RCinXS

Putting on the heads today.

84 16 V.

The new Head Gaskets are thinner than the originals. They don't have a Porsche part number. They are Victor Reinz.

Since the WSM references part numbers, I'm not sure what to do.

Also have a silicone bead around the studs, etc.

The first 2 torque stages are similar for either old or new style gasket.

Question is for the final 3rd torque.

Should it be 61 ft.lbs?

Or 65.7 ft.lbs?

Also seems that original had a 4th stage of backing off 1/4 turn and then torque to 61 ft.lbs.

This is not mentioned for the newer gasket type.

Appreciate any input. Don't want to over torque.

928mac

Hello RC;

I believe that Roger once told us that the Victor Reinz are what porsche uses.
Maybe Roger will chime in, incase I am wrong.

I noticed (as far as torqing went) that It depended on the model year (MY) which step procedure that you follow.
Since you have an older year ILL let someone else answer that.

RCinXS

Thanks Brad.

WSM seems to indicate that it's based on the Gasket. It sort of makes sense, since the new gasket is thinner and has the silicone bead, (I'll call it a perimeter bead).

928 International said to go with the later torque number, since it's a newer style gasket.

I'll wait for a bit to see if others chime in who have used the newer, thinner gasket before I do the final torque.

Still wondering on the forth step of backing off 1/4 turn and then redoing the final torque. Might not be required for the thinner gasket.

Herer's a couple of pix.


How goes the TecGT upgrade?

928mac

Thanks for asking.

The Tec-GT wiring is going slow but sure.
I don't have a lot of ambition, .. but this week end I hope to make some major head way
because I had some major break throughs this week
(Lines done, Coils mounted, Most sensors connected.)

2 issues yet are, there are no instructions on the vaccume valve in the front under the oil fill, that leads to the tank fume container and I know there was another but I can not remember.

I was able to get my intake to air filter tube machined on a lath so that it will fit my new K&N snorkal and still work on the factory air box

I really really like the way you polished the ports, they look great.


Back to the gasket.

I had ordered a set of the thick gaskets from a vender which were
suppose to be strong enough for super charging or what ever, incase I decided to do something like that down the road.

When I got them, they did not have the perimeter bead and I did not like the way that they were not a good match to the cylinders.

I compaired them to the victor (which I didn't like as a north american mechanc)
and I found the Victor to be far supirior in quality, even though they were a bit thinner.

I used the victor with the bead and used the stock torques because I was told that is what porsche used when they built it. I used the old torque settings that go with the old motor and the stock gaskets. (no what I mean)

Mine is a 32 V 1989 so I did not have the 4th torque step option. Maybe it was for studs?

RCinXS

Good to hear the TecGT is coming along. I'm going with a Tec3, which is similar.

Like the way you installed the coils.

Would love to see the TecGT install manual for the 928. Probably would have some good insight and I might be able to use to save some time.


The WSM has different torque specs from a certain engine onwards.

See attached WSM pages. My engine is 28/20 so I can believe I use the slightly higher torque numbers. The 1/4 turn release and re torque is what I'm really wondering about now. Could have been for the original, thicker gaskets.

The manual states "new procedure". This tends to make be believe that the backing off and re torque isn't needed.

Howerver, one must remember that the WSM was translated from German to English, and sometimes details are lost in such translations.

Lizard928

The retorquing is more to help with the compression of the gasket.

Do the gasket in stages and before you do the final retorque, leave the engine sit overnight in a room with preferably 23C more or less. Even better say leave it for 24 hours. Then torque to final spec.
Again leave for 24 hours, and recheck the torque. If they dont move, you are set.

RCinXS

Hi Colin.

OK, so final torque should be 65.7 ft.lbs?

Dave928S

There was an extensive discussion on this subject (within the last year?) which discussed whether new bolts/studs should be used and there was also an in depth analysis of torque values and degree rotation versus torque settings. The manual and specs changed over time and give conflicting data. Greg Brown and others had lots of posts ... I'll see if I can find it.

Edit : here it is ... https://rennlist.com/forums/928-foru...ead-studs.html

RCinXS

Hmm.


Thanks for the link. No real definitive answer there, but a lot of good thoughts.

IMHO, Torque by angle should only be for the studs themselves.

At least that is how other Euro engines are done.

Changing the studs could cause big problems. Did this on a 944 and it was insanely difficult. Took a week of heating with a torch. 928s have twice as many studs, so it could take two weeks.

My studs still show golden, which is a good sign of their condition, so I'm not going to change them.

Will change out 5 suspect nuts. All others look like new, with no sign of distortion.

I'll be doing a full posting on the entire Spring Project, which was quite extensive, including an EMS upgrade, in the very near future.

BigAl1

RC,
Sorry for the slight hijack, but are your headnuts original yellow plated? All my engine hardware is grey, so wondering what they should be?

TIA

RCinXS

BigAl1,

I've had this car for a quarter century. I've done the entire suspension , tranny, diff and now the engine.

From what I can tell, as far as the engine, trans, diff and suspension, all the original steel nuts, bolts, washers and studs were originaly yellow / gold, with the exception of ones that were zinc plated. The Pet would show a "Z" after the part number for those.

Once any of the above is apart, you can see the original color of the hardware that was protected from the elements by the oil, undercoat or whatever.

BigAl1

Thanks RC. Engine teardown starts tonight, and I was wondering if I should plan to get my hardware plated or not. Will do so now.