Easy Steps to turbo charging your 5M-GE Supra
by Jake Reed
First I would like to thank Reg Riemer for the idea and inspiration, Steve Lee for the blueprint, Dean Marcum for the tech and part support. I was lucky enough to happen across Steve Lee’s webpage on this conversion and other than a few minor changes I followed his blueprint for this conversion to the letter. The car is in a constant state of change and upgrade that will eventually include a highly modified 6M. The first part of this modification is going to start with the intercooler, the reason being is that it can be done without taking the car apart over even jacking it up. I drove the car around for almost a month with the intercooler in place before I took the car apart.
I know people have used different intercoolers with success. I went with a factory MKIII intercooler just because it came with everything else as a package deal. I built the brackets you see in the pictures to mount the intercooler using existing holes.
After taking the plastic cover off the bottom of the car I noticed to black plugs in the lower core support and pulled them out. To my surprise I found that they were factory threaded holes for the same size bolts that were holding the plastic cover in place. There was also a open hole in the hood latch support that happen to line up nicely for the upper mount. I did not like how low the intercooler hung due to the lower pipe hitting the core support. I cut the tube and fabbed a new one allowing the intercooler to move up higher behind the grill. Looking at the front of the car it is nearly impossible to tell it even there. Now the intercooler can bolt in and out without even jacking up the car.
Fuel is probably the easiest part of the whole upgrade! Again Steve Lee thanks for figuring this part out! Just use a Vortech FMU that is meant for a Mustang 5.0 supercharger kit. Plumb it into the fuel return line on your Supra and you’re in. I mounted the FMU just to the right of the power brakes. I plugged into the fuel return line were it connects up to the “U” bend at the mechanical fuel pump block off plate located just above the left side engine mount. Then for vacuum go to any vacuum line coming out of the intake and your in!
As for the turbocharger I planned many upgrades in the future especially with the new engine. But I wanted to start at the safest levels and build up so the whole system would come along as a whole. It’s a little anal I know but I have built enough high performance cars to know to jump right to the max can lead to very costly mistakes. A little patience seems to go along way in the end. I took a stock CT-26 and sent it out for a rebuild with no upgrades. I took the manifold and had it extrude honed and port matched. One the exhaust manifold you must make a small notch to clear the upper power steering pump bracket between 1 and 2 cylinders. The best way to perform this is to take a dremel and the 5M gasket you just pulled off your car and place it over the 7M exhaust manifold. You will see the amount you have to clearance. Once this is done it will bolt right on.
Now with the manifold bolted on the turbo will bolt up. For the oil feeds to the turbo look under the oil section. The water part of the turbo will take a little of imagination. You can plumb water in from a couple of locations. I did it from the water neck by pulling the plug and running a line over the engine to the turbo. For the return line I ran a hose from the turbo to the back of the engine. There are two rubber hoses feeding the heater core right behind the head. They are connected by a tube and two clamps. Just pull the two clamps and tube out and plumb the second water line in here. A quick run to the hardware store will get you a couple of barb fittings, T-block and clamps or reuse the ones you just took off the car. Depending on how you hook up the oil lines you will probably want to bolt them to the bottom of the turbo before you bolt it on. For me this was the way to go. On 84 and 85 cars there is a charcoal canister that is right in the way of the elbow casting coming off the back of the turbo. If you are in an emissions state that will have to be there. You can either try to relocate it or another option is to but a downpipe flange and get rid of the elbow casting. I bought mine from Dean at TRP Online at (www.trponline.com) this allowed me to bolt the canister in the stock location. This will however create another condition. You know have to relocate the O2 Sensor. I planned on adding a Ford heated O2 sensor back by the cat so it was not a question for me. How you tackle this part is up to you.
For oil you have to worry about two things. Oil pressure and oil return. I got oil pressure by teeing off below the oil pressure sender.
The reason a put the oil pressure sender at a 90 degree position was to help make as much room as possible for the fittings you will see later that are coming out of the oil filter adapter. The oil pressure line then gets run up to the bottom of the turbo into a plate that I made and threaded for AN lines.
For the return line I used the big oil line down to the bolt in the side of the pan. I pulled the plug then went down and got a AN fitting that I turned down and rethreaded on a lathe to screw into the pan.
That took care of the turbo oil duties. Because the turbo down tube goes right by the oil filter it is necessary to remote mount the oil filter or plan on dropping the intercooler tubes every time you want to change your filter. Also it is not a bad idea to add a oil cooler. For the relocation duties I chose the Ford Motorsports 90 degree adapter and some 90 degree swivel fittings.
I put the oil filter out to a location that allowed for smooth running of the lines.
I mounted right in front of the cross member and right behind the stabilizer bar on the passenger side. The cooler got mounted right above the intercooler then it was just a matter of having hoses made and the oil system was setup and finished. Just a side note, when you first do the turbo setup use the rubber turbo downtube out of the turbo to the intercooler. It’s a perfect fit on a MKII and goes around the engine mount and ends mounting out right where you want to go.
For the gauges I went with Autometer air/fuel gauge and boost gauge. I mounted them on the pillar using an Autometer universal gauge pod and some trim screws. It fit pretty good and I planned on going back and building a mount for this location in the future when the car gets some upholstery work done. That’s about it. Remember this is just the way I chose to go and does not mean it has to happen this way.
Article written by Jake Reed (j.reed@sheetmetaleng.com)