turbo charging

[2.2 Straight six]

Originally Posted by INF3RN0666

Think about having a dual forced induction system. Super charger gives you boost at low RPM, turbo charger gives you much more boost at high RPM. Why spend money on two turbos if the people above me said they won't be very effective anyways.

That's called twin-charging. the Golf GT and VW Bluemotion (i think that's what it's called) both use it. there's also a car at my college being built by a teacher that uses a supercharger and a garrett variable-van turbo.

using the vacuum lines, when a certain pressure is reached, an actuator opens a valve and the supercharger is bypassed.

[beef_bourito]

why would he twin charge a car with a variable vane turbo? wouldn't the extra weight negate any benefits from the reduced lag times because they'd be so small

[KiwiBacon]

Originally Posted by 2.2 Straight six

there's also a car at my college being built by a teacher that uses a supercharger and a garrett variable-van turbo.

There's a guy on clubisuzu who did that to his Isuzu 4JB1T engine. That's a 2.8L 4cyl diesel.
Last I heard he was having engine troubles which were unrelated to his boosting (block was cracked prior).

On a petrol engine there're several big problems to work around. One of the main ones is what to do with that much boost?

I plan to fit staged turbos to my diesel truck, variable vane for the small one.
It's a work in progress.

[2.2 Straight six]

this is on an 8-valve Golf MK II GTi. garrett varable-vane (looks like a T3) and an AMG supercharger. it sounds mental. serious machine, they're looking for 350bhp @ the fly. it's going to be used to hillclimbing. i'll try get some pics today.

[KiwiBacon]

Originally Posted by 2.2 Straight six

this is on an 8-valve Golf MK II GTi. garrett varable-vane (looks like a T3) and an AMG supercharger. it sounds mental. serious machine, they're looking for 350bhp @ the fly. it's going to be used to hillclimbing. i'll try get some pics today.

You'll get more power on a fixed geometry turbo than you will on a variable vane. More efficient turbine so you get less backpressure.

Seems like a redundant experiment if going fast is the goal, but worthwhile if the goal is to build something interesting and different.

[2.2 Straight six]

i dunno the goal, they told me they wanted the supercharger because there's no lag, then when the turbo's spooled a valve opens and bypasses the blower. but with a varable-vane that seems pointless, seeing as how the turbo pretty much has it covered.

either way, it's an awesome car. sounds like a beast when they give it some.