Just alittle question: How much boost will my stock (01, 2.5rs) MAP sensor read? I guess since its reading pressure, turbo size does matter.... so lets say on a 16g.
i'd think it could hold as much boost as that 16g could ever handle you shouldn't need one till you go HUGE....but then again im no mechanic...
We're talking about a '01 RS here, not a factory turbocharged car. So is the '01 running on speed-density like the '00? If so your factory sensor is completely useless in boost. It will hit the rail at 5v and your ECU pulls fuel, which is something you do not want happening under load, unless its going to pull all of it. Back in the day there was a supercharger kit from a company called Rimmer, and they got around the issue by using a voltage clamp to limit the voltage from the MAP sensor. You would most definitely need, at the very minimum, some sort of piggy back to make everything work along with a voltage clamp on the MAP sensor. This can often be an exercise in futility though. If you are considering using a 16G on your NA 2.5, you may want to wait untill you can get a real engine management solution, or do a WRX swap. Your motor doesn't exactly give you a lot of breathing room in the tuning department.
I've got some engine management going to be installed very soon.... Piddster, so wat your saying is that it wouldnt handle any boost at all?? I think i might be ok, I'm running 4psi through a tdo4. Boosts at 2500-2700 rpm and holds it until around 4000 rpm, when my engine starts to run lean. By this point, if I let off the gas the car will continue to accelerate and run within an accpetable air/fuel ratio. So, right now im purty sure i'm maxing out my stock rs injectors.
^^ LOL Scary, isnt it?! Thanks to flatline, the new 750cc injectors will be awesome!! **caugh** When i get my dtec installed
Its going lean because the stock ECU has no idea wtf is going on, and your stock 270cc injectors have little to no headroom for boost. Also, how do you know you are going lean? A crappy air-fuel gauge, or a real wideband? From the sounds of it, you might not even know what knock sounds like on a Subaru. Its not what most people think, in that it is a very faint tick tick tick, which is very easily overlooked. If you value your N/A 2.5 at all, you would not boost it without engine management and the proper equipment.
^^ I have forged internals, acl race bearings. Yes i have a real wideband and no i dont go out and run my engine lean all the time. I know why it runs lean, i just needed to know how much boost my stock MAP can handle and not your smartass comments.
I'm not being a smartass. Don't expect me not to think you are a noob when you don't post complete information on what you have going on. And I already answered your question. When you go beyond atmospheric pressure in the manifold of your speed-density 2.5 N/A motor, you are hitting the rail of the sensor (maxing it out) at 5v. So any boost and the computer does not know what is going on, and is pulling fuel. And forged internals do not mean the motor will hold up to knock.
yes yes , i know, sorry. Next time i will be more specific about my set up. Thanks for the info, I will have to pick up a 10v map sensor
will a GM 3bar map sensor work somehow? maybe we could wire that in somehow, MAP has them for like 70.00
The ECU has a certain transfer function that matches the factory MAP sensor. Installing a different sensor will completely throw it out of wack. Now, if you are using some form of piggy back or something that intercepts that signal, you can use your non-OEM sensor and then feed the ECU a "tricked" signal to get what you want out of it.
Tom, I have all the wiring diagrams for your ecu, why dont WE just wire in your DTEC..... I am more than confident that we can handle it....
