AEM Dyno-shaft permanent inline driveshaft dynamometer

[nando]

I've actually done it, you can measure a significant difference even at 25mph. You can see it from secondary factors to, for example, the car will go leaner because there is more air. you don't need to know the exact flow rate if you know what to look for. :)

if you only changed the intake, and needed to add fuel to reach the same AFR (because of cooler temps), or can see that MAP increased significantly (less restriction), then you can know you're making more power. Don't need a dyno for that, you just can't quantify the exact difference without verification (I've done that too). But even then, you can get pretty close with good assumptions and math (10% more MAP, about 10% more air& fuel, about 10% more power, minus efficiency losses).

[nrubenstein]

you can do that without a $1200 tool if you can datalog already. all you need is an IAT measurement. :)

With all due respect, IAT isn't the only factor, and may not even be the biggest one on a car in constant motion. IAT doesn't measure flow or turbulence, or whether or not the car is actually making more power. It just measures temperature, which only really matter when you're driving slowly unless your airflow is unusually bad.

[nando]

you can do that without a $1200 tool if you can datalog already. all you need is an IAT measurement. :)

[nrubenstein]

no load brake capabilities, no care. :p

plus I could afford an entire DAY on a chassis dyno at that price. normally you only need an hour or two. it's a neat idea but one day the things will cost $200 and then it will be a neat toy.

Don't you get a load brake from wind resistance and the mass of the car? :p

I mean, the facilities required for using this effectively are significant - basically you need access to a runway. On the same token, though, I'd think you could get a lot of useful data that isn't available on a dyno. You know, like whether or not that intake actually works.

[nando]

^ ... what?

nobody knows, not even F34R...

[acolella76]

^ ... what?

[nando]

I don't see how it would help you tune a car. You would still have to be doing high speed runs somewhere and you would still have to be logging AFR, Alpha, throttle position etc. Might as well do it on a dyno with a load brake.

you could legitimately use it on a racetrack or drag strip.

However, I'm assuming professional teams already do stuff like this, considering how much computing and logging power they already have.

it's unclear to me what the market for this is, other than a cool (and expensive) toy. I want one but I don't know what I'd use it for. :p

[TwoJ's]

I don't see how it would help you tune a car. You would still have to be doing high speed runs somewhere and you would still have to be logging AFR, Alpha, throttle position etc. Might as well do it on a dyno with a load brake.

[e30moneypit]

interesting----- i rememember seeing this idea presented at televised sema event I believe. Prob about 7-8 years ago by a 16-17 year old kid. He had a working prototype he built in his school lab or something...details are fuzzy but back then it was off by 5% and cost him about 2-300 to make.

hope he got a sold sum plus royalties for his invention.

[nando]

no load brake capabilities, no care. :p

plus I could afford an entire DAY on a chassis dyno at that price. normally you only need an hour or two. it's a neat idea but one day the things will cost $200 and then it will be a neat toy.

[rcfanatic]

With that logic no one would ever get their cars painted, big brake kits, 5 lug conversions, turbocharging, etc.

[mr ilia]

good price, but I will wait for boxing day....

[devon.818]

borris, cough borris.

[KenC]

Very cool, but I don't see too many people spending that kind of money on their E30's...

There are like six e30s in the world that make enough power to even care about it.

[rcfanatic]

Very cool, but I don't see too many people spending that kind of money on their E30's...

Yeah I just noticed the price tag. Seems like the best option though if you can't find a place to tune your engine for you