Ford Fusion V6 Sport Forum banner
81 - 84 of 84 Posts

·
Registered
Joined
·
1,207 Posts
There are numerous “Trap Speed Calculators” available online. They’re only estimates but offer a generic perspective for comparison as one progresses thu data logging & tune revisions.
My understanding is those formulas calculate estimated wheel hp since they rely on trap speed, and E/T factors relative to weight and distance. Results from chassis dynos and time slips would represent wheel hp whereas it would take putting the engine on a engine (crank) dynamometer to get crank hp. The reason I’m curious is because there’s been some interesting discussions about driveline losses with these cars that have stirred up a lot of opinions. TwinForceFusion did a YouTube video where he used a formula to get from his chassis dyno numbers to crank numbers and there was quite a bit of dissent over his conclusions. I’ve often wondered how inefficient our driveline and accessory load really is (or isn’t). It’s all just semantics, because I’m a rock-steady believer in time slips as the final arbiter of real-world power, but I’m curious nonetheless.
Those are some nice numbers by the way, and I like the look of your car. I’ve attached my PBs. Since they were back-to-back, I consider them validated. I’ve run higher trap speeds with different size tires but this is the best ETs. My car routinely runs anywhere from high 12.70s to low 12.40s in a single night! It’s frustrating, but I’ve learned to deal with it!
Font Paper Paper product Document Monochrome
 
  • Like
Reactions: Wojtas and Spencer

·
Registered
Joined
·
18 Posts
My understanding is those formulas calculate estimated wheel hp since they rely on trap speed, and E/T factors relative to weight and distance. Results from chassis dynos and time slips would represent wheel hp whereas it would take putting the engine on a engine (crank) dynamometer to get crank hp. The reason I’m curious is because there’s been some interesting discussions about driveline losses with these cars that have stirred up a lot of opinions. TwinForceFusion did a YouTube video where he used a formula to get from his chassis dyno numbers to crank numbers and there was quite a bit of dissent over his conclusions. I’ve often wondered how inefficient our driveline and accessory load really is (or isn’t). It’s all just semantics, because I’m a rock-steady believer in time slips as the final arbiter of real-world power, but I’m curious nonetheless.
Those are some nice numbers by the way, and I like the look of your car. I’ve attached my PBs. Since they were back-to-back, I consider them validated. I’ve run higher trap speeds with different size tires but this is the best ETs. My car routinely runs anywhere from high 12.70s to low 12.40s in a single night! It’s frustrating, but I’ve learned to deal with it! View attachment 30162
Thanks for the kind words on my car! I’ve put a lot of love into her!!

We’re definitely on the same sheet of music! Trap Speed calculators are FAR from precise & only estimates IMO.. Dyno is the only way to accurately get numbers & even those vacillate with MANY variables.

It’s why time(s) are really the quantifiable metric meaningful to me. I do believe Twin Force, Marcelino & I have the most modded cars for the larger platform for what that matters…

Regarding power loss from crank to tires, the Sho community has a nice solution with the Tranny Mount developed by Tony to mitigate movement and subsequent loss of power transfer. The FFS & MKZ platforms could benefit from a similar trans mount. I have one sitting in my trunk right now that needs to be installed / tested. Others have said it vibrates the heck out of our cars. I’m hesitant to go that route at the moment…Instincts tell me FFS / MKZ lose 20-25% power crank to wheel because our PTU’s are an afterthought for a FWD bias tranny…
 

·
Registered
Joined
·
1,207 Posts
I have a trans mount and I wouldn’t do it again given the chance. The vibration and noise transmitted into the cabin is significant. It really takes away from the character of the car as a grand tourer.
 
  • Like
Reactions: Spencer and Vidmo

·
Registered
Joined
·
1,366 Posts
I bought one, lasted about a week, laying on a shelf where it will stay for now till I decide to sell it.
 
  • Like
Reactions: Spencer
81 - 84 of 84 Posts
Top