3.6 Liter Engine Swap
1989 – 1994 3.6 liter C-2, C-4 engines are plentiful on the used market. Be careful of 1989-1992 engines, they were updated as a warranty. Cylinders were changed and heads were machined. All this because of head surface sealing problems (head gasket). If updated properly the engines are OK. If not, look out!!! Your looking at a large expense to do the update. You can tell if it has been done by looking at the cylinder head surface. This can be done while the engine is assembled. You can see the fresh radial machine marks on the bottom of the last fin. To make sure you have an acceptable engine, check for complete wire harness, motronic relay and E.C.U. These are a must and contribute to the ease and relative low cost of this swap.
Installation varies according to the year of the chassis and transmission combination. 3.6 liter 993 engines are also a great choice. This information is pertinent to the 1995 model year only and not 1996 and later OBD II systems.
Preparing the Engine:
The factory exhaust systems are not compatible for the early chassis, nor are they any good for performance. B&B Triflo has made for us special large tube headers for 3.6 in to early chassis for approximately $1,350.00. Muffler choice is then open to any B&B version from straight pipes to 93 DN Lime Rock Silencers. All make good power and are available thru Bodymotion. We even have mufflers with single and twin outlets. Also available for street driven cars are high flow catalytic converters, they work great and are easily removed if need be for track events.
Next is the mounting at the rear to the chassis. In order to retain the 3.6 sheet metal, which we recommend because it is neat and keeps the wiring in place. This mounts the engine about 35 mm lower. Good for lowering GC, but you need custom mounts. We sell Billet mounts express for this purpose. It requires removal of the 3.6 rear engine mount and a/c bracket. Your old 2.7-3.2 mount will bolt right on. The only difference is that the 3.6 crank pulley will not fit into the 3.2 or earlier mount. Bodymotion to the rescue!!! We have beautiful Billet pulleys made. While you are at it, you need to remove the two speed fan alternator arrangement. Our Billet fan hub does a great job. The fan conversion is approximately $150.00, crank pulley $240.00 and the mounts are about $100.00. Remount the ignition coils to the rear engine crossmember. The power steering pump, mounts and lines get removed. Use our Billet blockoff kit approximately $125.00. Run the new 3.6 wire harness thru the fire wall to under the driver’s seat. Mount the ECU, relay and altitude compensator (if so equipped). The unused sensors (climate control, anti-lock brakes, etc.) must connect to something or the computer will store unnecessary codes. We have an adapter harness for 1990-94 cars and another for 1995 and up models (cost is approximately $350.00).
Hooking up fuel lines requires some fittings and adapters – made up from a Bosch fuel injection repair kit, basic plumbing – feed and return. All Bosch pumps from 75 up work just fine.
As far as oil lines go, use the oil scavenge line supplied with the B&B header or use part number 930 107 741 11/911 107 743 10. The feed from the tank depends on the donor engine year . 1990 – 1994 engines need to have a 25 mm stainless tube T.I.G. welded into the inlet fitting using the threaded half to screw into the case and the hose end to attach to the stock “S” hose. One note: use some aircraft heat shield over the “S” hose. The headers tend to bake the rubber after shut down and will cause the hose to get brittle. On the 993 version (1995 and up) the engine has an oil filter console and uses an “o” ring fitting for the feed. Cut the case end off and T.I.G. weld a 9″ section of stainless tubing from the factory 993 line. This works great and saves the hassle of finding the correct size. We will make these lines for you if you send us your fittings. Clutch and transmissions are next. We have done 915, 930, G50-50 and recently a six speed. Stay tuned, we will bring this to you in a few weeks.