Elio Turbo

[slinches]

True, and if they were, they would get horrible mileage.

There are multiple design points that auto manufacturers target. Acceleration to 60 is one that sets the necessary peak power required. Another is a cruise speed to optimize for efficiency (probably in the 55-75 mph range, depending on the type of vehicle). Using a turbocharger lets you size your engine a bit smaller for better economy at cruise while retaining the top-end power for acceleration.

 

[Joshua Caldwell]

Hope it's an electric turbo. The turbo in the truck I'm in only fully spools up by the time I'm cresting the hill a bit too late to be useful.

 

[W. WIllie]

Is it a diesel?
What rpm are you turning at the "cresting of the hill"?
In my G1 I can "Full boost" around 2400 rpm. (6 psi)
Willie

 

[Joshua Caldwell]

Yup, I'll start the hill at around 1400rpm with already flooring it for a couple seconds before starting the hill. Sometimes the turbo kicks in immediately and I'm still around 1300 at the crest, sometimes it's late and I'm just a hair over 1000 and seconds from having to downshift and it never kicks in at all, usually it'll kick in about 3/4 up the hill but I will have lost a good 15mph by then. (Freightliner Cascadia)

 

[slinches]

Do you know if the turbo has variable guide vanes? If so, you could have an issue with the controller or the vane actuation. A fixed vane turbo should always spool up at the same rpm at full throttle (within a few seconds anyway).

 

[Coss]

Do you know if the turbo has variable guide vanes? If so, you could have an issue with the controller or the vane actuation. A fixed vane turbo should always spool up at the same rpm at full throttle (within a few seconds anyway).

I don't recall ever seeing an automotive turbo with variable guide vanes.
All of the automotive applications use a variable waste gate (some call it a pop off valve).
That's how a friend of mine blew out the entire bottom end of a 400 small block; he ran 100% propane (160 true octane) and was experimenting with a manually adjustable waste gate. Was out running around in the country (wide open road (and throttle) for many many miles) a horse crossed the road in front of him when he had the gate closed (no pop off valve); he slams on the brakes and found out why a manually adjustable gate is a bad idea. I found out about it because he called me to pick him up, and "oh yeah, bring your car hauler trailer "

 

[W. WIllie]

No POP OFF valve was the problem!
A waste gate and a pop off valve are two different items.
A waste gate regulates/limits the amount of BOOST.
A pop off valve relieves the pressure when the throttle is slammed shut.

 

[Joshua Caldwell]

Do you know if the turbo has variable guide vanes? If so, you could have an issue with the controller or the vane actuation. A fixed vane turbo should always spool up at the same rpm at full throttle (within a few seconds anyway).

not a clue, I do know that the engine has a fan issue where it will randomly go on full, even when the temp is below the normal operating range

 

[Coss]

No POP OFF valve was the problem!
A waste gate and a pop off valve are two different items.
A waste gate regulates/limits the amount of BOOST.
A pop off valve relieves the pressure when the throttle is slammed shut.

I mentioned that ".......... gate closed (no pop off valve); he slams on the brakes ........." He had taken it off while he was experimenting because he didn't want it to interfere with his tests.

 

[W. WIllie]

SO in REALITY it was "Driver Error", not the waste gate.
I'm surprised he didn't blow the turbo apart. Or did he?