Dyno ?, Numbers don't add up
So after looking at different dyno graphs, websites, posts, etc. the numbers aren't adding up.
If you go to EC their dyno shows 282 stock, 328 after 65mm pulley & tune. Makes sense.
NW is saying about 30hp for the CAI. You look at their dyno for their custom intakes and the number is 316hp before the intakes (with ASP pulley, CAI, tune). Then 360+ with the intakes. Shouldn't they be around 358hp before the intakes and over 400 with. That's a big difference. What am I missing? If 360hp is the right number then something along the line isn't adding what it claims to add.
I realize different dynos, but something is off...
If you go to EC their dyno shows 282 stock, 328 after 65mm pulley & tune. Makes sense.
NW is saying about 30hp for the CAI. You look at their dyno for their custom intakes and the number is 316hp before the intakes (with ASP pulley, CAI, tune). Then 360+ with the intakes. Shouldn't they be around 358hp before the intakes and over 400 with. That's a big difference. What am I missing? If 360hp is the right number then something along the line isn't adding what it claims to add.
I realize different dynos, but something is off...
That 282whp stock seems low. I've seen graphs of SL500's pull that stock on dynojet's and their rated 30+ crank hp lower.
I bet EC was on a dyno that reads low like a and Needswings was on one that reads high.
I bet EC was on a dyno that reads low like a and Needswings was on one that reads high.
different dynos different number different cars different mods. soooo many factors.
Adam has all mods available and get 366 rwhp. a e55 amg got 360 rwhp on same dyno. e55 had new pump and some other small air intake mod.
Adam has all mods available and get 366 rwhp. a e55 amg got 360 rwhp on same dyno. e55 had new pump and some other small air intake mod.
Also there are many different ways of measuring horsepower (SAE gross and net, rear wheel, EU likes KW, and most are fudged to some extent such as corrections to STP (standard temperature and pressure).
When quoting numbers it is important to also say what the parameters used were else they have little meaning.
I prefer torque curves anyway, the area under the curve tells more about acceleration potential.
When quoting numbers it is important to also say what the parameters used were else they have little meaning.
I prefer torque curves anyway, the area under the curve tells more about acceleration potential.
That is weird. E55's are rated stock crank at 469.. That's more than 23% drivetrain loss. That puts the SRT at 470+ at the crank. That seems pretty damn high without spray.
EDIT: Thinking about it, 366rwhp for a heavily modded SRT doesn't seem that high, nvm. 360 for a 55 definitely seems low though.
Last edited by sk8erjosh09; Jan 2, 2014 at 01:36 PM.
I used to figure about a 30% loss between gross and net, both are measured at the crank. I'd figure at least another 10-15% to RWHP but then everything has "correction factors".
Even back in the Toledo days a good operator could add "Kentucky windage" to the readings used to say the only way a F*rd 390 made 300 hp was to crank it wide open, dump in the load, and see how far the needle swung.
This is a small one. Those in the GM dyno lab were a lot bigger. And green.
Even back in the Toledo days a good operator could add "Kentucky windage" to the readings used to say the only way a F*rd 390 made 300 hp was to crank it wide open, dump in the load, and see how far the needle swung.
This is a small one. Those in the GM dyno lab were a lot bigger. And green.
Last edited by Padgett; Jan 2, 2014 at 01:48 PM.
We really need one of those "LIKE" buttons!



