Bradan F355 baseline dyno

+1

 

wrong wrong wrong

 

correct correct correct


i heard dynojet has came out with a load bearing recently?....

 

See my thread in the 308/328 section. Maha dynos are similar to Mustang dynos and yield very similar rear wheel numbers, but are just stupidly accurate as they calculate drivetrain loss throughout the rev range. I have a sheet from a 328 posted with a maha dyno.

 

I'm extremely impressed by your comprehensive reply. Thanks for sharing your vast knowledge and impeccable insight.

 

Who really cares what numbers a dyno shows? As long as the engine, or car, is baselined, then worked on and re-dynoed on the same dyno to verify results.
I had a 406 dirt track engine a few years ago that dynoed at 540 hp (with iron heads and intake and a 2bbl carb- per rules) that would 3/4 lap the rest of the field, when some of the competitors engines supposedly dynoed at 600+ hp.
Comparing one dyno to another is apples to oranges...even the same dyno with different operators will show differences.
Last I heard, sanctioning bodies have races for cars, not dynos.

 

u r welcome....

 

+1 you are 100% right. That being said, some people (myself included) sleep more peacefully at night knowing their engine is as new or better than new. I guess it's an ego thing or something.

 

In any dyno output, the SHAPE of the dyno curve(s) is a lot more valuable than the peak HP number of peak TQ number.

And then again, after any modification, the difference in the shape of the curve tells you a lot more about what the modification did (or was worth) than the actual HP or TQ numbers.

 

+1 .......

 

Thanks.
I guess I'll go back and save all 4000+ pulls on my dyno as graphs....

 

It seems that some people like to use their dyno sheets as bragging rights in the tavern. Sort of like "this magazine sais my car is faster than your car" I guess a lot of cars can make big power for three seconds before they blow up. For me its lap times that matter not dyno numbers. They don't get my respect untill they get off the track after 4 of 5 hard sessions in the heat of summer at the end of the day and still move under their own power.

 

David- Most of us do not do that and have no desire to do that.

Taz
Terry Phillips

 

Sorry Taz, didn't mean that towards anyone here, I see it more in the "other car" circles. Ha

 

David- No sweat. I understand. A Ferrari street car and a formula race car make really good garage mates, even though I only have the former.

Funny, because I am installing MovIt Ceramic brakes on my car (movit.com), but will never use them to their full potential.

Taz
Terry Phillips

 

Your local cartooner is wrong.

Neither a mustang nor a dynojet is inherently "more accurate" than the other.

As enginefxr said, you cannot compare numbers from different types of dynos - it doesn't work.

Accuracy and repeatability come down to the environmental controls, and the statistical
methods used when trying to compare numbers FROM THE SAME DYNO. As well as the
methods actually used when dynoing a vehicle.

99.9% of the cartooners (car tuners) out there wouldn't know statistics or proper dyno procedure
from a tuna sandwich.

 

Tuna sammage? Yummy

Our dynojet is not climate controlled but I have found a reasonable amount of accuracy and repeatability when testing parts within a short enough time to where there is not a great change in ambient conditions.

Here is an example for those interested-

http://forums.corvetteforum.com/c6-z06-discussion/2373189-speed-inc-fast-lsx-r-nw-102mm-tb-dyno-test.html

 

So where do horsepower and torque figures come from that automakers publish when different dyno's produce different numbers?

Which dyno's numbers are more reliable? They can't both be right, can they?

Either may be fine for comparison purposes on the same dyno to measure change after modifications but which one is more accurate?

They can't both be accurate if they produce different numbers.

Kai

 

An engine dyno - under tightly controlled environmental conditions in the dyno cell.

This number will always be greater than a wheel horsepower rating taken from ANY dyno
which is reading horsepower from the wheels.

The numbers will be different, but both will be "accurate" since there are losses in the
drivetrain due to friction and inertia. The characterization of these losses is something
best left for another thread.

Jim

 

http://www.movitbrakes.com/en/