SR20 Forum banner
1 - 9 of 9 Posts

·
www.motorists.org
Joined
·
3,047 Posts
Discussion Starter · #1 ·
This was originally from me to my dad since he is currently very nervous about the whole thing since he doesn't have nearly the understanding of the process as I do. I edited it a little bit and thought it would be good for ANYONE interested in installing a turbo on their car to read, as well as Eric to read so he gets a better idea of what's in my head about the install. Enjoy


This is LONG. You will probably want to print it out


In order to turbo a car with the stock 9.5:1 compression SR20DE motor using the Nissan parts off of a Bluebird SR20DET, the mandatory parts are:

-the turbo itself (it's called a Garrett T25)
-the exhaust manifold (the 4 into 1 short pipe from the engine to one side of the turbo)
-exhaust pipe from the turbo outlet to the catalytic convertor (guess you don't really NEED this, but if you want it to be relatively quiet, not coat your engine and underbody with soot, and not be a gross polluter, then you want it
)
-air filter and intake piping to the turbo center section to suck in air to be forced into the intake
-piping from the turbo to blow into the intake manifold (with an intercooler in the middle of that piping)
-a blowoff valve to release the built up boost when you let off the throttle
-higher flowing injectors to flow enough fuel to compensate for the added air the engine is getting (stock are 259cc, the ones I have are 370cc)
-a custom ECU (computer) to control all this

Those are the ESSENTIALS in order to have boost. Boost is the amount of air pressure added by the turbo into the intake manifold to increase power output. More air plus more fuel equals more power. FYI stock boost for the Bluebird SR20DET system is 7psi. Next are the recommended parts so you can monitor what is going on as well as make your turbo system more efficient:

-boost gauge to make sure your boost level is where it's supposed to be. Else how would you know if your wastegate was stuck open and you were hitting 18psi until your engine blew?
-Exhaust Gas Temperature (EGT) gauge to monitor your exhaust temps to make sure you aren't going to melt your cylinders. Also helps you in tuning your car to get the most power you can with safe exhaust temps.
-Air/Fuel ratio gauge to make sure you aren't running too lean or too rich (too lean=hot melting cylinder stuff- bad. too rich=cooler cylinder temps, but less efficient power, more fuel consumption, car may not run as well)
-3" mandrel bent exhaust. Turbos like zero back pressure. The less back pressure, the more freely they can spin, therefore making more power, expelling the exhaust heat faster and easier, and creating less reversion during cam overlap. (wow, really starting to sound like I know my stuff huh?
) Also the smooth mandrel bends help exhaust flow characteristics. Here are some links on the advantages of mandrel bending over crush/press bending pipe:
http://www.extrememotorsports.com/mandrel.htm
http://www.bobsmuffler.com/manb.htm
http://www.bobsmuffler.com/mandrel.htm
-mandrel bent intake and turbo piping- same reasons as the exhaust- better flowing means better boost spoolup, throttle response, and a tinch ultimate boost
-turbo timer- a simple electronic box that keeps your car on for a few minutes after you take the key out so hot engine oil doesn't sit and bake in the ultra hot turbo and ruin the turbo

After that we get to the hardcore performance stuff:

-boost controller- the wastegate that is integral to the exhaust side of the turbo opens gradually from 0psi to 7psi to make the boost come on slowly and smoothly. At 7psi it is open all the way and that keeps it at 7psi. This controls the boost is makes and is connected to an actuator solenoid. The boost controller is an electronic device that connects to the actuator solenoid and keeps the wastegate fully closed (using electronically controlled vacuum) until a psi level that you set occurs and the boost controller throws open the wastegate at that moment to stop the boost from increasing further. This does several things to increase performance. First and foremost it lets you increase the maximum boost level over the stock level for a higher level of power output. Second it keeps the wastegate completely closed until the preset point, thereby building boost faster than the manner in which it functions stock, gradually opening the wastegate until max boost.
-Ford Mustang Cobra Mass AirFlow (MAF) sensor: The stock MAF on the SR20DE can only measure about 220hp worth of air. If you increase the boost such that the MAF is maxxed out and it can't measure any more air, you get a LOT more air than what the MAF is telling the ECU is telling the injectors how much fuel to spray, so you lean out the mixture A LOT and melt your pistons. Not good. A Cobra MAF can measure a lot more air than my T25 can blow, well over 300hp. To install this you #1 need to get your ECU reprogrammed by Jim Wolf Technologies (JWT for short) and #2 you need to get the harness adapter for the Nissan MAF plug to go into the Cobra MAF. Then you can turn up the boost even more.
-Dunno if a T25 can make enough power to necessitate this, but JWT makes a custom high horsepower fuel rail that flows more fuel to the injectors. At this point you would need even bigger injectors, I believe the next step are 555cc injectors. Also at some point you would need a higher flowing fuel pump. I'm not really versed on that far up on the power scale yet.



NOW- FOR MY TURBO PROJECT- THE INSTALLATION ORDER AND PROCEDURE:

#1: Get all the above stuff well ahead of time!!!

#2: Drill and tap the block for the turbo's oil return line. DONE
#3: Install JWT ECU and 370cc injectors. Any ECU is programmed for a specific injector. Cross programming with the wrong injector and either your car runs like ****, doesn't run, or worse.
Installing these items is very safe and recommended to do ahead of time because you know if the ECU and injectors function properly before installing the hardcore turbo stuff. Therefore you have a better clue of where problems may lie if you have problems since you are doing the install in more steps. Also, since we have the throttle body off to install injectors, we will consult the Factory Service Manual (when I get the right one) to find out where the coolant goes through it so we can bypass it and prep the lines to route that coolant to go through the turbo instead of the throttle body. The reason coolant goes through the throttle body in the first place is to warm it up in cold cold winter so that the throttle plate doesn't freeze or something like that. Just gotta make sure I warm her up good I guess. Dunno if it will be an issue or not. Ah well. Not like I have a choice.

#4: TURBO TIME! Ok, first thing is drain the oil so it doesn't get messy when we pull that plug from the block. Also drain the coolant. Actually now that I think about it, it would probably be ok to do the coolant flush and fill when we do the ECU/injectors/throttle body coolant bypass since more coolant will be thrown about at that time. We remove the "secondary" header pipe, the one that was hanging when we did the oil pan that connects to the catalytic convertor. Will buy some PB Blaster (rusty bolt freer upper) to easy that removal from the cat. We can also redo the oil pans at this time. Then remove the primary header/exhaust manifold from the block. Clean up the block and turbo manifold mating surfaces. *Attempt* to port match them. If it is not feasible then oh well. With the gasket I have bolt the exhaust manifold w/turbo attached assembly to the engine like a header (cuz it is one basically, just has a turbo stuck in the middle of it
). Connect the turbo oil drain line to the hole we made in the block. Depending on the completing level of the oil pan stuff, bolt on that "secondary" pipe I've had sitting in the corner of the garage. There could be the potential of fitment problems with that pipe because it was made for the previous generation of Sentra. We SHOULD get under the car and eyeball it a bit to make sure it's going to be close. Haven't done that yet. Assuming that's ok and bolted on, we move on to the oil feed line. We T off of the oil pressure sending unit in the back passenger side of the engine bay and bring the host all the way around the driver's side back of the motor around to the front and connect it to the turbo oil feed line. Eric will know how to do that easily because he has T'ed off that sending unit to install his oil pressure gauge, so with him there it will be a snap. Two lines we will need to cut off and flared since they are those O connector things that normally screw into the DET block, but my block doesn't have simple provisions for those (would require more drilling and tapping, and I wouldn't want to because I'm not sure where the shavings would end up since the boss's are much higher on the block). We will have already prepared the coolant lines so we just uncap them and connect them.
Almost done! Next is the "easy" stuff in my mind. All that is left is to mount the intercooler and create the piping for it and the intake to the cone filter. So first we fit the intercooler (IC for short), cut the bumper minimally to let it fit, get the hose we need (hard metal hose- the more the better- need to use the least rubber we can and the least bends to maximize flow), attach it to everything (that's a big step in making the custom piping btw). Thought about "Why not use PVC pipe?" but, at least from the turbo to the IC that air will be HOT so PVC would not be safe. Have to use metal and rubber. Get that all done and all that's left is connecting the various vaccum lines that go various places.

Make you you put fresh oil in, run the starter without the sparkplugs, fuel pump fuse, and the two electrical connectors removed from the distributor, for 60 seconds to get oil pressure back thru the engine and thru the turbo, especially since we just did the oil pan thing again. Put the plugs, fuse, and electrical connectors back in.

AND THAT, MY FRIENDS, IS A TURBO INSTALL.
GO TAKE HER FOR A WILD RIDE!!!!!!!!!!!!!!
 
G

·
if you buy a DET you would be ahead of the game.i bought a DET and put it in my sentra SER,used the SER harness with the DET ECU and air flow meter, turned the boost up to 15psi,now i'm running 12's all day.do it right from the beginning and you won't be sorry.
 

·
_______
Joined
·
3,640 Posts
Hey! My keyboard is working again
Ben dose this mean you have the turbo running????? How do you like it?

I just got my MSD/JWT/Cobra maf fuel set-up going and it like a totally diffrent car. Not only can I run more boost but the car just seems to be faster even at 8psi than it was before. More fuel?... more power.

Mike
98sentraSE Turbo
01 Sentra GXE
 

·
pwnd
Joined
·
3,455 Posts
Hey Ben when are you doing this again? I know you said Eric may be coming up to help ya. I might be able to also. Just depends on the date and how much it will cost me. If you want another set of hands let me know I might be able to give some help. Think you said around Thanksgiving. I just need to know when and how long. Know dad wont mind hell i just went home friday for the first time the entire semester and dont plan on going again for a long while.

LOL seems like Im driving to help people now
Going down to Columbia TN next weekend to help a friend do a tune up and new timing belt on his Ranger. So I might be willing and able. Like how far is it from Nashville to your place?
 

·
www.motorists.org
Joined
·
3,047 Posts
Discussion Starter · #5 ·
QuickSER- How much can the DET MAF flow? How much was it? Wonder if it's an decent alternative to the Cobra MAF? And the 370cc injectors are good enough to pull 12's? Didn't realize one could push that much power with a stock DET and not go boom. Do you have a front mount IC?

Mike G: No, definitely don't have it on yet. That was just a description of my plans a month from now. I do have the boost gauge installed now. Can't seem to get above zero though. That will be remedied shortly


Bowlcut: I am completely off of work and school from Wednesday the 22nd thru Sunday the 26th to do the install. If you wanna come too, sure I've got space
For all this kindness and good help you can sleep in my bed and I'll go have the couch.
Nashville to Lafayette is right at 350 miles. If you wanna show up as early as Tuesday night at 8:30PM I'll be home since I have class til 8. Doesn't look like Eric can get here before sometime on Friday so if you can get here earlier that would be excellent. Let me know!

[Edited by Ben98SentraSE (10-08-2000 at 04:44 PM).]
 
G

·
I'm sorry I didn't reply earlier but I forgot my password. I'm running the DET from the PulsarGTIR so I have 440 injectors. The air flow meter looks almost the same as the regular one but the sensor is different.I couldn't use the SER AFM with the Pulsar ECU. I took the stock Pulsar intercooler and repositioned it to the front of the car. It flows good (at least good enough to run 12's at 15 lbs. of boost.
 
G

·
nice,set up..tip: you need a NX2000 radiator because the se-r one is to small..the NX2000 one is double core......OR YOU WILL OVER HEAT......
 

·
_______
Joined
·
3,640 Posts
Not really true. I have a DET in my 98 SE and I have the stock radiator and ur pullies. I beat the **** out of it in 90deg weather sitting in traffic,clumbing hills hauling 4 fat people around,drag racing..etc. not once has the needle even risen from mid range.

The NX's on the other hand seem to have less radiator breath area and a prone to over heating with the addition of a turbo.

Mike
98sentraSE Turbo
 
G

·
Here in Florida it gets real hot, but the stock radiator is doing the job. The only time my needle ever went past half was when I was showing my friend that my car could hit 150mph,when I slowed down it went right back down to halfway.
 
1 - 9 of 9 Posts
Top