Oilless turbos, low mount or rear mount?

[Sammakko]

Ok, so there are many multiple turbo kit / placement options out there, but none of them are very streamlined, IMO. the low mount turbos require oil scavenging pumps, the high mount turbos place the unit really close to heat-sensitive parts, and both add weight to the "wrong" end of the car.

Not a lot of info on the STS/Rearmount setup that i've read, and that got me thinking.

Why not use an oilless turbo? mounting options are much better, as the location and mounting position are not restricted by oil flow through the CHRA.

thoughts?

[Spartarus]

The STS uses Comp oilless turbo, but still has to run lines from the engine bay. Oilless turbos still need cooling, the Comp turbos have a water jacket, hard lines follow the turbo charge piping back to the engine bay.

[Sammakko]

Originally Posted by Spartarus

The STS uses Comp oilless turbo, but still has to run lines from the engine bay. Oilless turbos still need cooling, the Comp turbos have a water jacket, hard lines follow the turbo charge piping back to the engine bay.

STS is also out of business.. yes, i'm aware they still need water, there's no reason to run it all the way from the stock cooling system, is there? could you not use a completely separate cooling system?

[AVOturboworld]

Originally Posted by Sammakko

STS is also out of business.. yes, i'm aware they still need water, there's no reason to run it all the way from the stock cooling system, is there? could you not use a completely separate cooling system?

You'd then need to build a separate cooling system with it's own radiator and water pump. Hardly cost or space effective.

[Spartarus]

Originally Posted by Sammakko

STS is also out of business.. yes, i'm aware they still need water, there's no reason to run it all the way from the stock cooling system, is there? could you not use a completely separate cooling system?

There's no reason not to run coolant from the engine bay. The performance cost is zero and the weight gain is negligible. There are several reasons not to build an independent loop.

You could build an independent loop in back but it wouldn't save any weight given the requirement for another radiator and reservoir. The cost of a radiator, electric pump, reservior (with provisions for expansion), and fittings/lines, pump relay and/or thermostat is significant. This solution adds several new electrical and mechanical failure points. The stock cooling system has all of these wonderful features already; you have to run piping anyway, just bracket the water hard lines onto the charge piping. Anything that's going to burst the water lines is going to break your charge piping too. Finding a suitable location for a radiator in the rear of this car is no trifling matter either.

Not to say rear mount turbos won't work in this car, but they work better and are much more responsive in low-boost, high-displacement, non-intercooled applications.

[Sammakko]

Originally Posted by Spartarus

There's no reason not to run coolant from the engine bay. The performance cost is zero and the weight gain is negligible. There are several reasons not to build an independent loop.

You could build an independent loop in back but it wouldn't save any weight given the requirement for another radiator and reservoir. The cost of a radiator, electric pump, reservior (with provisions for expansion), and fittings/lines, pump relay and/or thermostat is significant. This solution adds several new electrical and mechanical failure points. The stock cooling system has all of these wonderful features already; you have to run piping anyway, just bracket the water hard lines onto the charge piping. Anything that's going to burst the water lines is going to break your charge piping too. Finding a suitable location for a radiator in the rear of this car is no trifling matter either.

Not to say rear mount turbos won't work in this car, but they work better and are much more responsive in low-boost, high-displacement, non-intercooled applications.

when i had my MR2 spyder on boost, i ran air-to-water intercooling, including lines that went all the way to the front of the car, bosch water pump, relay, and a cute little heat exchanger. i'm not opposed to running lines forward.

[Sammakko]

Originally Posted by AVOturboworld

You'd then need to build a separate cooling system with it's own radiator and water pump. Hardly cost or space effective.

could be done for around $250..

[kbogarto]

To my knowledge AVO has experienced zero failures of the scavenge pump. Not really a big deal in my opinion. Probably easier than running a separate cooling system.

[Poodles]

I don't know of any OEM's using oil less turbos... That's usually enough for me to steer clear of something.

[xwd]

Originally Posted by kbogarto

To my knowledge AVO has experienced zero failures of the scavenge pump. Not really a big deal in my opinion. Probably easier than running a separate cooling system.

AVO uses a modified Subaru OEM mechanical scavenge pump off the FA20DIT, I would hope it has had no failures. PTuning uses an electric scavenge pump, they are the only ones using one now since Accelerated doesn't really make their undermount kit anymore. Those pumps are rated to run for a long long time and haven't really been an issue.

[WORKS]

Sammakko,

Our Stage 1 and Stage 2 kits may meet your criteria. Both kits locate the turbo just behind the engine block, in the typical EJ25 turbocharger location. This placement also allows for use of a gravity oil drain (no scavenge pump), and keeps piping and plumbing lengths to a minimum.

Our turbo is water-cooled and taps into the stock engine cooling circuit. We haven't seen any cooling system issues, even with track usage and an oil cooler adding additional thermal load. On a related note, our Stage 2 kit uses an air-to-liquid intercooler for charge air cooling - that system uses an independent cooling loop, as it needs to maintain a much lower system temperature to cool charge air.

Hopefully this provides some insight!

[WHITE]

Oiless turbo = why even mount?

[Cross]

I loved mine and why not run it into the stock cooling. I tapped my Prototype STS into the Heater core piping and it worked perfectly.