Tucker

[quote=wild stray,February 16, 2005, 11:31 PM]
The dyno shop has dynoed several cars and brought them to another shop with a Dyno Jet to check and it is with in 1-3 RWHP of a Dyno jet. Very accurate #'s.
Great shop too. DTP!

DozerzPony

Is there a special Dyno for every vehicle?

RRRoamer

Only if you have a MUSTANG!

DozerzPony

Why the different Dyno?

RRRoamer

Sorry DozerzPony. My post above was just a smart hiney remark. DynoJet and Mustang are rolling road dyno manufactures.

There are several different types of dynos: (a few of them...)

1) Water brake engine dyno - engine comes out and is bolted to a test stand. Water is used to load the engine. Think of it as a VERY big water pump with a controlled intake valve.

2) Eddy Current engine dyno - As above, only using electrical resistance to vary the load on the engine. Similar to using a large electric motor feeding a variable load.

3) Rolling road - The car is strapped down with the drive wheels (front or rear) sitting on a very large, very heavy roller. The car drives the roller up to speed. This is an accelleration test only! You can NOT test steady state power on an engine with a rolling road because you can not create a static load. The only load the engine sees is the moment of inerta of spinning up a large weight. Mustang and Dynojet use this type of dyno

4) Hub mount eddy current dynos - Sort of a rolling road without the road. The loaders are attached directly to the hub of the car. You can use 2 or 4 of these to enable you to dyno all wheel drive cars. The main advantage is that you do not have to pull the engine to dyno an all wheel drive vehicle with this system

5) etc.

They all have their pros and cons and you have to be VERY careful if you want to compare the results form dyno A to dyno B. It gets REAL ugly if A and B are not the exact same type and model of dyno. They all work much better in testing modifications and tunes to see what improvements you made. I almost have to laugh when I see a statement like "my car made 296.7hp" because the error on the measurement will be measured in hp, not 1/10 hp.

I hope this clears it up a bit for you.

Purple Hayz

Roamer....nice summary

I learned more about dynos in your post than in the last 5 years of forum browsing....

much appreciated B)

mr black

EDIT- NEVER MIND- I now see the difference in numbers from this thread vs. your sig is due to your changing air intakes.

Also, curious as to why your a/f was up at 16:1 before the tune when most other people are way rich before an SCT flash?

DozerzPony

Thanks Roamer!!!