I have an '88 S engine that has the forged rods. Well I believe it does, the part number ends in RARST. But then so did the '87 and '88 turbo engines I have had apart.

One other difference is the bore for the oil pressure relief valve. The '87 and later is a different diameter.

I personally prefer the earlier method for tensioning the cam belt. The spring tensioner is not all that helpful. But that is just me. you can easily convert the later engines to the stud and eccentric roller.

 

I know for a fact, I have the 1 piece pressure relief valve. Hmm, now I really want to get my rods back from the machine shop.

~Eric

 

Okey, so an -86 engine bolt on without problems on a -87 car?
Are the engine management system, DME KLR, exactly the same?
Just some minor mecanically changes then?

Thanks
/Peter

 

The 87+ DME takes 28-pin performance chips, the pre-87 DME uses a 24-pin socket so. Most chip makers can adapt their chips for either DME.

 

The 91 cabrio has NOT forged rods. at least the one I saw.
The 88 NON S 951 I saw has forged rods.
some 89 951 did NOT had forged rods (at least the one I saw)
Porsche started with forged. The ystarted changed in cast rods after the 87 abt they still put forged rods since they had many remaining.
in 89 they used only cats since they didn't had any forged more and there was no reason for forged.

NOT all 951 has the exteranl oil cooler.
In ROW yes but in the USA in 86 it was an extra option.
later it was standard for both version ROE and USA

Same with the gear box oil cooler.
Not of all them had it and not all LSD car had an oil cooler

Konstantin

 

The 87 engine had an updated water pump that has a plate on it. The cam belt teeth come perilously close at the water pump. This plate keeps the cam belt teeth from hitting when the belt stretches.

There was a different oil pan between years.

The early water pumps and oil pans have been superceeded and are no longer available.

.........and I say no forged rods in 87 (stock). But I agree with Konstantin, (just like the water pump/oil pan) when an item is upgraded and there are no major durability/safety issues, Porsche uses up all remaining parts before the upgraded part is fully integrated. Good business sence.

 

The chips in the DME have a different pin count but the external connection is the same and they are interchangeable.
The oil level indicator will not work – 86 pan does not have the sender, other than that you can bolt it in and start her up.

Chris White

 

One thing I have learned that is very surprising, you can't always believe the Porsche manuals.

Lou