15% parasitic loss through the drivetrain and I'd say you are low. BUT........
Did you do any tuning at all while on the dyno? Did it have a wideband for A/F? Are those "standard" or "corrected" numbers"; i.e if you live in Colorado were they corrected for sea level elevation and temperature?
What kind of dynamometer, Dynojet, Mustang, other? Some dynos read lower than others depending on their configuration. I've seen unscrupulous dyno operators also change the parameters on their dynos to get the big numbers. Then all the guys want to run their cars on that dyno to get hero numbers. My personal preference is the Dynojet 248 series. They are pretty much the industry standard and are used by Nascar.
Realistically dynos are tuning aids so it would have been beneficial to have a before and after if you recently switched from the single four to the dual quads.
Describing your drivability problems a competent tuner/dyno operator on the right type of dyno should have been able to work that out. Some dyno's are only about the "hero" numbers but others use them for drivability tuning at light and part throttle.
Dyno's are great tuning aids if used properly. If your car is running top notch and you just want some bragging rights then by all means just jump on there and get your numbers. BUT.....if you are having issues this is where the dynamometer and a good tuner will shine. I've literally seen guys gaining over 50 rwhp throughout the rpm range with good tuning on a dyno.
Lastly and more importantly, can you post the dyno sheet with the A/F ratio so we can see it?