V2Rocket

Would like to gather some thoughts on 951 connecting rods.
There are a few excellent and not-crazy-expensive aftermarket options out there, but I would like to focus on the OEM forged pieces.

At this point the newest OEM forged set is 28 years old, fitted sometime during the MY89 production run before the changeover to regular cast rods.

If one were going into an engine for an overhaul and had the OEM rods out, what can be done to ensure maximum reliability/continuing life?

I am thinking...
- magnaflux for cracks
- shot-peen the rods to stress-relieve the outer surfaces
- replace the rod bolts with ARP
- have the MichaelMount RodMod done (dual benefit - ensures big end is round again, and gives a more durable bearing)
- re-bush the small-end

Any other treatment/work that can be done to them?
I realize that the cost of the above approaches buying for example a set of Molnar rods but then you would still be using stock Glyco soft bearings.

Paulyy

http://www.forgedpistonparts.com/944...-968-cup-s2-s/

Nothing wrong with the glyco bearings. When i pulled my motor apart. The bearings where still good. 120miles on the block.

If you plan to use the MM bearings, i believe you'd be revving the engine a lot and past the original limiter. If so, then id plan on lighter rods regardless.

Auto_Werks 3.6

Pauly, there are lots and lots and lots of problems with glyco bearings on the 911 side. Newer made in Poland parts have definitely had tolerance problems. I have never heard of any problems with Porsche branded glycos, they seem to go through additional quality control processes.

odonnell

They're just super soft. I know that's the point of bearings relative to the crank and rods, but somehow other cars manage. I discolored mine slightly when plasti-gaging. Very minimal, but just where the crank reacted against it as the rod cap was torqued...from pushing them that last .0001" into the races.

blade7

By the time you've done all that it could be 1/2 the cost of new forged rods, plus you'd get something for the old ones. I'm not sure every engine up to 89 had original forged rods either ?

V2Rocket

Right...but like I said you're still stuck using the stock soft bearings with questionable quality control, despite your "improved" rod.

Paulyy

So many people have used them here with out any problems. The biggest problem is people using synthetic oil which the bearings are not designed for.

blade7

I've been using Millers 10w50 CFS in my car for around 20k without any drop in oil pressure. Did get an oil leak with cheaper 5w40 synthetic when I first had the car though.

Auto_Werks 3.6

Lots of people do lots of things. It's absolutely possible to get a good set of glyco, and I would probably buy a NOS set that was made in Germany. Within the last two years I have rejected a set of 951 glycos for surface defects. They are supposedly fine if you do your own quality control and checks. The place I bought them from eventually admitted they don't use them on their in house builds... OEM Porsche only. The OEM Porsche parts I replaced them with were better fit and finish hands down.

Auto_Werks 3.6

Bearings are fine with synthetic. I do run conventional on the street, but my race car does not.

Auto_Werks 3.6

You did not discolor the "bearing". They have a film on them to keep them from corroding or something. It can be wiped off with aggressive paper towel use. Some people remove it completely before running... I do not... that is of they're the glyco branded new parts that are like a magnesium off white looking color .

Paulyy

I bought porsche glyco ones. but you would think if made in the same factory, it should be the same?

MAGK944

Sadly it's not the case. At a European factory that I arranged parts to be produced for a client they offered 5 levels of quality on the same part and the price varied accordingly. I've also had the same levels of quality offered to me in China. I've seen a factory produce items for Harbor Frieght and the same items for a highly respected tool manufacturer, in the same factory and using the same blanks. There was a 10x difference in the price of the finished products. Buy the Porsche branded ones.

RT930turbo

I'm curious what the difference is in bearings designed for synthetic oil vs conventional oil.

Auto_Werks 3.6

I don't think they are made in the danger factory. ... I've never (personally) seen a Porsche branded bearing that was made anywhere except Germany. Only the OLD NOS glyco brand are made in Germany. They're from poland, and third world countries. Also you can achieve higher quality on the same production line by increasing the scraphone rate.... hold tolerances closer and throw away pays outside the range. This also drives costs and prices up. The other content about selective quality levels seems likely too. Remember, glyco isn't offering different levels to porsche. They're offering one product to porsche, and a different one to us.