Supercharging Toyotas 2TGEU by Tim Frost
Due to the interest and inquiries I have received on exactly how I grafted a 4AGZE supercharger on to the 2TGEU, I have decided to write up a pretty much step by step guide on how to do it. Firstly, you're probably wondering "Why bother, why not just install the whole 4AGZE motor" or "why not just drop in a turbo 3TGTEU"?? Well, they were all considered, but I didn't take this path for a couple of reasons. Firstly, I already had a fully detailed and fully rebuilt 2TGEU sitting in the engine bay of my TA22 Celica, so I wanted to keep it. Secondly, I wanted to do something that was original and not follow the masses of other people using 3TG's or 4AGZE's. The process of installing the blower itself was total trial and error, as I knew no-one that had done this before, and there are no parts that I know of to let you just "bolt it on". The initial installation of the supercharger took a few weeks of playing around in my shed at home, with numerous trips made to the local Toyota wreckers for parts that I thought might help me out, but to re-do one now would be a snap, as it will be hopefully for you. First of all, I started off with a 1GGZE blower off of the 2L six cylinder, but try as I might to make it fit, it was just too long and fouled on the engine mount. I was keen to run this blower as it had a greater displacement that the 4AGZE blower, hence a higher boost figure and more power!!! Luckily, the Jap wreckers that I bought the blower from allowed me to swap it for the smaller 4AGZE unit. This fitted perfectly with about 5mm space between the back of the blower bearing housing and the engine mount on the inlet side. The hardest part of the entire installation was working out how to mount the blower to the block so that I could be easily plumbed up to the intake manifold and make sure that the belt used to drive it was in perfect alignment with the crank pulley and the supercharger pulley. This was eventually accomplished my modifying the standard 2TGEU air conditioner bracket. This was cut in half horizontally so as to discard the bottom most block mounting position, so only the top two mounts are used. Be sure not to cut off the arm that supports the air-con belt tensioner, as this will be utilized later. These mounting points are then bolted to the block using spacers of about 20 - 25mm so as to give you enough clearance once you mount the blower. The blower is then mounted to this bracket by simply using one long bolt, similar to how you would mount an alternator, allowing it to swivel around along the one long bolt. Once mounted, you will be able to move the blower forward/backward along this bolt, allowing you to precisely line up the crank and supercharger pulleys. Once you have made this alignment, washers/spacers will need to be put on the bolt to take up the slack and permanently align the two pulleys. On the aircon mount, there is a belt-tensioner built in that we can use to tension the supercharger belt. This does need a bit of modification so that it can accept the multi-ribbed belt used to drive the supercharger, rather than the V-belt that the original air-con uses. After a lot of looking through the wrecking yard, I found a ballraced idler pulley from the 3SGE motor. This is located on the front of the 3SGE and is used to tension the timing belt. Remove the original pulley and just bolt this up to where the V-pulley came off of the tensioner and your set (may need to space it or whatever to get the correct alignment.) The last thing that you need is to change the front crank pulley to accept a V-belt (alternator and water pump) and a wide multi ribbed belt to drive the blower at the same time. The one that I used was off of a 4AGE (AE86 Corolla I think????), as this slides straight onto the crank shaft of the 2TG, but you will need to use a spacer behind it as the collar that gets pushed through the timing cover and into the block is too short. From memory, I think that it has to be about 22mm long. I cut 22mm off of the back of the original 2TG pulley and slid this on the crank first as a spacer, followed by the new pulley. Now your pretty much set. Just find a belt that is close to the right length from the wreckers, and take the slack up in the belt tensioner. The only other thing that you will have to do is run a bracket from the back of your blower to somewhere on the motor to stop it from rotating around on the single mounting bolt. This can be from anywhere to anywhere, as long as it does the job. Mine was from one of the rear bolts that hold on the bearing-cap on the back of the blower, to a bolt on the intake manifold. That's about it as far as the installation goes. Other points to consider are plumbing the thing up (which should be accomplished by any decent exhaust/performance workshop). I got the original 4AGZE supercharger flanges laser cut and then welded some 2.5" mandrel bent piping for both the inlet and outlet. Also don't forget to hook up the two wires from the blower to a positive and earth somewhere. This is what turns the blower on (engages the Electro-magnetic clutch) or off. I use a switch in the wiring mounted underneath the dash, allowing me to turn the blower on (power) and off (stealth mode) whenever I need to. Make sure that you get your EFI computer remapped properly, other wise your motor will die real quick once you come on boost. If you already don't have one, you will need to obtain a MAP sensor that can read positive pressures (if your computer runs one) and get the whole thing remapped on the dyno to suite. A word of warning: you may run out of injector duty cycle with the standard injectors so beware!!!!! I was at 100% duty cycle at about 5500rpm on full throttle, so I had to change my injectors for higher flowing units. I eventually found, flow-tested and used some Nippon Denso injectors from a 3SGE 2 liter. These were a straight bolt in and flowed about 350ml per minute at 80% duty cycle with 40psi fuel pressure compared to 220ml per min for the standard 2TGEU injectors. You may want to replace your injectors BEFORE you go on the dyno to get the computer re-mapped, as if you find out that you run out of duty cycle before redline, then you will have to replace the injector with higher-flowing units and start the mapping all over again!! This is what I found and that costs even more $$$$'s. Ok, so now all this is done, what sort of power are we going to expect???? Well, that's tough to say precisely, but in my experience I went from 71HP at the rear wheels with my standard injected 2TG up to over 130HP at the rear wheels once blown. That works out to be about 180% increase in power out of an otherwise bog stock 2TG. No non-standard internals (except a bit of head porting) like pistons or cams, and even the standard 8.5:1 compression. That was pre-intercooler. I have since added a modified Lancer EVO IV intercooler to the front of the car to bring down those intake temps a bit more (like 70 degrees C!!). It has been re-mapped again with this mod, but no power figures as yet, but it feels HEAPS tougher.
That's about it, if anyone has any questions on this, feel free to e-mail me at frost@picknowl.com.au But until then, good luck!!