Last month I decided to try my hand at building a custom turbo setup. I looked at buying a KKK turbo and manifold because it was pretty much bolt-on, but I was turned off because the turbos and manifolds were hard to find and relatively expensive. I ended up deciding to use a Mitsubishi TE04H turbo and build my own manifolds. The TE04H seems to be inexpensive, really easy to find, is small (no turbo lag) and has an integral wastegate; just what I was looking for. Here’s how I accomplished it:
I purchased a TE04H turbo for $99 (see picture), and found another one locally on a wrecked car that I got for free (spare). I also purchased some silicone elbows, oil cooler, 0-15psi boost gauge, boost controller, misc. fittings and steel braided hoses, and a hood scoop.
I made the flanges for the downpipe and exhaust manifold simply by tracing around the turbo with a piece of limestone on ¼� plate steel and following the lines with my plasma cutter. I used the old exhaust manifold as a pattern for the head flange and cut it out the same way (see picture). I bought a bunch of 1-1/4� schedule 40 steel elbows and welded together the exhaust manifold. I kept the flanges bolted to the original manifold to prevent warping, but I still had to drop it on the belt sander when I was finished to straighten it up.
I took the turbo apart and clocked it to keep the oil supply and drain ports in the right place. It took some time, but really wasn’t very complicated. I’ve never had a turbo apart so I took my time to make sure I didn’t screw anything up; but it wasn’t too difficult.
I tapped out the oil filter adapter to supply the oil for the turbo, and then installed the oil cooler in the scoop on the hood (see picture). I was worried about the scoop looking stupid, but it was the only place I could mount the cooler where it would be safe and have adequate airflow. I think it turned out OK…not exactly my kind of thing but I don’t dislike it either. The oil gets cooled before it enters the turbo (I hope this will reduce coking and help the turbo live longer). I tapped a drain line into the oil pan and hooked it up to the turbo.
The TE04H is water cooled, so I just installed it in my heater line, before the heater core. An unexpected benefit is that the heater works better now…
I had the local exhaust guy bend up some 2-1/2� tubing for the turbo supply and air filter lines. I’m planning on powdercoating them at a later time…
I installed the boost gauge next to the pyrometer in the dash (see picture) and plumbed it into the intake manifold. I also used the same port on the intake manifold to supply the boost controller and wastegate (see picture).
I started it up last week and did a little tuning. I was able to turn up the fuel pump quite a bit without a big increase in EGT’s; the turbo allows the engine to burn a lot more fuel than when it was naturally aspirated. I set the boost controller for 7-8psi of boost. It reaches full boost around 1000-1500RPM (I don’t have a tach installed). I have put about 500 miles on it since I got everything set up; here are my impressions:
• I gained a LOT of low end torque; I’m guessing about 40 ft-lbs. I also got some high-end power, though it isn’t as dramatic as the low-end. The seat of the pants feel is amazing…I’m guessing that the sami accelerates more than twice as fast as it did without the turbo. Top speed is now 65-70 in 5th gear on flat ground. Still no race car, but pretty darn good for a little tiny diesel motor.ÂÂ
• There is very little turbo lag; it reaches full boost right away even at low RPM’s.ÂÂ
• Climbing the hills out here is no problem; it holds 55 just fine as long as I care to hold the pedal on the floor. Unfortunately, if the climb is too long, my EGT hits 1200 degrees after a mile or so and I’m forced to back off and let it slow down to about 45MPH.
• The turbo sounds cool; with no insulation in the engine compartment it is quite audible at all speeds. I don’t mind one bit and intend to keep it that way.
• The engine runs at the same temperature it did before I added the turbo; no problems with overheating
• Except for a puff of smoke while the turbo is spooling up, the exhaust haze that the motor had without the turbo is completely gone.ÂÂ
• I don’t have good mileage numbers yet, but I am getting about the same as I did before the turbo.
• My opinion is that this is a better swap for a trail rig than the 1.6L Suzuki because of the amount of low end torque the diesel makes. For a rig that sees mostly highway, the Suzuki engine may be better because of the higher HP numbers. I have driven a few samurais with 1.6 8v and one with a 16v and can honestly say that I personally like this turbodiesel better.
This project took a huge amount of time. I hate to admit it, but it really probably wasn’t worth the time I put into it. If you figure my time at $10/hour I could have almost bought two 1.9TD engines. The biggest problem was that I had never done a custom turbo project before (and had never done any major work on any turbo engine). I ended up backtracking a lot and making a few mistakes that cost me some time.ÂÂ
Would I do it again? Yep. I have the only Suzuki samurai with a VW diesel engine with a Mitsubishi turbo out of a Chrysler car with Toyota steering with a GM alternator with a corvette scoop on the hood. But, it works quite well and I am happy with it.ÂÂ