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911 Turbo Rod change

I am always amazed when people call to talk about our engine builds and how shocked they are that the case halves do not need to be split in order to change rod bearings. I have been building motors for about 17 years now and have always done this. Often a customer will have a low mileage 930/911/993TT/996TT/997TT motor and want to add HP but typically doesn’t want to spend the extra 1200 to split the lower end. This in turn usually detours the individual from modifying anything. I will admit that the first time I tried this I too thought no way can this be done. The procedure is pretty easy. Once you get to the point that the piston and cylinders are off you can access the rod nut and bolt. You will want to have a couple of things handy, first and most important is the telescoping magnet and your extension with the socket on it for the rod nut and a small hammer. I mean very small. Take the rod and rotate it so you can reach both nuts. Loosen and remove the lower nut. Next loosen the top nut. Do not remove it yet. Now take your socket and extension and gently tap the end of the extension on the nut. The rod halves should loosen up. Next take the magnet and hold the back side of the rod. The rod end cap is the part that you need to keep from dropping in the case. Pull the nut off and pull the rod out, now rotate the end that you are hanging on to with the magnet and pull it around the crank and pull it out of the spigot hole. Rod is removed.  

Install is a little more tricky. Simply not enough room and usually unless your are a mouse your hands are not small enough. Mate your rods and stronger rod bolts together. Both ends of the rods will be stamped. Keep the rod orientation the same as you assemble the rod in the motor. The numbers should match each half and face each way. Line the threads with molly grease or oil as the manufacture suggest. Load the bearing in to the cap and place a drop of oil on the bearing and a prelube like redline on the face of the bearing. Place the end of the rod on the crank and spin it around until the bolts are facing you. Gently place your magnet on the edge of the upper portion of the rod and hold it in place. This should keep it held where you need it to place the other end of the rod over the bolts. Place the rod over the bolts holding pressure on the back side of the rod pulling the end towards the front section. Start your nuts on the top bolt, then the bottom and gently tighten them one turn at a time until eventually seated on the crank. Tighten to spec with TQ wrench or TQ based on prestretch prior to installing.

 Once on, use rubber band to keep the rod center and dragging on the spigot.  I know, the world’s cheapest Porsche tool! No there is not a P number for that one =) 
It may take a few times to get this right but it is possible and I have built hundreds of motors this way.

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Rods ready for bearings. Normally I will match numbers and halves together with a paint pen as not to mix up the ends when putting them in the case.

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Redline pre-lube and oil on bearing.

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Placing rod end on the crank.

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Rotating rod end on crank to face bolts outward.

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Holding rod end in place with magnet

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Placing Rod half in place and starting top nut.

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Fancy Porsche made rubber bands holding rod center and in place.

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