Blew my int piping again yesterday on the interstate, then 5-mins later my temp-gauge went about 3/4 of the way to hot.

Why did i over-heat? because i blew my pipe?

 

did the pipe blow right in from of the radiator? if so you were probably spewing hot air right into the radiator, its kinda hard to cool a car with hot air

 

It was the pipe that goes from the compressor-side to the intercooler

 

You probably have another problem, I've driving probably over 200 miles with my inter cooler pipe blown off.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by StolenTeg &raquo;</TD></TR><TR><TD CLASS="quote">You probably have another problem, I've driving probably over 200 miles with my inter cooler pipe blown off.

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That's a really bad idea since you probably overspun the hell out of that turbo.

 

Well if it blow off while im far away from home and have no tools with me then i wouldnt be getting on it...

I dont think it would be a problem as long as you drive like a sane person, i mean i've done it and the turbo is fine.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by StolenTeg &raquo;</TD></TR><TR><TD CLASS="quote">Well if it blow off while im far away from home and have no tools with me then i wouldnt be getting on it...

I dont think it would be a problem as long as you drive like a sane person, i mean i've done it and the turbo is fine. </TD></TR></TABLE>


poor poor overspun turbo

 

I drove it nicely all the way home. i fixed the pipe & it runs fine.

 

This might be kinda a noob question, but why would having the charge pipe to the intercooler off over spool the turbo? Wouldn't the wastegate still hold boost and keep the turbo from spooling off the chart? It seems like you would just be venting hot compressed air to the atmosphere.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bungalo101 &raquo;</TD></TR><TR><TD CLASS="quote">This might be kinda a noob question, but why would having the charge pipe to the intercooler off over spool the turbo? Wouldn't the wastegate still hold boost and keep the turbo from spooling off the chart? It seems like you would just be venting hot compressed air to the atmosphere.
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Because the WG uses boost reference to open the gate when the desired PSI is achieved, without that reference/boost source, the gate stays shut and the turbo spins to infinity.

 

Ok, I can definitely see that being a problem if your vacuum connection is after the charge pipe leak. Would you have the same effect if your vacuum line was connected to a tapped fitting on the turbo? Maybe I'm just confused about the way the vacuum source works... Does it have to essentially be a closed loop to work?

I'm curious because to pass emissions unfortunately I have to convert back to OBD2. I was banking on being able to disconnect part of my charge piping, vent the boost to atmosphere, while keeping the turbo from spooling to oblivion, and essentially run N/A with a filter on the intake piping (adjusting injectors accordingly back to stock).

Anyway, thanks for clearing things up!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bungalo101 &raquo;</TD></TR><TR><TD CLASS="quote">Ok, I can definitely see that being a problem if your vacuum connection is after the charge pipe leak. Would you have the same effect if your vacuum line was connected to a tapped fitting on the turbo? Maybe I'm just confused about the way the vacuum source works... Does it have to essentially be a closed loop to work?

I'm curious because to pass emissions unfortunately I have to convert back to OBD2. I was banking on being able to disconnect part of my charge piping, vent the boost to atmosphere, while keeping the turbo from spooling to oblivion, and essentially run N/A with a filter on the intake piping (adjusting injectors accordingly back to stock).


Anyway, thanks for clearing things up! </TD></TR></TABLE>

It doesnt matter where it sources the pressure from, there will be no pressure if a pipe is off....... think about it for a second.

Why pull your charge pipe to go through emissions? It should run the same with the pipe on or off, as long as the stock injectors, map and your factory 02 is hooked up you shouldnt have an issue. I am in the same dilemna as you, I plan to just add a cat and leave all my turbo stuff on and go through the lanes, as long as you have no CEL and a Cat on the car you should be ok.

 

If any part of your charge piping is off/disconnected, your MAP sensor (and wastegate line) see zero boost. That keeps the WG closed w/all exhaust spooling the turbine, and the compressor has nothing to build pressure against. The freewheeling shaft eventually hits speeds in far excess of what it was designed for.

To go NA with the turbo still on, you want to remove the spring from your WG (let the exhaust pressure push the valve open), and remove a clamp from a coupler or two. That way if any pressure does build from boost creep, it goes out through the unsecured coupler. Just don't intentially give it too much throttle - only baby it around.

 

I understand the boost problem now. When venting to atmosphere you have no pressure! (above atmospheric). Sorry, it's been a long day, and simple physics has escaped me

I had originally thought about the wastegate spring idea as well. But will a 38mm Wastegate be able to dump/handle all of the exhaust gases? I was afraid that would require a really large wastegate. Hence the point of running a 44/50/60mm wastegate to support high/low boost without having boost creep.

Again, thanks for the info! I'm new to the boosted world and am piecing together my first build as we speak.