This also happened to me once on the street but I never found the problem, I thought it was something under the dash.

Can I assume these cable melting events happen primarily near the exhaust parts, or are they more randomly distributed? Looks like I get to add more thermo sleeve to my shopping list, bonus for more under-hood bling.

On my friend's car, the cable did not melt, but it did bind up pretty well. We dissected the failed cable and determined that the outer housing had warped enough to bind the inner cable in the region closest to the turbo housing/exhaust manifold. Insulating the throttle cable from heat coming off those units would be a good start on a solution.

Interesting post on the MotoIQ blog about Sierra Sierra having turbo stud failures.

http://www.motoiq.com/magazine_artic...fr-turbos.aspx

Indeed, those exhaust housings look completely mutilated.

Those T04 housings are made of pot metal. It's no wonder they're pitching turbine wheels.

Its too bad that Sierra Sierra is a budget team and can't afford V-bands.

edit: I'm getting a real kick out of $sierra $ierra dealing problems that peasants on this board solved a long time ago. We really are great. The 3rd paragraph reads like my life with the old set-up.

Look at this safety wire job

Notice which side of the top bolt the wire lies.

Whoa. Is this with an FM stroked/bored/honed and assembled block?

Yep. And Vent to atmosphere on the valve cover and oil pan doesn’t change it I don’t get excessive blow by in the vent system anyway. Motor still shows good compression. Install stock internaled motor keep everything else the same including boost level and problem goes away. Just had to back the fuel down a bit it and it makes slightly less power and torque.

Bob

That's because the'd rather run a twin-scroll exhaust housing and manifold.

In my mind, the only thing that explains this is ring flutter. Have you or FM checked with the piston manufacturer on what you're experiencing?

...and look how well that's working out for them.

The new pistons I got are compleatly different design and also have longer skirts. We will see. I got two more weekends then things start coming apart again.

Bob

...and look how well it worked out for you. It got you to a better solution. I'm surprised you are making comments about the evolutionary process of building a reliable race car.

Twin-scroll has obvious benefits in this application.

Yes; its quite strange but this is also a space-car and nothing like my peasant heap. I learned a lot from looking through a bunch of cars at RLTA last year and incorporated the ideas I could afford into mine.

Pretty common sentiment. Bring spares, tools, cash, and friends if you boost a lot.

The link from the Sierra Sierra blog deserves to go in here:
http://www.cogneusa.com/img/prodotti/steel6a_eng.gif

Several of us managed to anticipate weak spots and been successful with reliable turbo cars. Its not easy, take money, and takes extreme attention to detail.

With whose pistons did you rebuild it? Does it do away with the gas port thingy that may have contributed to your problem?

Wiseco redesigned the pistons for the stroker. They still have gas ports but less of them, 6 instead of 10. They also have longer skirts and a different shape to the structure underneath so they look quite different. They also come with ceramic coating on the top now.

edit: I'll add that they are not compatable with the stock oil squirters.

Bob