Porsche Enthusiasts Club Forum

My plan is that over the winter I shall pull the engine from my GTS and cure the embarassing smoke plume that I get on the over run and find the source of why it runs slightly oily on one side of the engine, the two could possibly be related. I also intend to clean up the engine bay and do the usual top end spruce up on the cam covers and intake.
Now I know there are obvious parts that I will need, rings, main bearings, gaskets, cam belt etc. and I intend to replace any hoses that are usually inaccessible while I'm there. My question is are there any non obvious parts that I should make a specific point of replacing whilst I'm doing it, I figure it's best to do it once properly than have to go back in there sooner than need be.
Final part is, is there one paricular source that I would be best to use or is it a question of hunting round on the net for individual prices?

Hi

Not sure if this will help or put you off...

The GTS early engines had a huge problem with oil useage and MOST GTS engines were changed under warranty...

As far as I understand it, the problem was with the pistons or rather the lower skirt of the piston not being drilled to release excess oil pressure...

What that means to you is that IF your engine was never changed under warranty you will need a set of the later drilled pistons and maybe a lot of other bits,,,and from memory a set of 8 rings alone were over £1000...so pistons would be astronomic

I just checked Pet 7 and can find no pistons at all available from 93 to 95

You really need to speak to Paul Anderson about this as he knows ALL the technical details that you need to know, it MAY be possible for him to remachine and drill your piston skirts as an example.....

One thing that is definite is a bottom end rebuild on a GTS is going to cost you thousands,,,,without question...

Sorry to be the bearer of bad tidings but contact Paul as he may have another engine as a cheaper option....

All the best Brett

Pistons are on my version of PET, still available

Hi

Thats interesting as NLA on my version (Pet 7.1) ...what price are they out of interest ?

All the best Brett

I take it I downloaded the same version of PET from the same site as Brett?

Hi

If you start Pet is has the "Revision" (version) number at the bottom..mine is Revision 7.1 ...

All the best Brett

Mine too.

Brett, I don't actually need to rebuild the engine, it's not as if it's knocking on deaths door, also I could tolerate the oil consumption, the two main reasons for doing this are it's all a bit grubby (not filthy) and really needs a freshen up (clean & repaint of intake/covers etc.) and to cure that annoying puff of smoke I get coming off a trailing throttle. I appreciate if I cure the smoke it's more than likely I'll reduce the oil consumption at the same time. Are the actual pistons different or simply drilled, I'd ask Paul Anderson if I could contact him but the few tiems I've tried previously I think it would be easier to get an audience with the Pope!

The good news is the price of piston rings must have come down as my OPC quoted a mere £921.00 including VAT, bargain, a top and bottom gasket set just shy of £700.00, might be cheaper to put a Corvette engine in there instead.

Hi

Ok... mines an S2 and has always used a LOT of oil..I guarantee its at least double yours lol....

My nitrous system has made it worse but I live with it....

Two reasons for that...firstly nitrous LIKES a "loose" engine as it gives excess pressures somewhere to go if you see what I mean...lol

Secondly and more importantly to you, the reason I don`t sort it out ..things like major puffs of smoke on the overrun is ,,,,,cost and time,,,,I KNOW whats involved in stopping those puffs of smoke (including new or redrilled pistons)

So I chose the "cheap way" ...and now you will laugh...lol

The breather system on 928s is set to blow excess oil pressure into the exhaust manifold then out the back....your "annoying puff of smoke I get coming off a trailing throttle"

Soooo...a SHAMPOO BOTTLE is my cure....having been a Race mechanic for years, we always used to say the simplest ways are usually best...


What you do is tuck a large shampoo bottle down the front right of the rad...and divert your top breather into the bottle via a length of silicone pipe....

SO... the engine gets excess pressure and it mostly goes into the bottle...not all but most, and believe it or not its rare to even half fill the shampoo bottle over months as its mostly smoke and not actual oil....

If you really want to cure it totally..you may need a set of pistons , or your pistons drilling, plus a full engine rebuild and possibly a rebore which is NOT easy or cheap because the block is aluminum with nikasil plated(alusil) bores! Although the plating is around 10thou thick on these blocks once the bore is worn, there really is no easy fix.

So although you may not need a rebore, you will not find out until the engine is stripped...etc etc...

I am not saying do not do a top end clean up...thats a good idea on any engine...but the bottom end is a totally different kettle of fish on our engines....

Hope this helps...

All the best Brett

Latest PET is revision 7.2 update 258

What size pots were you after?

Brett, thanks for that, I previously ordered a Shark Vent which I think pretty much does the same thing as your suggesting but in a neater and more expensive way. I cancelled it as a) after 3 months it hadn't arrived and bugger me if their stock didn't come in just as I cancelled it! & b) somebody else suggested that the only way I'd cure this was to drill the pistons. With b) in mind I cancelled the Shark Vent ( http://www.928gt.com/default5.htm - Xtreme version) to put the money towards the rebuild.
If you think that by re-routing the crankcase breather I'll go back and order the vent kit, I know it's dearer than a shampoo bottle but it's way cheaper than a rebuild, then all I'd need to do is the top end refresh?

Hi

I "thought" about the various "vent" kits with mine but after reading various reviews by people who had fitted them came to the conclusion that as they all said...they DIDNT cure the problem..only helped a bit.....therefore my shampoo bottle...lol...if you want the posh version of my shampoo bottle you can buy ally breather cans...
So yes in your case...a top end rebuild or refresh.... and no bottom end rebuild unless you want to spend some SERIOUS money (thousands)...

All the best Brett

You can drill your old pistons. Get in touch with Adrian Clark.

John, thanks for that although obviously that will mean an engine out and bottom end rebuild that Brett was saying will cost the GDP of a third world country.

Hi

Where did you get 7.2 as mine just updated as usual every few uses and mine is "7.1 258/28" ??

All the best Brett