A/R Edumication

[ItsStockOfficer]

Originally posted by DrBrown
I think it changed the fuel pressure because the ecu leans out the O2 sensors to even the a/f mixture. In turn the ecu forces the FPR vaccum sensor thing to change which allows more fuel to enter the rails. I think thats it in a nuttshell.

I don't think there any way in hell your ecu could possibly affect the amount of boost reaching your fmu. I think this is just one more reason fmu's are ass.

Sean

 

[a351must2]

From what he's said, the AFC will not work on his computer because the VAM input is ignored past a certain point. This is true on Ford computers because they will actually max out the recordable airflow on the VAM and the computer will ignore that input and use pre-programmed tables from then on. In that respect, the Mitsubishi computers are a much more tuneable design and we should feel lucky.

DrBrown...you should search around on Stangnet.com...there's a guy on there with a 2.5L turbo probe that sounds like it runs pretty good. He goes by "TurboProbe" or something like that. He may even post on the TurboFord.Org forums, but they are not friendly to anything that's not a 2.3L SOHC Ford.

Also, the SDS is Simple Digital Systems EFI ... http://www.sdsefi.com/ They make a stand-alone EFI system for under $1K with no datalogging capability.

 

[DrBrown]

Originally posted by ItsStockOfficer


I don't think there any way in hell your ecu could possibly affect the amount of boost reaching your fmu. I think this is just one more reason fmu's are ass.

Sean

Thats not what I meant, I must have been unclear. The base fuel pressure N/A chages on hard driving only by 1-2 psi. But it has nothing to do with the FMU, we have a sensor on the stock FPR and the ECU semi-controls the fuel pressure using the senors return signal. If the computer feels the car is lean then it richens the mixture by dumping more fuel. Thats what I meant. And yes FMU's suck balls but its all I have for cheap. I can afford sds and I wouldnt know how to use it if I had it. Its getting the job done for now. Thanks for the help a351must2

 

[1fast4door]

a buddy of mine has a 2.3 quad 4 that's bored to a bit over 2.4 with a .48 stage 3 and a 46 trim in a .60 housing. his boost onset is as low as 1800 with full boost (7-8psi) at 2800. His pulls great all the way to redline, but i think he would benefit greatly from a larger setup (he of course doesn't believe me, but we'll see cause he just blew the seals on the turbo with over 120psi oil pressure anyways...if I were you, i wouldn't go any smaller than a .63 stage III or V . i like the 50 trim compressor on paper but great results have been had with 50,54,57,60 so i don't know if it really matters. For a 2.5 with a decent head design and low boost, have you considered the 60-1? I know that most people think its too huge but i think if you look at the comp. map you'll see that at low PR (1.4-1.5) the 60-1 is pretty good. of course then you would be creating a monster and i just reread your posts so maybe that is a tad big for your needs.

oh, one more thing... i realize that it's not a probe, but i have a lot of experience with the previously mentioned Quad 4 which is close in displacement and CR of a 2.5 probe so that's where i draw my opinions from. We just dynoed that Q4 with 320cc injectors at 7lbs. and in order to keep the A/F below 13:1 we had to add 48% of fuel above 4500 with the AFC (he also has a 12:1FMU). So basically what i'm saying is that bigger injectors might be in order. But then i realize that you have 6 instead of 4....so....nevermind i guess, i don't know what i'm talking about.

 

[DrBrown]

HAHA you dont know what your talking bout huh? Well it sounds like you know something about this matter. Anyway I had considered a 60-1 turbo BUT my goals are pretty modest. This is my daily driver and I want the engine to last another couple years. So my plan is to get the 57 trim compressor wheel in the 50 housing, and it has a 63 exhaust housing and stage 3 .63 turbine. This should be plenty of pull to reach 250 whp, which most ppl get 270+ on turbos slightly smaller than this. The 50 compressor will be fine for me since I am never going to run enough boost to be in a hybrids peak efficiency anyway so there's no need to go extra large :shrug: We'll see what happens when I get my turbo. Thanks though!

 

[a351must2]

Another reason I mentioned talking to someone that can match up a compressor for your engine is because of the existance of the 57 trim wheel...a lot of people go to the hybrid with the 57 trim wheel because of how cheap it can be had ($450 new)...they later find problems with compressor surge. I believe that's happening mostly on the stock headed 2.3L engines that just don't flow enough air at low rpm and high boost to stay right of the surge line, so it may not be a problem for you. (and I shouldn't mention the 3 guys that got brand new 57 trim hybrids that the compressor wheel would touch the housing when held over to one side.

 

[ItsStockOfficer]

Originally posted by a351must2
Another reason I mentioned talking to someone that can match up a compressor for your engine is because of the existance of the 57 trim wheel...a lot of people go to the hybrid with the 57 trim wheel because of how cheap it can be had ($450 new)...they later find problems with compressor surge. I believe that's happening mostly on the stock headed 2.3L engines that just don't flow enough air at low rpm and high boost to stay right of the surge line, so it may not be a problem for you. (and I shouldn't mention the 3 guys that got brand new 57 trim hybrids that the compressor wheel would touch the housing when held over to one side.

No, you shouldn't mention that because it has nothing to do with the trim of the wheel and everything to do with the machine work. So why not tell us who made these turbos.

And I agree a 50 trim is the optimal turbo for you.

 

[DSMJim]

Originally posted by DrBrown
I think it changed the fuel pressure because the ecu leans out the O2 sensors to even the a/f mixture. In turn the ecu forces the FPR vaccum sensor thing to change which allows more fuel to enter the rails. I think thats it in a nuttshell.

I think the nuttshell is that you need to get rid of your car, it's more hassle than it's worth from what I am reading. Buy a car that is turbo already and it will save you a lot of headaches!

 

[DrBrown]

Hmmmmmm NO . I love the way probes look, and I wont buy a turbocharged car and just upgrade it cause its easy. I love my car and I am not trying to run 10's or anything. A probe is better looking and more aerodynamic than 99% of the newer cars out there. Everyone and their grandma has a dsm so I refuse to be like everyone else just cause its easy to be fast. I will buy a 5.7 Trans Am if the money is right, but thats about!

 

[1fast4door]

Originally posted by DrBrown
This should be plenty of pull to reach 250 whp, which most ppl get 270+ on turbos slightly smaller than this. [/B]

My buddy got his car dynoed last week with the smallish 46 trim and only 320cc injectors w/ stock fuel pump (not enough fuel) on a 95degree day with no airflow to the IC and was able to get 220whp and 208wtq. This was all done with almost no tuning and a crappy pressbent 2.5" exhaust on 7psi. I think 250 whp should not be much of a stretch with your setup.

 

[DrBrown]

You are talking about a V6 probe engine right?? I wasnt sure about the 320 injectors, if its a probe those must be mazda millenia injectors. Also that sounds about like what I have now. I have the 45 trim t3 turbine and accordig to my trap speeds and 1/4 times I have about 220whp on 5.25 psi. So that sounds about right for what he is running. I would like to get to a dyno but my compressor seal is shot and I already bought a turbo. SO there's not much point in a dyno run when 50% of my pressure is leaking out of the turbo Thanks for the info though, he is doing pretty well for what turbo he has! Give him props from me. Its always nice to see other peeps getting themselves into stuff like this .

Dan

 

[1fast4door]

Originally posted by DrBrown
You are talking about a V6 probe engine right?? I wasnt sure about the 320 injectors, if its a probe those must be mazda millenia injectors. Also that sounds about like what I have now. I have the 45 trim t3 turbine and accordig to my trap speeds and 1/4 times I have about 220whp on 5.25 psi. So that sounds about right for what he is running. I would like to get to a dyno but my compressor seal is shot and I already bought a turbo. SO there's not much point in a dyno run when 50% of my pressure is leaking out of the turbo Thanks for the info though, he is doing pretty well for what turbo he has! Give him props from me. Its always nice to see other peeps getting themselves into stuff like this .

Dan

Actually if you refer to my previous posts i mention that i am drawing my knowledge/opinions from the Quad 4 my buddy has with the 46 trim on it. If you also look closer i mentioned that halfway thru one of my posts i realized probes have 6 injectors and not 4 like my example. so basically i was referring more to the airflow capabilities of the turbo to produce them #'s than the fuel and injector sizes as that differs significantly from my example to the turbo probe.

one thing though....how the hell did you fit a single turbo under the hood of a v6 probe? I've seen one online once with this crazy tube header but i assumed that was an extreme case. is that what needs to be done to turbo a probe gt?

 

[DrBrown]

HAHA if you only knew the hell of pipe building in a tight space like that! The whole thing took me almost 2 solid weeks of 12 hour days to finish it and get it running. The tranverse crossmember the bolts the chassis to the tranny needs hacksawed and made to where it has a "loop" area for the pipes to pass through. And the battery has to go. There have been couple different setups. Like mine with the battery relocated and mount it there, mount it under the battery, or have a custom deisgned exhaust housing that receives 2 inlets so you can bolt it to the front exhaust manni and have another inlet for the left side of the engine. Over all probes are GODLY under low boost. The 24-valve flow makes it shine. There are a handful of people with tuned turbo 2nd gen probes, and most of them push anywhere from 265-300 whp on 7-9 psi. And thats insane seeing as our engines push 132 WHP stock. SO its well over a 100% increase in power