Load based vs inertia based dynos

[Cheapspeed]

I just spent some time reading the differences between dynojet and mustang dynos. As I understand it dynojets are inertia based and measure acceleration. Mustang dynos apply a load more to simulate real world conditions.

Based off what I read tuning on a dynojet could cause problems in real world driving.

I'm no expert just trying to understand the differences and why @Justin@Freektune; recommends using a dynojet to measure our cars.

Here is one of the articles I read. http://www.zerotohundred.com/newforu...rtia-dyno.html

[Design]

To be honest, I am not a fan of roller dynos at all. There are too many additional variables ranging from wheel slip to tire pressure that can impact both the output and consistency of the curve.

IMHO, hub dynos are the most consistent in a majority of environments. They are load based and factor out complications associated with rotational mass. But results are inflated 6-8% since all work is evaluated without a 20 lb wheel attached. So for that reason enthusiasts tend to dislike them.

To be fair, most of us looking at the numbers don't care about bragging rights. We just want reliability in the measurements taken at baseline vs. modded.

[JgamB]

I spose it doesn't much matter as long as it shows gains while you're hunting MBT on Eth/Meth/PI etc. If you can return to the same dyno for future upgrades, it should give you a decent indication if you spent your money wisely.

I prefer to go get trap speeds and use weight/velocity/distance/DA and use a calculator with 10% DTL.