Is my 3B intercooler project a failure? (1 Viewer)

[gerg]

That looks great. Any conflicts with your grill or lights? It's pretty tight there.

 

[rossg]

Everything just fits so far.....

I have a cast aluminum elbow for intake manifold. ..

Question

A) recommend a hump hose on the last join for vibration?
B) rufus can you explain the side effect of reverseressure wave?

 

[gerg]

Because the 3b has a throttle plate you can cause a surge if you suddenly let off the pedal when your turbo is boosting hard. The turbo keeps boosting and the charge air hits the throttle plate and sends a powerful wave back towards the turbo that impacts the compressor. Very damaging. If you hear it, it sounds like a weird chugging sound. This is the reason for blow off valves. When you let off throttle, the blow off valve vents the intake pressure to atmosphere and prevents the surge wave from forming. It also allows the turbo to remain spinning really fast and it will boost faster the next time you hit the gas, in the next second or so. The surge wave slows the compressor rapidly. Under normal operation the blow off valve remains closed and you loose no pressure. I've ran many a turbo without a blow off valve, but I am somewhat mindful of how I make use of the throttle. I've only heard it once or twice. It's really only happened when I've let off the throttle completely. At even a little part throttle I've never heard it. That isn't to say it's not present mind you, but I've also never had any compressor damage.

Most gas cars that use it do so for very fast hard shifts where they want rpms to drop as quick as possible and the turbo to boost as fast as possible for racing and stuff. My shifts probably take 3-4 times as long to complete so I suspect that is enough of a difference to avoid it.

 

[RufusTheDufus]

You get a reverse pressure wave every time the throttle closes. The ones you hear are the damaging ones. The turbo pumps a mass of fluid (air) that has momentum. When the throttle plate closes the pressure on the turbo side of the plate raises quickly since there's a slight delay in the opening of the waste gate. My only concern was that a silicone 90 degree elbow being the first connection upstream of the throttle would take the brunt of this pressure buildup and eventually fatigue, split and start leaking. Nothing too damaging, just annoying.

Also, because of the throttle plate, you should make sure the boost signal source is upstream of the throttle. If you measure boost downstream of the throttle on the intake manifold the turbo will spend some time working against the closed throttle. It's common to move the waste gate boost source after the intercooler to make up for any pressure drop.

 

[rossg]

Finished today....
Looks like i get about 1psi drop across intercooler which is much better than before....

For anyone interested i used a 75degree bend out of intercooler cold side. I found this the besg way to navigate around headlight. I used another 75degree to bend past battery and on to cast aluminum elbow.

both bends on hot side are 90degree. Pipe clears shock tower by 5mm...

Thanks all for your inputs...

 

[KevsDieselLC]

Hey guys, just finished my intercooler project on my 3B. Was a fun project and I am definitely getting 10-15% more power. So worth it for hitting the mountains. Let me know if you have any questions.

Intercooler installed

• KevsDieselLC
• Feb 5, 2017

Intercooler

• KevsDieselLC
• Feb 5, 2017

 

[RufusTheDufus]

I have a question, do you have a fan shroud for your radiator?

 

[Tin basher]

I would try to lose that j bend coming right out of the turbo
It looks like you could rotate the blue coupler 90 deg
Towards front of truck and come almost straight into it from your blow off valve
You could also clock the compressor housing
So it points down or to the side if you need to clear ps pump
Every turn cost you flow and pressure

 

[KevsDieselLC]

I have a question, do you have a fan shroud for your radiator?

I do, just took it off temporarily to have more space in there. Even without it the engine hasn't been running hot really.

 

[KevsDieselLC]

I would try to lose that j bend coming right out of the turbo
It looks like you could rotate the blue coupler 90 deg
Towards front of truck and come almost straight into it from your blow off valve
You could also clock the compressor housing
So it points down or to the side if you need to clear ps pump
Every turn cost you flow and pressure

Yeah, good point but I get really close to power steering pump reservoir and I thought I needed to intall the BOV that came in the kit (which I found out by reading in the forum that most people don't think so). So, I'll eventually remove the BOV and the T-coupler that comes with it and run the pipe straight forward.

 

[Tin basher]

You already have the blow off valve it's not going to hurt anything by running it
Personally I feel anything with a throttle plate should have one
More benifits to running a bov than not
Biggest is it protects against compressor surge
That could destroy your turbo
And shrapnel from turbo can make it into your engine

 

[KevsDieselLC]

You already have the blow off valve it's not going to hurt anything by running it
Personally I feel anything with a throttle plate should have one
More benifits to running a bov than not
Biggest is it protects against compressor surge
That could destroy your turbo
And shrapnel from turbo can make it into your engine

Thanks, Tin basher. I appreciate the advice. While we're at it: can you tell me where to run the vacuum line too? Also, do I need to screw something onto the big outlet (it has a thread on it which made me wonder). Thanks a bunch!

 

[Tin basher]

The big threaded port I'm assuming
Is the dump you could freed it back into your air filter to silence it or not worry about it
The vacuums line should go to a fitting on the engine side of the throttle plate

 

[KevsDieselLC]

The big threaded port I'm assuming
Is the dump you could freed it back into your air filter to silence it or not worry about it
The vacuums line should go to a fitting on the engine side of the throttle plate

Thanks man! Much appreciated!