Topic: Another turbo jeep project... :^)

[CrashTestRacer]

So. I have a 97 TJ Se that is going to be taken off the road for a few months. I also have a mitsu T25 turbo thats not in use... You can see where this is going....
I have tons of experience building and rebuilding and tuning Mitsubishi, Toyota and Nissan, 2.0L turbo motors and have built several 350 hp 2L engines... as well as a junkyard ford escort turbo that has run 11.03 down the 1/4 mile last time out.. so im not new to engines or turbo systems... But I am new  to jeeps so forgive my ignorance on this subject. most of these are simple questions, and i will be doing my home work on this subject at the same time. so any one that can give me or point me in the direction of good info will be greatly appreciated..

the little planing i have done so far is as follows...
I have intercooler and exhaust pieing laying about so i will be fabricating a turbo manifold and down pipe setup out of scrap. i'm going to use a mitsu exhaust flange welded to the end of the custom manifold (the rest of the exhaust has yet to be determined.) The intercooling will be taking care of with the stock side mount intercooler from a 2g dsm side mount, maybe not the best option... but its cheap...

now heres where i need help.. how much can it all take?
 the t25 is a small turbo indeed but how much can the engine handle in the way of boost? I assume i am looking at new head studs and a head gasket to start off?
 Im assuming ill need new injectors off the bat, what about a fuel pump? will a 4.0L fuel pump do the job?
 Will the trans be a early failure point of the drive train?
and finaly engine management... i dont know crap about jeeps on this topic... educate me please

 I understand you probably get alot of questions from people who are enthusiastic about turboing their anemic 4 banger but dont understand the complexity of the project.. this is not the case. Im just asking for help in starting the information gathering, I dont expect you to do the research for me... so on that note any one who can chime in on the specifics or point me in the direction of useful information would be appreciated...

a little off topic but if i can find the pics Ill post the pics of the old CJ v8 swap with dualies that i helped with a few years back.

 
 
 

[chardrc]

if you go to the members projects area there are 2 threads about people who have / are turboing their 4bangers....  i don't know much of the specifics but you can get soem good information from the threads... good luck


http://4bangerjp.com/forums/index.php?topic=3560.0

http://4bangerjp.com/forums/index.php?topic=4115.0

[CrashTestRacer]

thanks a alot ill let everyone know the results if I get this done

[CrashTestRacer]

Ok still in the mental part of this build. when I start buying additional parts for this project (already have turbo, IC, BOV and FMU in the garage) I may start a new project thread..
Doing some reading and I have a rough sketch of what i will be doing for the map sensor. rather than try to deal with tricking the stock unit I will go with a programmable map designed for 5v systems.

The projects i have read up on are all Yj's, the fuel rail on the TJ has no fuel return!? So I'm not sure that I can even find a way to use a FMU... also where the heck is the pressure regulator? I know i could the fuel rail out for the one off the YJ (hypothetically) and run new fuel lines and that would allow me to run a FMU... but is that the best solution, is their a way to use the Tj fuel rail?

Jury is still on the fuel pump.. haven't looked into it yet. I'm making the assumption the stock 4 banger pump will not hold up and I feel like I'll either be looking at a 4L pump or the tried and true walbro 255.

The last pondering for the day comes in the form of turbo brackets... The builds i read had enormous mounting brackets that held the turbo to the block far from the exhaust manifold (Not criticizing, just curious and ignorant). why is it that no one is making manifold mounted turbos, (coming from a racing background here) in my experience the closer you can get the turbo to the exhaust outlet the better spooling and more efficient the turbo system is. I recognize that it would be a bit more work to re-make the manifold but it seems like it would be only benefits from their on out. But I am new to jeeps so maybe I am missing something...

[Jeffy]

Doing some reading and I have a rough sketch of what i will be doing for the map sensor. rather than try to deal with tricking the stock unit I will go with a programmable map designed for 5v systems.

Have you looking into making an Adjustable MAP sensor/Signal Modifier?  There is already one on the market but there are also instruction to make one as well.

The projects i have read up on are all Yj's, the fuel rail on the TJ has no fuel return!? So I'm not sure that I can even find a way to use a FMU... also where the heck is the pressure regulator?

You really need to get a Factory Service Manual.  Check the FAQ and see if there is anything there still.  The regulator is located on top of the tank.  They shoved everything back there.

Jury is still on the fuel pump.. haven't looked into it yet. I'm making the assumption the stock 4 banger pump will not hold up and I feel like I'll either be looking at a 4L pump or the tried and true walbro 255.

4.0L should be using the same pump as the 2.5L.

The last pondering for the day comes in the form of turbo brackets... The builds i read had enormous mounting brackets that held the turbo to the block far from the exhaust manifold (Not criticizing, just curious and ignorant). why is it that no one is making manifold mounted turbos, (coming from a racing background here) in my experience the closer you can get the turbo to the exhaust outlet the better spooling and more efficient the turbo system is. I recognize that it would be a bit more work to re-make the manifold but it seems like it would be only benefits from their on out. But I am new to jeeps so maybe I am missing something...

The biggest hurdle is the manifold.  No one makes one.  I've though about having an adapter made that will connect to the existing manifold coupler though.  That would put the turbo pretty close to the manifold without having to spend big bucks on a custom manifold.  The only down side is that the turbo is mounted low.  Most likely at the bottom of the block or even oil pan level.  The problem with this is that most people here are taking them offroad.  So mounting the turbo high up has a clear advantage in that sense.

[CrashTestRacer]

I would assume that making an adjustable map sensor would employ the use of a potentiometer. Their are also some tick computer programable units out their that would allow for more precise tuning. The running total of this project when I get to that point will likely determine which I get.

Your right I really do need to get a FSM... As far as jeeps go Im still illiterate.. but I'm learning fast 

Thanks for the info on the fuel pump, given that i would assume the radiator would also be the same for the 4L and the 2.5?

As for the manifold I was planning on making one my self , I mean your already doing the whole custom turbo thing, why not mount it where it will spool best? You make a good point about having it low in the engine bay. But at the same time, unless your  smashing your oil pan on stuff it shouldn't be a problem. Rear mount turbos get wet all the time so thats not an issue and you can mount the filter as high as you want in the engine bay, or even snorkel it if you want..

[Cyborg]

The last pondering for the day comes in the form of turbo brackets... The builds i read had enormous mounting brackets that held the turbo to the block far from the exhaust manifold (Not criticizing, just curious and ignorant). why is it that no one is making manifold mounted turbos, (coming from a racing background here) in my experience the closer you can get the turbo to the exhaust outlet the better spooling and more efficient the turbo system is. I recognize that it would be a bit more work to re-make the manifold but it seems like it would be only benefits from their on out. But I am new to jeeps so maybe I am missing something...

I also thought about making my own manifold, but after really thinking it through, with the ammounts of rocks, mud and water I put my rig through, it just seemed like I was asking for trouble.

An oil line snaps off, and you dont realize. . . bye bye engine and turbo
mud caked around the turbo
breaking/snapping/removing an air pipe and sucking dirt/water/mud

[Jeffy]

Thanks for the info on the fuel pump, given that i would assume the radiator would also be the same for the 4L and the 2.5?

As for the manifold I was planning on making one my self , I mean your already doing the whole custom turbo thing, why not mount it where it will spool best? You make a good point about having it low in the engine bay. But at the same time, unless your  smashing your oil pan on stuff it shouldn't be a problem. Rear mount turbos get wet all the time so thats not an issue and you can mount the filter as high as you want in the engine bay, or even snorkel it if you want..

Well, if you plan on actually wheeling the Jeep, it can be a problem and a big one at that.  Just check out the trail forum and you'll get an idea of what we do.  A little bit of water isn't a problem but when you're submerged then that can become a problem if it's not all sealed.

Forgot to mention, the radiators are a bit different.  The 2.5L's are usually one large core or two core.  The 4.0L's are usually 2-3 core.