Dynometer

[curtie94]

OK so I'm going to school for auto and at my college we are getting a our first dynometer in a few weeks. My question is are dyno's bad for the engine at all. If the engine is old will it withstand the dyno. I know it adds resistance.

My teacher says that we will try different things like make our own cold air intake and see if it acts the same as an expensive one. It should be fun.

[Mista Juice]

ummmm... shouldnt you be able to get the answer to this through your school?

[evil_demon_01]

I know it adds resistance.

If a dyno was bad for an engine, do you really think people would use them?

How much resistance do you think a dyno adds?
It is the same as a 3rd/4th gear pull.

[deevergote]

Essentially, it's the same resistance as you'd get simply driving the car. That's the whole point. A dyno is supposed to reproduce real-world effects, so the results can be translated to a car that is driven on the street.

[MortsAccord]

Even i it was more resistance than typically seen on a road, it would be no harder on the car than driving a steep hill in high gear.

If it added resistance during the pull the engine would slow its rpm climb or even loose momentum, both the same as driving a steep hill and having to gear down. Lol @ this question though.

[wed3k]

lol, depends on how much you want to load it.

[RyanD]

sounds to me like you're afraid you will blow you engine up. no worries just drive it like you would if you floor it on the street

[Xsjado]

why do so many cars blow up on dynos?

[GeoffM]

why do so many cars blow up on dynos?

Seems to be more and more common nowadays.

[MortsAccord]

why do so many cars blow up on dynos?

Because people are stupid. They modify their cars to the limit of their components and forget that they are running in 4th gear which would give them about 100+ mph of wind on their engine bay. They instead stick a tiny blower motor across the front of the car expecting it to whisk away the amount of heat traveling 100MPH or more would.


They do repedative dyno runs trying to get the most out of their dyno session...
Car gets massively heat soaked, on top of producing much more power than stock and blows the Fug up.

[Xsjado]

Surely the wind and airflow can be replicated artificialy
Anyone heard of a vbox3i?

[deevergote]

How would a vbox3i help an engine from getting heat soaked?
MortsAccord wasn't referring to the ECU not compensating for a lack of wind. He was talking about the fact that a car on a dyno is not getting airflow through the radiator, thus it will quickly succumb to the effects of heat, even with a fan blowing on it (a fan is not a substitute for 100mph highway speeds that would usually accompany that engine speed in 4th gear.)

People also push their cars to the limit, and alter the ECU and mechanical tuning to try to squeeze the most out of the engine. Pushing an engine to the limit while risking heat soak is definitely a good way to blow up an engine.


The dyno itself is no more harmful than driving the car normally. All it does is provide resistance to the wheels. It's a roller that simulates the resistance of driving on the street, while logging the power put through the wheels.

[wed3k]

inexperienced tuners, engine builds that blow up, parts going south, things just happen...

[MortsAccord]

Surely the wind and airflow can be replicated artificialy
Anyone heard of a vbox3i?

You go ahead and build a room around a dyno that will simulate 100-150mph winds that a car actually sees duing that kind of acceleration on the street. Let me know when your done.

[wed3k]

You go ahead and build a room around a dyno that will simulate 100-150mph winds that a car actually sees duing that kind of acceleration on the street. Let me know when your done.

i don't have that much experience but i smog cars on a dyno and have seen plenty of cars overheat when they don't have a fan in front of them.

sometimes the fan doesn't even do enough.