SHO into a 912

[jadewombat]

Just as the Mercedes 500e was the original 4-door Porsche, it'd be cool to see the Yamaha name on this motor when you open the decklid.

[earlybroncoguy]

Still working on the project, since I bought the engine years ago and have no idea how many miles are on it or it's past history, I figured I better go through it and see what needs to be replaced before I mount it on a run stand to fire it up and get all the bugs worked out before I try to install it in the 912.

SHO V6's have been out of production for decades, and weren't exactly commonplace when they WERE in production - as a result, parts can be hard, or impossible to find. I think I scored the last set of standard size connecting rod bearings on a certain website that apparently I can't say here, but rhymes with "MockLotto" . Main bearings are no longer available. Head gaskets are hard to get, and expensive ($90 each) when you can find them.

Since the engine had been sitting so long in storage, mice had decided to try and build nests inside the water pump inlet pipe, the water passages in the cylinder heads, and I swear inside the engine block. I had covered the intake and exhaust ports way back when, but didn't consider the water ports.

I removed the oil pan and cleaned it, replaced the rod bearings, removed the cylinder heads, and blew out the coolant passages in the heads and block to get the mouse nest materials and droppings out. The rod bearings didn't look bad, but the rod side shells had some shiny spots where they wore down to the copper backing. They measured OK, but I went ahead and replaced them with the new ones I had. Crank journals were smooth and shiny, no gouges or scratches.

Cleaning everything now in prep for painting and reassembly.

[SHOsource]

A friend sent me the link to this thread, and it is my first post to the forum.

A little background on me (us). We inherited a pretty clean 912 that has been repainted to a different color and also sports a VW engine. The car does not get the love and use it deserves, but it does live covered in out barn and we keep it maintained. We also own a super clean, low mileage 2001 C4 that I went through to install the IMS bearing upgrade and all the other parts to keep that car on the road. It is my wife's daily driver. I just wanted to establish we do own and drive two Porsches.

The main reason I am posting is because I am also heavily involved in the SHO community. I own the website that matches my username. I have lost count of how many SHOs I owned, and I have been inside and outside the SHO engine, transmission, body, suspension, etc enough to recognize where bolts and brackets go by sight. I have also helped a lot of people with transplant issues (914, dune buggys, sand rails, Cobra kit cars, XR4Ti, Rangers, etc). If the OP ever needs any help, with this transplant, I am willing. I have a lot of parts available new and used that are not normally listed. In this case, it might make sense to use two left or two right exhaust manifolds for symmetry. It might even make sense to use manifolds from an automatic version to gain some clearance. Additionally, we are working with a guy that just made a plenum style intake which could simplify the installation. I know the SHO intake snakes are one of the most beautiful parts of the engine, but a low profile plenum that allows you to gain a lot of clearance and also use a clamped in throttle body and MAF could be worth the sacrifice.

Awesome build. I am subscribed.

Mike

[Andy Somogyi]

What if you welded a pair of flanges to the sides of the intake manifolds and went with a dual throttle body approach, with the throttles opening to the side ?

Originally Posted by earlybroncoguy

The bolt pattern and intake ports on the intake manifold are symmetrical, which allows the intake to be installed either "forwards" or "backwards" on the engine (throttle body towards front or rear in a longitudinal installation), but unfortunately neither option will work well for my 912 - since the throttle body is at the extreme end of the intake, it would either be protruding through the firewall, into the back seat area (if installed frontwards), or several inches outside and above the engine lid (if installed backwards).



I considered using a 911 Turbo engine lid and whale tail to allow room for the intake and throttle body mounted facing the rear of the car, and even purchased an aftermarket fiberglass engine lid and whale tail, but the fit of the throttle body was still too tight, and I really want to keep the body of the 912 looking as stock as possible.



I ended up deciding to block off the original throttle body opening in the intake manifold, and instead use the opposite ends of the plenums, which are normally connected by a crossover tube. The openings in the ends of the plenums are 2" in diameter, which if combined, gives more area than the original stock 65mm opening - and, with the use of mandrel bent aluminum tubing to mount the throttle body in a different location within the engine compartment, allow the intake to fit under the stock 912 engine lid. Maybe not the most ideal situation, but doable.













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Sent from my iPad using Tapatalk Pro

[K24madness]

I always loved the SHO engine! Test drove one of them in it’s day but could not swing the $$$. Oddly enough I landed in a VW Quantum that led to Audi and then to Porsche. Similar roots!

I think this engine will be a great match for your 912. While it does not put out big numbers it does have a GREAT revvy personality that’s well suited for the 911 platform. Kudos for taking on the task!

I understand packaging problems but moving throttle bodies changes that finely tune intake volume. Keep that in mind as you progress. Not sure how all that extra volume will play out. Maybe good or bad.

[K24madness]

I always loved the SHO engine! Test drove one of them in it’s day but could not swing the $$$. Oddly enough I landed in a VW Quantum that led to Audi and then to Porsche. Similar roots!

I think this engine will be a great match for your 912. While it does not put out big numbers it does have a GREAT revvy personality that’s well suited for the 911 platform. Kudos for taking on the task!

I understand packaging problems but moving throttle bodies changes that finely tune intake volume. Keep that in mind as you progress. Not sure how all that extra volume will play out. Maybe good or bad.

[dtakenname]

Hi,
Any updates?

[rahtidone]

Great Job so Far!