Above is a picture of the ultimate turbo, that thing is a monster. If you have a car that can run this thing I dont want to race you.
The lower picture is of the T4 series turbo compressor. As you can see from the photo with the cd next to it, you get a good idea of what size it is. This is a serious upgrade for a turbo zx. You will need improved fuel management and much larger injectors then the stock 259cc injectors to run that kind of boost. This T4 compressor can produce up to 30psi boost with the right combination of compressor wheels and compressor housing A/R. I have a 2 1/2" inlet on my turbo, this turbo inlet I believe is 4" some serious Hp here folks. Picture comes courtesy of James, thanks James, the picture is a great visual aid to get things into prospective. When I installed my new T4 unit, I did a machup on my bench with the intake and exhaust. The compressor housing was about 1/8" from the exhaust manifold. I decided to get the 1/2" spacer from Turbonetics and move it away from all that heat. I also made a heat shield of aluminum as an added heat shunt due to the heat produced by my stock cast iron exhaust manifold. Cast iron that close to another part will have about a 90% heat transfer to the other part, maybe that is why they use them in boiler rooms and wood stoves. I made my own gasket out of copper and ported the inlet/outlet of the assembly. To finish it up I made a set of stainless steel studs, used flare nuts(15mm nut, made install easier over the 17mm nut, I could get to that hard nut on the top left side easy now)and spring washers in place of no washer or a lock washer. The install was very nice and I kept all the stock heat shields in place. I did have to cut a 2" X 1" corner off one shield to accomidate my new shield.
I have installed two turbo's on my car. The first was a hybrid Grand National compressor and the stock 280ZXT exhaust turbine and housing. The turbo spooled up very quickly, full boost at 2500RPM. I did like the spool up, however the power gains and drivability was a little much at times. The Grand National setup would give me boost levels of 16psi at maximum boost. I was running the stock Nissan exhaust system at the time with a 3" cat back and dynomax muffler. The turbo worked well and I would recommend it as an upgrade over the stock turbo. I now am running a TO4E 60 trim compressor and a modified stock 280ZXT exhaust turbine housing to accommodate the T4 turbine wheel. The housing is machined out to 2 1/2" for the turbine wheel.
I would suggest buying a book by Corky Bell, Maximum Boost before you decide to spend the money on a turbo. Upgrading your turbo is not a seat of the pants operation. There are so many opinions out there as to which combination is best. With Corky's book at least you will get an understanding of turbo operation and be able to make an intelligent informed decision. Installing an incorrect turbo setup is a costly mistake and you will be very unhappy with the operation and desired performance of your engine. I dont believe Corky's book is the end all on turbo applications, but there is a wealth of information in it.
A NOTE ON THE STOCK TURBO OIL FEED LINE:
The stock turbo oil line is a 3/16" Id line or so. The oil requirements of the turbo are well below this oil supply volume. Allot of builders are installing a .060 thousands orifice, and I have found some builders using a .030 orifice, in some fashion to restrict the oil to the turbo.
I have also noted in many cases with the higher capacity feed line, the turbo starts bleeding oil through the bearing and seal on the compressor side that ends up coating the intake system with oil that gunks up the entire intake system,( and I dont mean that cheeseball engine cleaner) the intake tubes and blowoff valve, intercooler, ect ect. The silicone couplers get very slippery and highly susceptible to sliding off under high boost conditions. Basically it just makes a mess, and one thing I really hate is a greased out to the max engine when I work on it. Like my uncle told me when I was a 3RD grade wrench, Spike, you dont have to waller in grease to work on a car, I took that to heart. Never did figure out why he called me Spike, but he had a white with black spider type webbing paint job, nice wide wheels and tires, totally killer 57 Corvette with a 427 big block Chevy, muncy 4 speed that would totally nail you to the seat, I LIKED IT, and it has been a hunger for power ever since. This was the man that gave me a three speed chevy transmission for my 2nd birthady, blew my mom's mind, she said she lost me for my second year of life, I was working on my motor. I still cracks me up everytime I think about her saying that. The man ruined me for life. My uncle Ralph has cost me allot of money because of that short joy ride in his Vette when I was so small. All I could see was that speedo, radio, all that chrome, my uncle running through the gears very fast, cool man, and that big flat steering wheel, hehehe.
Additionally, the excessive oil getting to all of the working parts of the intake system causes premature failure of the parts, so if you can use the smaller line, I highly recommend doing so, the turbo will be just fine.
I made my own line as the stock steel line was a pain in the butt removing and installing it, Also the banjo fitting is more susceptible to clogging on the turbo end of the line because of the heat at that point on the turbo. The stock turbo cartridge on the cars have only an oil feed. This type cartridge has a problem with cokeing of the lube oil(hardening of the oil and sticking to the cartridge and bearings) within the oiler passage in the cartridge which will cause failure of the bearings. The oil/water cooled (a turbo, termed as set up wet) units keep the cartridge much more cooler and alleviates the cokeing problem. A clogged banjo fitting screw is what took out my turbo in my car before I knew anything about turbos, cost me 450.00 to replace the turbo.
I decided on steel braided line in the -4 size. I pulled the oil pressure sensor and oil line junction block off the engine, tapped it out for a 1/4 NPT pipe thread. I also took the pipe fitting, drilled and tapped the hole in the bottom of the fitting to a 6mm thread, installed a bolt,(very tight) cut the overhang off, sanded the bottom of the fitting flat again and drilled to the size hole I wanted, and fitted my restrictor locally on the block end of the line. I then installed the oil block assembly back on the engine, ran the new -4 line and the job was complete. You will want to use the steel A/N fitting as the turbo gets a little to hot for the aluminum fittings in my opinion. Just a little trick I thought you might be interested in.
Final Build?
I am in the process of installing what I think will be the last upgrade for my car in the turbo application. I have developed very good power on the dyno, however the real power curve is short lived in my opinion. Looking at the dyno results, my power is dropping off at about 5300-5400 prm ranges. I am shooting for a power curve up to about 6800 rpm. I have two areas that need looking into to improve the power curve of the engine, the turbo and the cam. I decided to start with the turbo as I will need the additional flow to reach my goal of 600 horse power at the flywheel. The car is running almost to 500 horse power now.
My best guess from the dyno results is that I am running out of air flow at the higher rpm levels and that is shown from the drop off in the power at the higher rpm levels. The cam could also be the culprit, but I am thinking it is in fact the turbo.
The TO4E T3/T4 hybrid I am running now, and it is an excellent turbo, will be replaced with a unit that utilizes a 62-1 compressor wheel and a TO4E 60 A/R TO4E housing machined to fit the compressor wheel. The exhaust side will utilize the same exhaust turbine wheel, but I am changing out the housing from the .64 A/R housing with a Garrett .70 A/R housing. The .64 exhaust turbine housing was running very well on the car, good spool up and I decided to do a back pressure test before I removed the unit. I was very pleased to see that the back pressure only creeped up to 23 pounds, this reading was exceptional in the words of a number of people I spoke to about it. I decided to go a little bigger on the A/R because I felt the added 100 hp would push the back pressure to a level that would be to high in order to make the power on the top end rpm ranges. The only other option I had was to go with the Ford .82 housing (I really hate Ford anything on my car) but that would have required me to make modifications to my custom down pipe and I really did not want to mess with my work on the unit.
The turbo is almost ready for me and I will install it soon. I am thinking I will have about the same spool that I have right now. I am in full boost, 23-25psi @3000 rpm's, not bad at all I think, and I want to keep that number. One thing to keep in mind with a turbo application, is that generally, the bigger the turbo, the later it will spool. The T3/T4 hybrid turbo really is the best way to go as it does spool faster then a standard T4 unit. The only down side to the T3 exhaust side is that you may have a back pressure challenge when you get up into the 500-600 horse power range. I have spoken to a number of people regarding the back pressure issue. Corky Bell says no more then 2 1/2 times the back pressure as compared to the intake pressure for any turbo, but I think that when you start getting into the 40psi range of back pressure, you need to make improvements to lower that number.
The other factors that you need to keep in mind is the flow of the cylinder head. A large turbo will do you no good, except cost you some money, if the head and the exhaust manifold will not flow well. You need to exhaust what the engine takes in, so if you can get 200CFM into the head, you really need to be able to exhaust that same amount of CFM to have an efficient flow into and out of the head. I will keep you posted on the results of this new turbo, it's good points and its bad points.
Final Turbo Install
The Wastegate
Well they have finally come in. Here is a picture of the Tial 46mm external waste gate. This unit will bypass about 1.3 bar of exhaust. What this will do for the engine is enable it to run stock boost if I decide I want just stock boost of 7psi. I must say this is an excellent unit and appears that it will live a long and happy life. The Tile, unlike some of the other external waste gates is made of stainless steel on the exhaust side of the unit and aluminum on the actuator side of the unit. I am very impressed with it's construction. Note the large exhaust hole to vent the exhaust away from the turbo exhaust turbine.
The Turbo
Here is my prize. This unit is a special build I have come up with. The compressor is a TO4E housing 60 trim with a 62-1 compressor wheel. This should get me to where I want to go with this car.
Note the exhaust flange on the exhaust turbine housing. This is a Garrett housing with a .70 A/R The inlet to the housing is basically a T4, but with a T3 mounting bolt configuration. The divided inlet will help with the spool of the turbo.
The exhaust side of the turbo is a flange type setup with a V band to secure the down pipe to the exhaust turbine housing. I choose this configuration as it is much easier and simpler to make the modifications to my current down pipe for this turbo. I was also very pleased with the ability to clock the down pipe to make slight adjustments as needed. This configuration is much easier to remove and install then the stock Nissan flange configuration. No more making flanges for the turbo, no more worrying about stripped studs or nuts trying to remove the down pipe for what ever reason I need at the time. All the exhaust parts are stainless steel up to the flange off the turbo now, and easily changed.
Overall I am very pleased with this new setup. I believe it will prove to be an excellent upgrade for my car and get me to that 600Hp that I have always wanted to do with the car. This is going to be a killer setup and so easily installed and removed. I am going to have to do some of my custom work in the exhaust turbine housing area and in the compressor inlet area, but that should not be to much of a problem on a lathe.
hehehe, I cant wait to run the car with all of it;s new stuff.
The three turbo comparison
I have went and really jumped off a cliff on this one. Here is a picture of the stock turbo exhaust turbine housing on the right. The center is the turbo I just removed from the car. This turbo is pictured earlier. I got good results with this unit. I pushed the turbo to 27psi and it performed very well. I did not take it to its full output level as the car still needs tuning. This turbo is a very smooth unit. The boost builds well and it was not as radiacl a change when coming up on boost as the TO4E I was running on the car with the stock .63 A/R exhaust turbine housing on the right.
The turbo on the left is the new GT35R unit I bought and am now installing. This unit has a .82 exhaust turbine housing and a .70 trim compressor. I the wheel is larger then the 62-1 wheel utilized in the center turbo. If I had any doubts about the turbo in the center making 600hp, I dont have any for the new unit I am installing on the car. This thing is a monster. When I set both of them side by side I began to wonder if the compressor housing was going to fit under my intake manifold. I am still not sure yet, but I will get it to fit somehow LOL. So we will see how well the "ball bearing turbo" performs over the older non ball bearing turbo.
The exhaust manifold
I had to go with a new external waste gate because of the new exhaust turbine housing. I also at that time found out about a new exhaust manifold that a shop was making, so I decided to go with that for the better flow and the ease of installing a waste gate on the part. I had alot of work to do on the part when it came in, and I dont care to go into that one, but hee is the part installed on the car.
Here is a picture of the waste gate installed on the car. This gate works excellent. I am able to still maintain the stock boost pressure and get the high boost figures with the help a Blitz boost controller. This is the tial 46mm part and it was well worth the money and time. I think it turned out well, and it does all that I was expecting it to do.
InterCooler Tubes
