My 2LTE is an alcoholic

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raboyto2 said:
Ideally for pre turbo setups you want something like this.

If you want to get more technical about it (lots of math and equations coming up) then this is a fantastic read about pre turbo water injection.

http://killerbeeperformance.com/download/ifog/i-fog.pdf
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Thanks raboyto2. I'll have a read through that document; looks really good.

One other thing I noted while driving on the highway to the airport this morning is that I gain about 2psi with the system on versus not on. Might be the pre-turbo nozzle? Will have to read/experiment more before I really know.
 
GTSSportCoupe said:
Thanks raboyto2. I'll have a read through that document; looks really good.

One other thing I noted while driving on the highway to the airport this morning is that I gain about 2psi with the system on versus not on. Might be the pre-turbo nozzle? Will have to read/experiment more before I really know.
Click to expand...

I've read that the pre-turbo nozzle shifts the turbo in the efficiency map such that it acts like a bigger unit (able to push more boost at lower temp levels), possible that's what you're seeing with the system on?
 
IanB said:
I've read that the pre-turbo nozzle shifts the turbo in the efficiency map such that it acts like a bigger unit (able to push more boost at lower temp levels), possible that's what you're seeing with the system on?
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Yeah, I think you are probably right. In that case, there is some benefit for me with the pre-turbo.

Gonna pull the intake off and have a careful look at the compressor again today and see how it's doing.
 
IanB said:
I've read that the pre-turbo nozzle shifts the turbo in the efficiency map such that it acts like a bigger unit (able to push more boost at lower temp levels), possible that's what you're seeing with the system on?
Click to expand...

Yeah sorry but that's complete rubbish.
 
So I inspected the compressor yesterday. Maybe it was just my imagination, but I thought I could see the beginning ever so slightly of compressor erosion. So I decided to scrap the pre turbo nozzle. Went for a drive after, and am missing some of the sweet pull that it used to have, as well as the extra boost. So I am a believer in the pre-turbo nozzle concept. Just need a fancy nozzle setup to preven erosion I guess. Maybe I'll build one like in the picture above when I get some time.
 
I think your wise to forgo the pre compressor injection as it would be on your mind all the time as to if its damaging it or how long its going to last etc.... The odds are against you in that set up.

Have you considered injecting into the exhaust stream? B52s do it for take off to increase the density of their exhaust for greater thrust just for take off. The nozzels would have be pretty tuff and spaced out of the stream though. One of the many ideas id like to toy with when I retire in 50 yrs.
 
gerg said:
Have you considered injecting into the exhaust stream? B52s do it for take off to increase the density of their exhaust for greater thrust just for take off. The nozzels would have be pretty tuff and spaced out of the stream though. One of the many ideas id like to toy with when I retire in 50 yrs.
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That is one of the smartest ideas I've heard in a long time. Would greatly reduce exhaust back pressure, which would help turbine efficiency. Injection in the dump pump would probably have the greatest impact. Would need a stainless exhaust though, or would have corrosion issues pretty quickly I imagine. Hmmm...you've got me thinking now.... :wrench:

You are right; its nice not having to worry about the compressor now that I've removed the pre-turbo water injection.
 
Hmm im not sure how it would affect back pressure, but I believe it would either provide more energy for the turbine, or allow the turbine to extract more energy from the exhaust gas. In any case it is bennifical for jet turbines. Ive not seen it demonstrated on a turbocharger though. Both devices extract energy in the same way so I think it would have a similar affect. I cannot take credit for this idea as im sure it has been done multiple times before. Ive just never seen it demonstrated on a turbo engine.
 
By cooling the exhaust it is made more dense, thus reducing back pressure? Turbine operating with less back pressure (higher pressure ratio) could do more work? I'm sure there is lots more to it. I'm going to read up on it when I get a chance.
 
GTSSportCoupe said:
By cooling the exhaust it is made more dense, thus reducing back pressure? Turbine operating with less back pressure (higher pressure ratio) could do more work? I'm sure there is lots more to it. I'm going to read up on it when I get a chance.
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Wrong way around. Cooling and shrinking the exhuast will stop your turbine working. Gergs steam turbine idea is to increase the exhaust volume and hence pressure through steam.
I'm not sure what the overall result will be. It depends on where you end up with pressure gain vs heat loss.
 
I think I see what you and Gerg are saying now...you mean inject pre-turbine?

I was thinking injecting post turbine to reduce exhaust back pressure by cooling the exhaust gasses.
 
GTSSportCoupe said:
I think I see what you and Gerg are saying now...you mean inject pre-turbine?

I was thinking injecting post turbine to reduce exhaust back pressure by cooling the exhaust gasses.
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Injecting into the exhaust is only good for playing steam train. If you have a backpressure problem there then just fit a bigger exhaust.
 
gerg said:
Steam train sounds pretty cool.
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It's over-rated. I have a 300tdi steam-train. Previous owner drove almost 2000km with no radiator cap so the head is cracked. He also turned up the pump.
Get it warm and it blows white steam out the exhaust. Put your foot down and white steam mixes with black smoke.
 
Dougal said:
It's over-rated. I have a 300tdi steam-train. Previous owner drove almost 2000km with no radiator cap so the head is cracked. He also turned up the pump.
Get it warm and it blows white steam out the exhaust. Put your foot down and white steam mixes with black smoke.
Click to expand...


Steam train, meet coal train.
 
yotahed said:
How the meth addiction GTS?
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Sort of a funny story. I've been doing a lot of towing in the hot weather we've been having over the past couple months and was looking forward to the benefit from the meth system. However it seemed to have no effect recently, and I was running out of fluid in about 5-10min! I was ready to rip the system out and sell it, until I discovered meth fluid all over the top of my engine one day. I then discovered a hole had burst in the hose! I put a new hose in, and turned the pump pressure down a bunch, and am back in business! It's a 250psi pump, but had been turned up to 300psi. The hose was only rated to 250psi, so go figure.

Anyhow, yeah, turned the pressure down to probably 100-150psi, so my fluid lasts WAY longer now. Not nearly the power available, but it definitely does have a decent cooling effect. I just got back from a trip to the interior this weekend (not towing mind you). We were traveling in 32-38C weather the whole way (highway 3 primarily, so a few good summits). I used the meth system only on the big hills. It dropped EGTs by about 100F, and definitely gave some extra power. Even loaded up to probably 5800lbs GVW I could maintain 90km/h up every incline, even that steep one going West from Princeton past that big mine there (not sure if you know the one).

Glad I modded my cooling fan before that trip too, as it was pretty darn hot and I was running the truck hard. Might still blow-up that little engine one day...
 
Those are nice roads. Glad the results are really paying off.
 
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