Race Ware Nuts Backing Off???

[JTO]

Hi All,

I need someone like Wayne or John W to confirm what was told to me about my engine Friday. Keep in mind this engine was fully rebuilt with TImecerts, ARP hardware, etc. I had Stuttgart in Portland examine my cylinder head studs for torque due to some light oil leaking at the case/cylinder junction. They indeed found a few of the driver's side nuts at around 16 f-lbs, indicating loss of torque. They said that there was no indication of head studs pulling upon their examination. They said that there have been several occurences of Race Ware and ARP nuts coming lose. The nuts were retorqued to spec. They suggested that if upon rechecking the torques in a couple of thousand mile they are lose again, change to the Porsche nuts and washers.

Has anyone heard of this happening; the nuts backing off? Stuttgart has a good reputation among the Portland Pelicans and the PCA. I need someone to call BS for me. John? Wayne?

Thanks you,
Troy

[JTO]

For those who care, it appears that the nuts backing off Raceware and ARP head studs does occur. The thermal expansion rate of the studs does not match the engine well. As the engine thermal cycles, the nuts loosen. The solution provided to me by someone that I trust very much in the Porsche world (Steve Weiner) is to retorque the studs very carefully during each valve adjustment. Ultimate fix, 993 TT studs. These you can torque and they stay that way. I had a good education today.

Troy

[HarryD]

Troy,

So, does this mean that your engine is ok. Did Mike get you going again?

I'm in the middle of rebuilding my Euro 3.2 and was planning on using Raceware head studs as well as Raceware rod bolts.
Will the same thing (backing off) happen with the Raceware rod bolt hardware as well? Also, what nuts should you use with the 993tt head studs?

[JTO]

Hi Harry,

I am confident that Mike will sort out the CIS/ignition issues. I will call them soon. I am very encouraged what Mike said about the nuts backing off was confirmed by Steve W. I hope we are on the road to many fun and trouble-free miles. I'll keep you posted on the final analysis. Good lead though, Harry. Nice shop with good guys.

Mackpipes. I am not an authority on this or any other Porsche related topic. I am striving to learn though. I would highly recommend that you contact a shop that has built many many motors and ask them for their opinion on engine hardware (do a search here for engine rebuilders. A list was recently put together). Steve Weiner recommends Porsche 993 TT dilavar studs and their associated Porsche nuts. Call him at 503 244-0990. He is very generous with his time.

Troy

[Wayne 962]

I answered this in the other forum. Please don't post the *same* question in both places.

-Wayne

[JTO]

Sorry Wayne. The Rebuilding forum was slow today.

Troy

[snowman]

[i]...Will the same thing (backing off) happen with the Raceware rod bolt hardware as well? ... [/B]

Should not happen with rod bolts, as they are tightened to a specific stretch, and the metals are similar, and they are much shorter than head studs, in length, all factors in this problem. You would have heard about it as well from more than slightly tweeked off racers.