So I decided to buy my first 240sx for a project I've never owned a Nissan before but I figured its worth a shot so I bought a series 1 rb25det. Now I have a few mods like.
Greddy intake mani
Cxracing intercooler
Tail 50mm bov
Jgy fuel rail
850cc low independence Injectors
Xo2 top mount turbo mani
Tail 38mm wastegate open dump
3in turbo back exhaust
Gt35r .72 ar
Cxracing aluminum radiator with slim fans
Walbro 255
Aem wideband
Aem tru boost
Mckinny mounts
Mckinny drive shaft

Now I'm trying to accomplish around 400-450whp but I've been trying to figure out what to do with tuning. I honestly have no idea what to buy and my funds have dwindled since I started this project I would like some opinion's. Can I just use nistune or a power fc to do this and what would be better any advice will be greatly appreciated

Well looks liek you are ont he right track. Few questions though, why do you have low imedence inhjectors? I thought the RB uses high imedence. I may be wrong bu tif you use low impedence u are going to need resistors. \

And why the power fc? There much better tuning options for the RB. The PFC is good when you get it up and running but will end costing u just as much a s AEM or Haltech after you buy a dataloggit or tuning software for it. And those systems are much better and more modern.

I honestly didn't know what to buy for Injectors and I got a really good deal on them. do you think if I buy resistor's they will be suitable for my build. As far as tuning goes I was looking into haltech because I heard good things but there really expensive and I wouldn't even know what model to choose and if I would have to change any sensors like I would with aem I'm completely stumped?

LOL you got a lot of learing to do but no matter thats why we are here. After a little research your RB25 injectors are side feed high imedence. Meaning that you will have to wire in resistors in each power wire (not ground) for each injector to run low impedence top or side feed. As far a ssize the should be good 850'ss are good for over 500hp no probelm without running to high into duty cycle.

Yeah haltech would be great for you build. The new ones are plug and play and all you have to do is install a IAT sensor and a MAP sensor really nto hard. Also you just buy a engine specific model. So in your case you would buy a Haltech E11 for the RB25 engine.

Also the walboro fuell pump might be a little small for you app maybe get a inle 044 boach pump as well. Your turbo choice looks good everything esle looks legit. Just do good work and research and read on your own. You will learn a lot.

I really appriciate the help i guess im just going to have to save for a little bit for the haltec. I ended up running out of cash fast i couldnt believe how expensive things are for that engine haha. So once i end up getting the haltch I just have to find a tuner for haltech to get my car tuned right?

What do you think about micro tech?

oloo wrote:What do you think about micro tech?

Micro tech is also a good EMS. I have never used it but people seem to like it a lot and is definitely a capable EMS. Just make sure it will work with the RB25. I like AEM and Haltech because they are plug and play. Micro tech may need you to run a new harness but again i really don't know.

oloo wrote:I really appriciate the help i guess im just going to have to save for a little bit for the haltec. I ended up running out of cash fast i couldnt believe how expensive things are for that engine haha. So once i end up getting the haltch I just have to find a tuner for haltech to get my car tuned right?

Yeah pretty much. But first thing is first. Clean up the motor. New seals/fluids everywhere, including the tranny and diff. new plugs, check compression and leak down if you can. Get all your supporting mods installed properly and cleanly. Get the motor in and fire her up should come with a stock ECU which will get the car to start just dont go beating on it.

With the motor out is a good time to clean up the engine bay. Take anything out you won't need. Also if your going ith a short throw shifter or solid motor mounts nows the time to do it. I personally dont like short throws or solid motor mounts so it up to u, im just letting you know.

Also with the motor out you might wanna think about head work, cams springs retainers, maybe a new headgasket. But with your power goals the RB s should hold together just fine. RB25 can put 500hp down without breaking a sweat in stock form without anything but a turbo and tune.

Once in the car wire up what you need, your boost controller and wideband. Check timing and fire it up. Get your new EMS installed and bring it to a tuner. Not just any tuner ask around and research. Look for the tuners shop race cars. Almost every shop worth it's salt will have a shop race car. Ask to speak to prior customers and ask around on forums. I know all the good tuners around my area, soon you will too.

One thing i can't stress enough is to have your car in tip-top shape before the dyno day. Make sure the little things are buttoned up. Things like a bad fuel pressure regulator, or bad boost controller wiring or even a mysterious vacuum leak can ruin your dyno day. Have everything in order, and take your time. This will save you a lot of money and headaches.

Oh and i also suggest a oil catch can for your setup, that turbo is going to pushing a lot of blow by.

Ok so I found a guy that's selling a micro tech lt-16x for 900 shipped. he used it for his r32 with a rb26. He said it comes with a premade harness from micro tech and the only thing I would need is a rb26 Injector harness and Injectors and its pretty much plug and play so to speak besides having to hook up an entire harness I don't know if that's a good deal and it sounds kind of off.
I thought the rb25 and rb26 were completely different as far as sensors go. should I be a trusting fellow or what?

oloo wrote:Ok so I found a guy that's selling a micro tech lt-16x for 900 shipped. he used it for his r32 with a rb26. He said it comes with a premade harness from micro tech and the only thing I would need is a rb26 Injector harness and Injectors and its pretty much plug and play so to speak besides having to hook up an entire harness I don't know if that's a good deal and it sounds kind of off.
I thought the rb25 and rb26 were completely different as far as sensors go. should I be a trusting fellow or what?

Running a harness is a pain in the a**. But your going RB and your going to have redo a lot of wiring anyway. So you would be wiring your RB harness to a s14 chassis or this EMS harness to a s14 chassis. As far as the injectors idk, i mean you going with top feed low impedance anyway so why would you get different injectors. Unless you wanna sell those and get side feed high impedance ones which would be much less of a hassle. Also your going to have to wire your cluster and gagues up. As far as price it seems to be decent. 900 is good for any EMS thats not a Power FC. But again your goin to be doing a lot of wiring and i don't know how comfortable you are with that.

I advocate doing all the work yourself. Or find someone how is willing to hold your hand while you do the work. It makes for a very educational experience, after a year of DIY you will be very familair with RB and many other nissan motors. Plus a shop will put u in bankruptcy.

Dont be to rash about the EMS. Look around and research. See what seems like a good fit for you and wait a couple of weeks just to see whats out there. The classified here have a RB25 ems for sale at least once a month. So just be patient and get your build in order.

not to be rude, but if this guy is only wanting 400 -450 wheel for a hobby car why are you steering him towards a 1300+ ECU instead of the simple PFC or even a $420 nistune? I get the feeling most the tuning will be done professionally, so user interface/learning curve wouldn't even be his problem. lightening MAFS are supposed to be good to 450WHP

I ended up buying nistune and had a problem with it so I bought a pfc. Its currently awaiting for me to pick it up at the tuner and made 514whp and 542tp @ 16psi. All's I plan to do with the car is race it on the weekends haha.

I got a similar setup in the works. You didn't use arp studs? What about ur hg? I'm very interested to see how your internal setup is holding up if its stock at that much hp. Would be nice to know I won't need to buy these things yet if your is holding together lol