Thread: turbo for 4bd1, who,what where ??

I'll second that, after the gasses leave the exhaust valves they begin to loose their 'usefullness' to drive a turbocharger turbine as they loose velocity and heat almost immediately. The quicker they encounter a turbine and expend their energy the better. UNLESS the ducting between the manifold and the remote turbocharger can be shaped to retain gas velocity, and insulated to reduce heat losses, then I can't see any advantage other than for a space point of view.

My 2.75c.

JC

So what are the advantages of a remote mount ???

What are the disadvantages ??? Anyone know the realistic costs involved ??

Will it make the County pull up hills without slowing down 15-20kmh and can the air con unit be kept with a remote set up ??

Originally Posted by jerryd

So what are the advantages of a remote mount ???

What are the disadvantages ??? Anyone know the realistic costs involved ??

Will it make the County pull up hills without slowing down 15-20kmh and can the air con unit be kept with a remote set up ??

Yes, you can keep the air con - nothing is changed on the LH side of the engine other than the exhaust being re-routed behind the engine over to turbo on the drivers side.
That would be the only advantage I could see (maybe apart from not having to buy a turbo exhaust manifold).

Disadvantages as I see them:
- the drivers side of the engine bay is very full with the turbo and plumbing.
- would be harder to fit an intercooler than with a conventional setup

Steve

Originally Posted by Dougal

Simply, turbos feed off exhaust heat, pressure and pulses.
The futher away the turbo is from the ports, the less heat and pulse strength there is.

What are the advantages of remote mount? Besides packaging for some vehicles I can't see any.

basically correct BUT, a remote mount gives the advantages of being able to tune you manifold, thus getting the pulses in line rather than have them argue as is the case with the current manifold. Remember EGR temps is an average. Two or more pulses arriving at the same junction at the same time will push the temps much higher, say 200-300 deg. as the pressure / density increases. It would also remove the go fast go slow effect on the turbo ( a bit like torque pulses on the gearbox).
Even just moving the turbo a bit further away with the original manifold will have the effect of smoothing out the shockwave fronts.

Having that sorted means that your back pressures will drop which leads to better evacuation of your combustion chamber and that can only be a plus.
The first noticeable difference would be lower egts for the same fueling/ air. Thus more fuel could be added.

As for a pressure drop, yes but this is minuscule and more of a result of reducing back pressure / increasing volume before the choke point of the turbo. There is also the parasitic resistance, but this is minimal as well.
Anyway with a any temp drop or velocity drop is a non issue because there is a corresponding increase in density. Mass X velocity is what spins the wheel not temperature.

There was a comment posted some where on this forum that because the manufactures don’t then its not worth doing. The reality is that manufactures are concerned with cost and there fore have stuck with cast manifolds. Look at a TD5 manifold which an attempt and the responding problems that that has created with the casting cracking. Compare that to a 300 tdi with its slip and slide manifold which gives no problems. And if there are no advantages why is there a benefit to fitting the nicer 200 tdi manifold to 300 tdis.

I found some pictures. one is for a Subaru, not really what we want to see but is demonstrates how far you can move the turbo and that closer is NOT better.

one of the mechanics at work has a SS ute with a remote mount turbo that lives behind the LHR wheel.... saying it goes like a cut cat is an understatement

Originally Posted by clean32

[COLOR=black][FONT=Verdana]basically correct BUT, a remote mount gives the advantages of being able to tune you manifold, thus getting the pulses in line rather than have them argue as is the case with the current manifold.

That's nothing to do with remote mount. That's about the manifold design. Remote mount uses the NA manifold which is not a pulse converter type.

There are two different types of turbo manifolds. Pulse tuned and minimum volume. The IHI manifold was a pulse tuned 4-2, the later garrett manifold is minimum volume type.
It's worth noting that all modern tdi engines are using minimum volume manifolds, right up to the 200kw/600Nm 3 litre mercedes which runs 42psi boost.
These engines beat everything prior for economy, response and power. Case closed really.

Originally Posted by Dougal

That's nothing to do with remote mount. That's about the manifold design. Remote mount uses the NA manifold which is not a pulse converter type.

There are two different types of turbo manifolds. Pulse tuned and minimum volume. The IHI manifold was a pulse tuned 4-2, the later garrett manifold is minimum volume type.
It's worth noting that all modern tdi engines are using minimum volume manifolds, right up to the 200kw/600Nm 3 litre mercedes which runs 42psi boost.
These engines beat everything prior for economy, response and power. Case closed really.

in power, this can

The first picture is a compound set in what appears to be a marine engine. Completely different application.

The second picture is the larger turbo in a compound set. The smaller turbo will be mounted in close where it should be, but it's on the other side of the engine, hidden from the camera.