I need help, 5$ bet against a stang owner..

[marleyskater420]

We both argue pointless crap about cars all the time..

Our argument at hand, is if turbos are load based, or rpm based, and if gearing dictates a load on the engine.

I say turbos are load based, he says rpm based.

I say different gearing will dictate a different load on the engine.
Like pulley ratios in a sense.

He says " there is no change in load on the engine when you get gears. the load is the weight and innertia of the car, and the car performs differently when you change your differential gears not because of load, but because you are going the same speed but with higher revs"

This is stupid, but I win 5$ if Im right, and I show him that Buick>Ford.

 

[marleyskater420]

edit:

He says that

"you say that rpm has nothing to do with turbo speed, im saying it does."

He says that rpm speed has a greater effect on spooling the turbo than the load.

I say the load of the turbo is what spools it, the rpm makes no difference.

If you put the turbo on a BB 545 it will spool at a different rpm than a 1.6l honda..the rpm had nothing to do with the spoolup, only the load that the engine produced on the turbo had to do with the spoolup.

By load I mean exhaust gases

 

[DavzGN]

It's load based. Simple way to prove it. Put car in neutral rev car to 2500-3000 RPM and show him how much boost shows on the Boost gauge. Then do the same thing with the car in gear and your foot on the brake and see how much boost you get.

Another way to show it is by driving at a steady rate on a flat road at 65mph you won't see any boost, but if you go 65mph up a steep hill you will often see some boost.

HTH
David

 

[UNGN]

It's not load OR RPM, but massflow.

If you had an infinite load, but limited the motor to 1200 RPM, the turbo will not spool, because the massflow is too low.

 

[KevinB]

Originally posted by UNGN
It's not load OR RPM, but massflow.

If you had an infinite load, but limited the motor to 1200 RPM, the turbo will not spool, because the massflow is too low.

If thats true, than what about diesel engines? They spin at low RPMS.

 

[UNGN]

Originally posted by KevinB
If thats true, than what about diesel engines? They spin at low RPMS.

And yet the Mass flow is still pretty high at those RPMS. A Diesel can make 400lbft of torque at 1000 rpm, but the thottle is wide open and lots of fuel/air is being consumed.

The massflow of an engine (the amount of air and fuel going in) is the direct reponse to the "Load" on the engine (the higher the load, the more throttle is needed to over come the load).

Put a 1200 stall converter in a Buick, set the parking brake and Try to get it to spool. The "load" is much higher than if there were a 3000 stall converter in the car, and yet the turbo won't spool, because the motor at 1200 rpm can't generate enough mass flow thru the turbine to spool the turbo.

 

[gnsrule]

A turbo spools from the expanding gas's. More heat, more expansion. Not flowage.
Thats how I learned it back in 81 from Wyo Tech.

 

[UNGN]

Originally posted by gnsrule
A turbo spools from the expanding gas's. More heat, more expansion. Not flowage.
Thats how I learned it back in 81 from Wyo Tech.

If you take the example I posted above, with a 1200 stall torque converter and a set parking brake, I dare you to put your hand on the exhaust elbow.

Are you telling me there is more "heat" in a car with a 3000 stall spooling turbo, than one at WOT with a 1200 RPM converter that isn't spooling?

More heat helps, but heat isn't spooling the turbo. "expanding gasses" are spooling the turbo, but it's the fact that there is 3X MORE gas at 3000 RPM vs. 1000 RPM that is the difference and not the small difference in temperature.