SHO into a 912
 

So, I rescued a sad '66 912 that was headed to the scrapyard many years ago, had big plans for it but not a lot of money or skills. It ran and drove, but had a VW engine in it and rust in the usual places. I took it completely apart and started cleaning, sandblasting, and rebuilding what I could, but got sidetracked and the project got put on the back burner. one thing led to another and 20 years went by.

Fast forward to now - moved out to the country, built a shop, realized I'm not getting any younger and better get to work on the Porsche. Admitted to myself I'm not anal enough to do a real "restoration", it's just a 912, not a 911S, and I'm a hot rodder anyway, so might as well build it like I want. Didn't want to go with another VW engine, not going to pay ridiculous prices for a 912 engine, didn't want to go with an LS V8 like everyone else seems to (I've got 3 of those already in other vehicles), decided to swap in a 3.0L SHO V6. Yes, they came with god-awful Ford Tauruses wrapped around them, but the SHO V6 was designed by Yamaha and are pretty sweet little motors. Only 220hp stock, but plenty for a little lightweight bare bones 912.

I've searched far and wide, and I haven't found anyone else that's done this exact swap, although I did find people that have put SHO's in just about everything else - a 914, an Austin-Healy, Ranger pickup, etc. Kennedy Engineering actually makes an adapter kit (plate, flywheel, clutch) to mate the SHO block with the Porsche 901 transaxle, but I had actually fabricated my own adapter plate out of 6061 T6 aluminum before I discovered Kennedy.

The project is still underway, going slowly as I find time to work on it, but at least it's up on the lift in my shop rather than shoved back in a corner gathering (more) dust. Here's a few photos of the "progess" so far:

http://forums.pelicanparts.com/uploa...1515856754.jpg
http://forums.pelicanparts.com/uploa...1515856784.jpg
http://forums.pelicanparts.com/uploa...1515856826.jpg

Great idea! I never click on this thread but had to check this out, I remember riding in a SHO back in the day, 1992 ish.

FYI Rick Titus made a few SHO into Ford "Festiva" I think & called them Shogun's, Jay Leno bought one.

http://forums.pelicanparts.com/uploa...1516140826.jpghttp://forums.pelicanparts.com/uploa...1516140903.jpg

It's tight. but engine lid clears intake.....barely. Oil pan is about 1 inch lower than transaxle.

I have to commend you for taking on a different approach and doing a very interesting swap! I'm quite interested to see how this swap goes. Please do keep us updated!

Updates? Those are great engines.

I thought the block on those was ceramic??

Had to fabricate another rear engine mount crossmember, the first one I made to clear the A/C compressor ended up too far away from the factory 912 engine mount brackets - so I decided to get rid of the A/C compressor and it's heavy cast iron bracket (saved 35 lbs) and simplify things.

I used an aftermarket tubular crossmember that's made for swapping transmissions into hot rods - it's nice and strong, and the bend in it clears the SHO oil pan perfectly. I fabricated plates to bolt to the sides of the engine block and the brackets between them and the crossmember, and used round tubing to attach the ends of the crossmember to the factory Porsche engine mounts.

http://forums.pelicanparts.com/uploa...1524962263.jpg

http://forums.pelicanparts.com/uploa...1524962694.jpg



I ordered a custom flywheel from Kennedy, it will bolt to the SHO crank, mate with the original Porsche starter, and allow the use of a 228mm (9") clutch disc and pressure plate. I also picked up a set of 30mm diameter rear torsion bars, which will be needed to support the added weight of the iron block V6.

I fabricated an adapter plate to bolt the SHO block to the bellhousing of the 901 transaxle out of 5/8" thick 6061 T6 aluminum. It wasn't complicated but having to clearance a "pocket" in it to clear the bolt-on breather at the rear of the SHO block was a little tricky, and I ended having to use countersunk bolts for two of the plate-to-transaxle mounting holes to clear the breather and the SHO oil pan.

http://forums.pelicanparts.com/uploa...1524962584.jpg


Once I had the engine mount done, I bolted the engine in to the Porsche and raised the entire vehicle on my 2 post hydraulic lift to find the center of gravity - it ends up right at where the rear torsion bars are located, which is pretty far back. I had to put some weight in the trunk (battery and spare tire) to keep the car from teetering on the lift arms.

Fascinating link, and your project is remarkable.

Love seeing that old Bronco in the background. :)

Thanks- the Bronco is another long term project, drug it out of a field back in 2001 and have been working on it off and on since then. Stripped it down, pulled the body off the frame, had it sandblasted and powdercoated, built a 351W, dropped in a ZF 5 speed, Dana 44 front and 60 rear (full float) axles, converted them both to disk brakes, etc. It's coming along.

http://forums.pelicanparts.com/uploa...1525453157.jpg


http://forums.pelicanparts.com/uploa...1525453224.jpg


http://forums.pelicanparts.com/uploa...1525453293.jpg

Looks strictly off road from that stance, and a lot of fun.

The flywheel arrived from KEP, they do nice work. Clutch face is machined for a 228mm (9") clutch disc and pressure plate.

http://forums.pelicanparts.com/uploa...1525706759.jpg


The 8 holes for the crank bolts are drilled perfectly, the center bore is a nice tight fit over the lip at the rear of the SHO crank, and the ring gear for the starter just BARELY squeezes into the 901 transaxle bellhousing. They include the bolts and a roller pilot bearing.

http://forums.pelicanparts.com/uploa...1525706860.jpg

http://forums.pelicanparts.com/uploa...1525708279.jpg

Man, those are some big honking cylinder heads, aren't they?

http://forums.pelicanparts.com/uploa...1525708305.jpg

I like this swap!

Very cool. Subscribed!

Awesome project! Love the Yammahammer!

Sweet swap indeed, following with interest


Sent from my iPad using Tapatalk Pro

whats happening here??? no updates

Haven't made a ton of progress lately, so many other things going on don't have as much time as I would like to spend in the shop. I did spend some time (and some money :( ) trying different options to fit the huge SHO intake manifold and throttle body into the 912 engine compartment.

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.


http://forums.pelicanparts.com/uploa...1549840340.jpg
http://forums.pelicanparts.com/uploa...1549840384.jpg
http://forums.pelicanparts.com/uploa...1549840416.jpg


I'm still in the planning stages, so the tubing is held together and in position temporarily with silicone couplings, once I know where everything will fit it will be tig-welded. To enable the use of a single throttle body, I used a 2-into-1 collector fabricated from stainless steel that's normally used in custom motorcycle exhaust systems.

I'm also working on mounting a small, lightweight, 90 amp single-wire alternator to replace the heavy stock Ford alternator. The original alternator mount was also the air conditioner compressor mounting bracket, and was a huge lump of cast iron. Doing away with that, the A/C compressor, the stock alternator, and power steering pump and bracket dropped a lot of weight off the engine and cleaned up the looks as well.

Keep going!
Very interesting.

If it's any motivation to help keep you going there are a lot of us interested in your plight simply because it's something we think of but would never have the guts or patience to attempt.
I for one am glad that you've posted here and will continue to follow your journey.
Tony

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. :)

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.

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

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 ?






Sent from my iPad using Tapatalk Pro

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.

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.

Hi,
Any updates?

Great Job so Far!