AO

The only options that I know of is Cometic, Victor Reinz, and OE (which may be made by Reinz). There have been many discussions in regards to the Cometic (use search) - some good, some bad. I'm leaning toward the OE set just becasue I know they work this long - would hate to put something that may or may not work. I'm sure I'll solicit other's opinoins before too long - but those are like elbows and a$$holes.... everyone has one.

drnick

i agree and i think it may be a while longer before the numbers of blown sharks with headgasket experiences comes up enough so the discussion becomes anything more than an experience from one or two. ive heard the big problem with the 928 and headgaskets is if there is any aluminium corrosion on the block side.

Peter F

Reinz head gasket was used by Porsche according to Reinz own advertisements.(Not sure when this was used though)


/Peter

Vilhuer

In 1977 I believe.

Vilhuer

I Italy there is company which can do metal gaskets in few different configurations which supposedly work better than Cometics.

123quattro

You can get MLS gaskets made in the US as well. They are superior to all other gaskets. However, to run a set of them, the block and heads would both have to be machined. They require mirror smooth surfacing on both sides to seal correctly.

Peter F

If only in 1977 that was a very short time of the 928 lifecycle and would mean that Andrews head gasket is not original then?
Or did you mean from 1977 with an unknown end Year?

/Peter

AO

Can someone tell me the best way to measure the bore? I want to make sure I didn't balloon or otherwise change the cylinder.

I used my digital micrometer and it measured 99.6mm IIRC - same as the other cylinders. Specs say it's supposed to be 100mm. Is there a difference between a hot and cold engine?

BC

Watch your words here John. This Subject is extremely controversial, and could get you banned. You must believe and testify to the fact that the 30 year old Fiber gaskets are perfectly fine for an open deck block and boost to get the secret decoder ring.

But other than that, you are exactly correct.

Vilhuer

All years basically from 1977 up to today. I think that ad appeared when 928 was introduced or very close to same timeframe. 928 was something they and many other companies could be proud of to be involved with and thus they used it in ads. In later years there were usually newer examples of cutting edge design which could be used. So window for 928 to be in spotlight was few years in most companies.

Tech spec book has exact instructions how deep and what direction to measure. MEasurement is done in room temperature obviously. To do it correctly you need special measuring devices. Check page 7 on this catalog for few examples:
http://www.ikh.fi/hallinta/pdf_tiedo...ategoria_id=13
Product number SC013 is set of spring loaded telescopic tools which are inserted into cylinder bore and locked to position while there. Then tool is removed from cylinder and its diameter is measured with standard micrometer which is large enough. Result isn't very accurate and probably will not be good enough to say even what tolerance group bore is not to mention if it is in small or large end of the said group.

For better measurment you need something like SC080, standard dial indicator like SC030 and micrometer like SC031 shown in page 6. Measurement is taken by inserting SC080 into cylinder bore same way as cheap spring version while dial indicator is installed at its upper end. Dial is read and result noted down. Number in itself does not tell anything directly. To find out actual measurement SC080 measuring head is put between micrometer, micrometer is turned until dial on other end of SC080 shows exact same number as it did inside cylinder and this postions is read from micrometer and its actual diameter for measured cylinder. This kind of setup is cheapest way I managed to find which will get to precise enough level to be useful in measuring diameter of 928 blocks. SC080 alone was close to $500 in here so there really isn't cheap way to check bore.

There are much more expensive digital bore gages available but those are really too expensive for simple hobby use. Check out for example http://www.mitutoyo.com.

AO

I can't... but I guess that's part of my question.

If the cold value is less than 100mm how am I to know what the correct value is? Of course, I am using a HF digital micometer, so who knows how accurate that thing is.

AO

Ahhhh found it.
Now I need to see if I can rent/buy the right tool.

69gaugeman

If you could wait two weeks I can get you the correct tool.

AO

Thanks Rod. Let me see if I can rent one (for free) from one of the local Autoparts stores.

BTW, we missed you. Will you join for the install party?

the flyin' scotsman

From our friends at Snap On:

http://buy1.snapon.com/catalog/item....da&dir=catalog