Latest Project - Headers

[Reaper930]

Yeah - or WHITE hot headers...my next set will be inconel...

[A930Rocket]

No damage to the engine so far after several thousand miles. I was just driving the car with no boost to break it in. Brand new GHL headers and I think that running the timing retarded (my mistake) made them hot enough to dislodge something. Never did see anything that caused it, but Kevin at Ultimate said it was FOD. No way there was a nut or anything in the headers. We turned that engine over many times working on it and would have heard/seen something.

I would suggest everyone use a USED turbo when breaking in an engine/headers for this very reason.

[Miguel Antonett]

Was that before or after Turbopalooza? Because that engine sounded pretty good at the track...

[JFairman]

Originally Posted by A930Rocket

I can tell you what happens when you get FOD in a new turbo on a new engine with new headers (25 miles)...

What didn't help was that I had my timing off and had it retarded. Headers got hot, very hot and probably dislodged a piece of metal.

It looks like the shaft broke in this picture. The turbine wheel is off center and touching the turbine housing where it's wet with oil. If the shaft was bent then the blades wouldn't all be bent over the same way.

The damage to all the turbine blades looks like it came from high speed rotational contact with the inside of the turbine housing after the shaft may have broken while it was spinning real fast.

Not saying it wasn't welding slag that broke that turbo, but whatever bent those blades was stationary while the turbine was spinning.

This failure could also be the result of an oversize Holset compressor wheel that was installed on a modified shaft that was not designed for the weight and thrust forces of the bigger compressor wheel in a small bearing housing that also was not designed for the larger and heavier Holset compressor wheel.

Also, if the completely assembeled hybrid turbo with larger compressor wheel is not electronically balanced at speeds between 100,000-200,000 rpms > being spooled up to those speeds with air pressure in a VSR turbo balancing machine.. then any possible second and third order high speed harmonic vibrations of the shaft from a very slight imbalance can destroy the shaft and bearings and piston ring oil seals in a short time.
Add to that the excessive heat in the exhaust from retarded ignition timing and the damage can occur faster.

Just mentioning another possiblity of what happend there... the builder of these hybrid turbos will always look for excuses and always puts the blame on the customer.

[mb911]

Originally Posted by A930Rocket

No damage to the engine so far after several thousand miles. I was just driving the car with no boost to break it in. Brand new GHL headers and I think that running the timing retarded (my mistake) made them hot enough to dislodge something. Never did see anything that caused it, but Kevin at Ultimate said it was FOD. No way there was a nut or anything in the headers. We turned that engine over many times working on it and would have heard/seen something.

I would suggest everyone use a USED turbo when breaking in an engine/headers for this very reason.

I would highly suspect that the headers were Not back purged thus causing the metal dislodging. If properly purged the weld on the inside looks just like the outside and there is no seem at all for slag. . But always a good idea to run a used turbo I suppose to protect your investment

[RarlyL8]

I give this same advice to folks who are rebuilding their engines and installing a new turbo as part of that build. Assembly gunk will be in the oil and headers are new so it is insurance to run an old turbo until the first oil change.

FOD could easily bust a turbine shaft. We all know you have a hard on for UMW Jim. Many things are strapped on a 930 engine that were not designed to be (such as a water cooled turbo). There have been thousands of K27 turbochargers sold and used on the 930 in the last decade or so. If they were so bad you would have seen a MM type thread on them long ago. **** happens, we are trying to help folks avoid some of it by understanding the welding process and how going cheap can cause harm.

[stup]

"going cheap can cause harm"

Not saying this was the reason for the above shown case.. but not closely inspecting anything you fit to an engine can cause harm!!,,whether it has a Porsche premium or not!

Going cheaper can be a success also!

When were GHL headers cheap??.,like the ones mentioned above that were fitted..

"Going expensive,cheap or whatever can cause harm",,everything fitted should be inspected prior to installation!

[mb911]

Originally Posted by stup

"going cheap can cause harm"

Not saying this was the reason for the above shown case.. but not closely inspecting anything you fit to an engine can cause harm!!,,whether it has a Porsche premium or not!

Going cheaper can be a success also!

When were GHL headers cheap??.,like the ones mentioned above that were fitted..

They never really were but corners were cut and that is probably why they are out of business. just a guess

[JFairman]

"There have been thousands of K27 turbochargers sold and used on the 930 in the last decade or so. If they were so bad you would have seen a MM type thread on them long ago."

Hi Brian
The way you worded that made it sound like I'm putting down K27 turbochargers in general.
That is not what I said and thats not the case... The origonal 3K turbos are engineered, assembled, and high speed balanced very well and have been reliable for a long time. You get what you pay for with them.

That said, I'm not going to repeat what I said above... and I have more details about the turbos I was referring to that I have not made public.

There's a bunch of other guys out there with the same experiences I have had with them.
I have just under $3000 into an HFS turbo that I have only put approximately 2000 miles on. Thats origonal price plus 2 rebuilds in 2000 miles.

That experience combined with the attitude of the builder left me and others disgusted with them, and I have to say I'm pissed off.

[RarlyL8]

Jim, sorry for the bad experience. I am refering to the UMW turbos in the previous post, not K27 turbos in general. Many sold over the last decade or so with few problems. There have been a few well publicised failures of late and I have paid attention to that. The above picture is a perfect example of the difficulty of diagnossis. Multiple failures with the same customer are outside the norm and create a difficult situation for both involved.

[billjam]

Meanwhile, back to Rarly's headers ...

Brian, where do you plan to put the O2 sensor?
This could start a whole new hijack!

[spence88mph]

Don't you want that after the turbo? My rarelyl8 zork and muffler have bungs for 02 sensors.

Great project BTW Brian... I didn't expect anything but though from you. Are you leaving on the exhaust springs? I have these on my moto and they're a PITA when they break, always think I'm going to take out an eye when stretching new ones on!

[mb911]

Originally Posted by spence88mph

Don't you want that after the turbo? My rarelyl8 zork and muffler have bungs for 02 sensors.

Great project BTW Brian... I didn't expect anything but though from you. Are you leaving on the exhaust springs? I have these on my moto and they're a PITA when they break, always think I'm going to take out an eye when stretching new ones on!

I set the springs up pretty lightly so they should not be an issue compared to some of the stuff you see

[DonE]

Originally Posted by mb911

I would highly suspect that the headers were Not back purged thus causing the metal dislodging. If properly purged the weld on the inside looks just like the outside and there is no seem at all for slag. . But always a good idea to run a used turbo I suppose to protect your investment

I don't think there are too many of us out there who have used turbos (and in working order) to break in a new motor. Not to say its not ideal, but this thread (and forum) are the only places I've heard of, that recommend using a used turbo. Personally, I've put three new headers on my car with no problems, and I've built at least a dozen more the same way. Again, it would probably be ideal, but for most of us, its not practical. And maybe I've just been lucky...

[A930Rocket]

Sorry for the hijack Brian.

This happened about Nov 2006. I've only driven the car about 1500 miles max since then.

Originally Posted by Miguel Antonett

Was that before or after Turbopalooza? Because that engine sounded pretty good at the track...

Here's a picture before the install. Still looks and runs great.

[gsmith660]

Originally Posted by A930Rocket

Sorry for the hijack Brian.

This happened about Nov 2006. I've only driven the car about 1500 miles max since then.



Here's a picture before the install. Still looks and runs great.

I hope to have one of those someday when my motor grows up

[mb911]

Originally Posted by DonE

I don't think there are too many of us out there who have used turbos (and in working order) to break in a new motor. Not to say its not ideal, but this thread (and forum) are the only places I've heard of, that recommend using a used turbo. Personally, I've put three new headers on my car with no problems, and I've built at least a dozen more the same way. Again, it would probably be ideal, but for most of us, its not practical. And maybe I've just been lucky...

I agree with you on that and to be honest I never had used a used turbo though its not a bad idea. Hey Don did you get my reply on the email?

[DonE]

Originally Posted by mb911

I agree with you on that and to be honest I never had used a used turbo though its not a bad idea. Hey Don did you get my reply on the email?

Sure did - thanks very much.

[911st]

Seems like we are talking about a low probability event and we can not even be 100% sure that the failures represented were from the an inferior weld.

A flaw in the turbo build or turbo prelubing issue could cause a bearing failure that could have the same potential for failure as could a turbo stall issue and such failure might not look much different.

Even if that was the reason, it seem to happen to high end aftermarket headers as often as not.

No mater, we are still looking at a great and worthwhile project that has solid potential.

Not much point in trying to scare us away from lower cost imports.

[djdawson2]

Interesting secondary thread. While I can't make direct Porsche commentary, I can certainly make turbo commentary. I've spent many many hours testing numerous configurations of Audi engines involving different headers and turbos... all of which I built. It might amaze you that my favorite header for my Audi application is built from heavy gauge "weld ells" that are mild steel. The header is swain coated and has been 100% trouble free for over 70k miles of abuse in an engine producing about 450hp at 4 wheels. I have seen it cherry red on many occasions.

That being said, a number of Audi enthusiasts, including myself, suffered Bosch spark plug failures in high output engines. The failures amounted to dropping the electrode post into the cylinder and spitting it out through the exhaust valve, and eventually through the turbo. To me, this is certainly the equivalent of FOD at or beyond what you might see from welding debris. Every instance caused some sort of turbine wheel damage, but not typically extensive. Either there would be a small "ding" or a larger chip missing from a *single* turbine blade.

The pictures I've seen in this thread don't look like FOD to me, but major turbo failure. Which brings up the next subject... the origins of your turbo.

In my experience, I would not recommend turbos that were either built or modified by the aftermarket, unless you REALLY know the builder. Every engine I have built/run utilized a turbo built at the factory (Garrett or KKK for me). I have witnessed literally dozens of my fellow enthusiasts experience turbo failures from minor to major... each one coming from various "tuner" shops either as special builds or unique hybrids. I have not experienced a single failure with factory built units, both from KKK and Garrett. I don't believe this to be coincidental. Building a turbo is not child's play... and there are a ton of aftermarket shops building their own turbos using garbage components and assembled poorly.

IMO, buy from the source. I've had a bunch of Audis with hundreds of thousands of miles on them still running the original KKK turbo. I can't say I've seen the same with aftermarket stuff.

Dave