Rob Edwards

Also has the GTS-specific notches in the sides of the girdle for rod nut clearance:

atb

Well, I stand corrected. On closer inspection with a light, I do indeed have the ports. For some reason I was envisioning two ports lower on the webbing, closer to sides of the crank journal. Instead there are three ports, positioned much higher on the webbing (what can I say, I've never looked inside a GTS motor before). Looks like this is indeed a GTS block that had S4 internals installed.

Bigfoot928

that is a rare engine... one where the dealer got the block warrantied, and switched over all the internals......somebody made some serious coin on that service....the question is... did they replace the rings... I would do a leak down test to be sure.... and a compression test too..

atb

Dude, I've been driving the car for 15 years (see below) .....

Sander_Baas

Hi,

Quickly jump in to this if I may,
I have a 87S4 where the previous owner changed the engine from. What came in place is a GT engine. At least as far as I know, on the flat surface next to the oil filler neck stands M28/47. But no serial number (as I understood usually stands under it) I did some searching and found out as also mentioned here that, then I could be a Porsche rebuild engine?

Then I noticed after reading this thread that if.. you have the bolts vs. studs, round breather holes in the main webs & notches in the sides of the girdle for rod nut clearance? That it’s a GTS engine “core”? so in my case a GTS block with GT internals?

Added a few pictures I made when replacing my oil pan gasket, circled in red what I think are the specific characteristics that are mentioned here?

Thanks in advance
Sander

atb

Welcome to the club.

Any others out there?

Sander_Baas

Nobody? :-)

But these engines then must be ≥93?

Hilton

Bleh, my 87 must have received its warranty block too early. It has nuts, not bolts, and is missing the scallops for the rod nuts.

Here's its engine number




Annoyingly, its original block was the second-last manual squirter block the factory made.. so because some previous Marquis buggered its engine, I didn't get the squirter block.

Richard S

What were the last 4 digits of the VIN on the car? Just curious, as I don't think I've ever seen a definitive VIN of the last squirter block car.

Rich

Rob Edwards

And the serial number of the engine block, from the stamp pad?

GregBBRD

The "excitement" of the squirter blocks always makes me smile....

Porsche didn't continue making squirter blocks past that little run, because they didn't work....they robbed too much oil from the system.

Everyone knows this, right?

Hilton

The VIN is a RoW car and thus won't relate at all to the US VIN series.

I also made a mistake - my S4 from 87 was third-from last manual car with a squirter block. The last manual squirter block engine number is stated in factory documentation - 81H00677. The docs don't provide the upper bound engine number for auto's - but IIRC the youngest auto box confirmed with squirters was Greg Nettles'. He posted pics years ago of them.

Rob Edwards

Actually I've never heard that. Were there problems with clacking lifters or (worse) cam issues in early '87's?

ptuomov

My understanding is that the squirters resulted in too much oil on the bore walls, which is an ongoing problem with most of these engines especially at high rpms. The results are ring flutter, detonation, excessive blowby and crankcase pressure, oil drainage problems, etc.

If my understanding is correct, for a low rpm forced induction motor with a good ring solution (like in George Suennen's motor) and effective windage control, squirters may be a net positive. For a higher rpm motor without as good of a ring solution and ineffective windage control, they are probably a net negative.