Hey All,<p>I've been wrestling for quite some time whether to post this information or not because I didn't want to create a scare but I figure I owe it to all of you to disclose this information. Once you read on you understand what I mean about creating a scare.<p>After I installed my K-04 turbo I carefully inspected my K-03. I found a small hairline crack in the hot side of the turbo housing. It had been serving 1.0 bar duty for about 16,000 miles. <p>The *HUGE LOOMING* question is whether or not this crack was a result of 1.0 bar duty or do I simply have a turbo with a defective housing?? I wish I knew the answer.<p>Before jumping up and pointing a crooked finger at a chip vendor remember I've had chips from two different suppliers. The first chip which was in the car for about 4 months had detonation. I'm told detonation causes exhaust gas temps to rise sharply. Did heat stress the housing and cause the crack? I don't know. Has the housing been cracked from day one? I don't know. Triple-k says the K-03 is good for sustained 1.0 bar service which further confuses the issue.<p>I wish I had some answers. I'm going to contact triple-k and see what they think.<p><p>

Don, that's a tough one...<p>I'm curious... what exactly are we looking at on the left and right sides of that rib that has the crack?<p>Tom<br>1.8TQMS Silver/Ecru

On the left is the outlet side of the exhaust turbine and the gizmo on the right is part of the wastegate actuator hardware.<br>

don,<br>it's too bad you can't have that thing magnafluxed for free; it looks more like a scratch than a crack just based on the photo. Regardless, even if it were a scratch (a deep one at that), it's the start of something that could have gone very wrong had you kept it in. I'm assumming you checked the K04 turbine housing before you installed it ?<p>This is a good case for polishing down components before installation. It's not strickly an esthetic thing; it's already been proven that a smooth surface will suffer less stress related failures than a rough one; of course to do such polishing costs money but in the case of a turbocharger, it's a worthwhile investment. Just my $0.02<p>Herman H<p>HermanH<br>

You're on the low pressure, low temperature exhaust side of the turbo (low being relative...b/c of course the exhaust coming in has done work, spinning the turbine, lost pressure & temperature).<p>lemme think about this...under stock conditions, that separator would be "between" the cooler exhaust coming from turbine & hotter exhaust coming from wastegate.<p>Going to higher pressure means wastegate opens later...both sides of that separator will be hotter. <p>Dunno...stress cracks would show up from (1) heat-cool cycle stress or (2) increased mechanical stress. KKK says 1bar sustained use should eliminate mechanical stress...<p>But detonation from lean mixture means extremely hot exhaust...that's my temporary guess...<p>Ugh, that means detonation is doubly bad for turbo'd engines...never thought of it that way.<br>steve

Lucas and others (w/ K04 upgrade) to check their K03 turbos....<p>Cris

Well from what I've seen on MR2 turbos and the Eclipse turbos (both small in stock form and run hot when pushed to the upper ends of boost).. It was pretty common to see after around 20k or so of hard driving (we were constantly swapping turbos in the search for big power ehhehe yes we were deviant little bastards) the factory turbine housing had hairline cracks around the wastegate discharge area.. Bottom line.. heat from high turbine backpressure and at time lean running mixtures.. More or less if EGTs exceed 1400 degF(mesured right after the turbine) on a constant basis we knew what to expect from the factory turbos.. now the KO3 is tiny.. the MR2 turbo and early eclipse turbos were good to 250-275.... Thus if one were to have a relatively free flowing exhaust perhaps EGT's would cool a bit and maybe preserve the stock turbine house.. Only real way to tell is stick an EGT on the car and see what it runs.. this will tell you how much heat the turbine housing is having to deal with.. The eclipse unit is a Mitsubishi and the MR2 uses a Hitachi unit.. Also have see hairlines on boosted stock 300ZX turbos (84-95) when running high EGT's for alot of miles.. I'll tell you if you mearsure the turbine back pressure you will be surprised! seeing 2:1 - 5:1 boost to exhaust back pressure in the manifold.. For example did some mearsuing on a 11 sec supra 87 .. runing 1:1 boost to exhaust manifold pressure.. Even heard of some tuners finding combinations of compressors/turbines/(a/r) to get like .8 or .9 to 1 .. have not seen it myself...<p>Anyone Yank the cat's off of their A4 and modded the chip so ODB-II does not scream!?

Weird, I wonder what all the reddish residue is then? Usually octane booster leaves that residue all over your spark plugs etc etc (shrug). I was just guessing :)<p>Brad

Thanks for the picture,<p>It's a beaut. The red is from gasoline additives, check your plug insulators, they'll be tinged too. Normal nowadays.<p>The crack is fine, the web is non-structural. I had a similar effect on a 323gtx and it never propagated further. The old one was actually in a hotter zone because of the poor wastegate design (compared to Audi/kkk). I would worry a lot more if the crack was next to the turbine or the valve exit.<p>Can you answer if the 04 is a larger internal diameter or a different blade design??<p>Thanks

Erik,<p>In case Don doesn't get to your question here is the link to his write-up on the install.<p>Sean<br>97 1.8Tqm<ul><li><a href="http://www.fortunecity.com/silverstone/chicane/175/info/turbo/turbo.htm">K04 Install Information</a></li></ul>

nt<br>

Do you use any?