Fastest928

Folks,
I am trying to better understand the factory directive to replace all early "narrow" base 968/928 rods.

Has anyone experienced a failure of a 968 rod? If so, under what conditions?

If this has been previously discussed, pls point me in the direction so to not repeat former threads.

Thank you!!!

Marc

DEVEK

Tom Carson

This is covered in Technical Bulletins, Book K, (PNA 000 082E)
Jan 1994 - Dec - 1994 page 11.

For the 968, "as of October 1, 1993, engine #42R0958 - #42R50621"

Included are photos of the replacement conrod that is reinforced in the area of the conrod bolt surface...casting #944 103 111 2R (17.0mm thickness) vs. the original (and pathetic) casting #944 103 111 1R (10.0mm thickness).

Of course, they applied the usual weasel words “If during a repair, one or more rod nuts are loosened, all connecting rods should be replaced”…yada, yada.

Model 4 & 8; Group 1; Part Identifier 1340; Number 9401

Dave in Chicago

Yup, noted in manual like so... I would, sitting here wiwht my early '92 968, be VERY interested in any personal experiences with conrod failures as well.

namasgt

any updates on this for 968s ?

Chaos

TG I have a 94

sergiomartins

I have a 94 too, although i visualy checked the rods when i rebuilt the engine, and they were the correct version.
my feeling is that maybe the manufacturer of the early rods wasnt too reliable regarding the forging and the sintered metal the rods are made of, and porsche changed manufacturer or supplier of the metal ence the revision on the part.
I heard of bent rods on 996 turbo pushing insane numbers, maybe somebody with a 968 turbo conversion can explain better.

namasgt

^^^ Well, I think the same manufacturer made the rods except the 2R rods have been beefed up a little bit compared to the early forged 1R rods. I just want to know if any one has super charged or turbo charged their 968 and end up with a broken rod. I have heard or read that 968s were being super charged by a company in Europe and some end up with broken rods, the company stopped making SC kits for 968s.












9 .

RajDatta

I doubt many that turbocharged their cars, kept the same rods. Turbocharging is a lot more involved and typically not a bolt-on. Supercharging, on the other hands, has mostly been setup for bolt-on.
Also, people tend to get power hungry and start increasing the boost on bolt-on setups, hence testing the factory rods. This is probably what happened with the UK vendor.
Raj

namasgt

I agree with you. But the thing with 1R rods is that they have been known to bend or break on the GTS engines that are naturally aspired, no superchargers or turbos. Porsche screwed up in designing the 1R rods and their trying to cover it by just saying whenever the rod nuts are untightened all the rods need to be changed to 2R.
Any one who is planing on super charging their 968 that has 1R rods may want to reconsider their plans or upgrade to 2R rods IMO.

Rogue_Ant

The area they re-enforced is for tensile loading (RPM), not compressive (torque/hp).


-Rogue

Vilhuer

It is likely first '94 MY engine number were R 00 501 and R 50 501. This means some 97 + 120 engines where made at beginning of '94 MY before rod design was changed.

Jfrahm

I wonder if a borescope up the oil drain could see the rod type?