LET Motorsports 06 CLS55 Custom Dynotune numbers
04-01-2009, 04:18 AM
#55
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C55,SL55,C63
just looking out for other members
You know what sucks is who ever the shop owner is with the Dyno-jet, should have been honest and said YOU CANT TUNE ON A DYNOJET! At least not with accurate and safe results.
Reasons why you cant tune on a dyno jet:
1)Once that drum gets spinning your engine does not have to work as hard to move the mass thats already moving. Inertia dyno's Like Dyno-Jet have very little if any load up top making it very hard to get accurate power numbers It like pushing a child on a swing set. It much easier to push them faster and higher when they are already swinging.... OR how my friend Rich puts it. "Its like the the Price is Right Wheel," Very easy to keep it spinning when its at speed, but try stopping it...
2)Without an accurate load on the car. Results on the street can and in most cases are different. I would bet with an accurate data logger your A/F results from a dyno-jet will be different. As your motor is working harder at WOT than on a dyno-jet.
3) its all Newtons 1st law of energy: Object at rest will remain at rest.. blabla Object in motion will remain at motion..blabla. How do you stop a drum spinning at 100+ mph if A/F takes a bad spike during the tuning process? Toss it in to neutral? Hit the brakes? Good luck stopping a huge spinning drum at that speed. Point is the drum will want to remain at the speed it is spinning at.
We all love our cars. Hell, even enough to sit up late at night and talk about them. I think people on the board would be doing themselves a service by tuning on a tunable load cell dyno like a Mustang, Dyno-Dynamics, or Maha rather than an inertia dyno like Dyno-Jet.
With over 300 personal dyno runs and counting and my experience with using a Dyno-Dynamics dyno. It bothers me when Shop owners say they can tune on a dyno-jet. I've seen countless cars come into Dyno-Comp in Scottsdale AZ for tuning after attempting to be tuned on a Dynojet. Like a MagnaCharged 6.0 GTO with tons of mods only able to put down 350whp??? Talk about a joke. The difference can be huge from trying to tune on an inertia type dyno to tuning on a load cell dyno.
Reasons why you cant tune on a dyno jet:
1)Once that drum gets spinning your engine does not have to work as hard to move the mass thats already moving. Inertia dyno's Like Dyno-Jet have very little if any load up top making it very hard to get accurate power numbers It like pushing a child on a swing set. It much easier to push them faster and higher when they are already swinging.... OR how my friend Rich puts it. "Its like the the Price is Right Wheel," Very easy to keep it spinning when its at speed, but try stopping it...
2)Without an accurate load on the car. Results on the street can and in most cases are different. I would bet with an accurate data logger your A/F results from a dyno-jet will be different. As your motor is working harder at WOT than on a dyno-jet.
3) its all Newtons 1st law of energy: Object at rest will remain at rest.. blabla Object in motion will remain at motion..blabla. How do you stop a drum spinning at 100+ mph if A/F takes a bad spike during the tuning process? Toss it in to neutral? Hit the brakes? Good luck stopping a huge spinning drum at that speed. Point is the drum will want to remain at the speed it is spinning at.
We all love our cars. Hell, even enough to sit up late at night and talk about them. I think people on the board would be doing themselves a service by tuning on a tunable load cell dyno like a Mustang, Dyno-Dynamics, or Maha rather than an inertia dyno like Dyno-Jet.
With over 300 personal dyno runs and counting and my experience with using a Dyno-Dynamics dyno. It bothers me when Shop owners say they can tune on a dyno-jet. I've seen countless cars come into Dyno-Comp in Scottsdale AZ for tuning after attempting to be tuned on a Dynojet. Like a MagnaCharged 6.0 GTO with tons of mods only able to put down 350whp??? Talk about a joke. The difference can be huge from trying to tune on an inertia type dyno to tuning on a load cell dyno.
04-01-2009, 07:43 AM
#56
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2006 E55
You are dead nuts on. The dynojet is mass only. Mustang, dynodynamics are eddy current/mass dyno that allow you to tune steady state full load at any RPM.
