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1993 ls turbo
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Sure, the drivability issue Im having I believe has to do with a stock Naturally aspirated tuned ECU running boost and the wide range of Air Fuel values it's seeing. Sometimes the car will run great. When it's at idle it sees Vac and knows no different that its on a boosted engine. When the car is on boost the RRFPR adds the extra fuel needed by boosting fuel pressure and keeping the AF ratios at a safe level with the higher than desired Compression ratio of the engine. So on boost and at idle the car runs like it should. BUT! The issues Im having are at part throttle, regular driving scenarios where the car is not at idle nor am I giving it enough throttle to go into boost. Since the turbo will add enough extra air to remove the Vac the engine sees alot of extra air, the AF ratios seem to jump wildly at these part throttle applications. Leaving an intersection or stop light and the car will buck and jump as the AF ratios go through bad ratios to good ratios where the engine can make power. The ECU doesn't seem to have the range to deal with it. Not enough air to make boost but to much to see Vac and it freaks out. I've had to learn how to drive it to avoid those high AF ratios, and it's like drive it like its stolen. This winter it seems the car runs alot smoother in the cold air. But Im looking for something that will drive like a stock boosted car. So Im looking to ditch the RRFPR and get a standalone.


Im maf . Probably apples to oranges here but im running a holly rrfpr with a needle valve to fine tune the afr. And it runs awesome. And is predictable. Maybe its your rrfpr or something on your map side of things? The only thing that affects my driveability is a good tmic heat soak in summer weather. Im running 12 psi and up to 16psi using water injection until i can adjust timing
 

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99 22B replica
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My car is MAF also. I didn't know Holley made an RRFPR. I still want to rebuild for higher boost and get a tuneable ECU. What rate of fuel pressure boost are you using to get 12psi? My Vortech is 6:1. I have read the stock injectors can lock up shut close to 100psi fuel rail pressure. You must be getting close to that?
 

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1993 ls turbo
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also. I didn't know Holley made an RRFPR. I still want to rebuild for higher boost and get a tuneable ECU. What rate of fuel pressure boost are you using to get 12psi? My Vortech is 6:1. I have read the stock injectors can lock up shut close to 100psi fuel rail pressure. You must be getting close to that?[/QUOTE]

Im not sure what the rate is. Im running no plates and air bleed almost wide open to lean it out enough. Im not running a fuel pressure gauge . Theres no lack of fuel. Using dohc redtop injectors. I had som jdm sport ebay crap rrfpr frome mirage sports it was not worth its weight in scrap. The holley unit is quality
 

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Sure, the drivability issue Im having I believe has to do with a stock Naturally aspirated tuned ECU running boost and the wide range of Air Fuel values it's seeing. Sometimes the car will run great. When it's at idle it sees Vac and knows no different that its on a boosted engine. When the car is on boost the RRFPR adds the extra fuel needed by boosting fuel pressure and keeping the AF ratios at a safe level with the higher than desired Compression ratio of the engine. So on boost and at idle the car runs like it should. BUT! The issues Im having are at part throttle, regular driving scenarios where the car is not at idle nor am I giving it enough throttle to go into boost. Since the turbo will add enough extra air to remove the Vac the engine sees alot of extra air, the AF ratios seem to jump wildly at these part throttle applications. Leaving an intersection or stop light and the car will buck and jump as the AF ratios go through bad ratios to good ratios where the engine can make power. The ECU doesn't seem to have the range to deal with it. Not enough air to make boost but to much to see Vac and it freaks out. I've had to learn how to drive it to avoid those high AF ratios, and it's like drive it like its stolen. This winter it seems the car runs alot smoother in the cold air. But Im looking for something that will drive like a stock boosted car. So Im looking to ditch the RRFPR and get a standalone.
What an excellent, well worded answer. Thank you :)

So right now I'm running the stage 2 delicious tuning reflash, so maybe I can get him to add fuel at part throttle. Or do it the hobo way and adjust my base fuel pressure up a tiny bit (2-3 psi), and run a lower rrfpr ratio (6:1 instead of 8:1).

I wonder if it'll have the same impact on my car since I'm MAP not maf like you....
 

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99 22B replica
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I've read the guys with MAP cars need a higher ratio RRFPR than MAF cars. I run a 6:1 ratio and get 11:1 AFs in boost, which is pretty good. If you've got a stage 2 reflash wouldn't that be for NA and more aggressive timing? I wanted to get Bill from delicious to retune my 99 ECU for boost like he said could be done but after a few back and forths I couldn't get him to say "yeah send it to me." Then I couldnt even get a response from him. So that's why Im looking to go standalone. I think that's a much safer and upgradable setup.
 

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I've read the guys with MAP cars need a higher ratio RRFPR than MAF cars. I run a 6:1 ratio and get 11:1 AFs in boost, which is pretty good. If you've got a stage 2 reflash wouldn't that be for NA and more aggressive timing? I wanted to get Bill from delicious to retune my 99 ECU for boost like he said could be done but after a few back and forths I couldn't get him to say "yeah send it to me." Then I couldnt even get a response from him. So that's why Im looking to go standalone. I think that's a much safer and upgradable setup.
Super aggressive timing. I'm going to ask for stock timing (actually, pull 2 degrees between 3-4k, pull 4 between 4-5k, and pull 6 between 5-5.8k). I'll also get my limited brought downto 5800rpm (I didn't make power past that anyway).

My original idea was to run an 8:1 and get the 10:1 disk just in case.
 

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2001 Impreza 2.5RS Sedan
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Super aggressive timing. I'm going to ask for stock timing (actually, pull 2 degrees between 3-4k, pull 4 between 4-5k, and pull 6 between 5-5.8k). I'll also get my limited brought downto 5800rpm (I didn't make power past that anyway).

My original idea was to run an 8:1 and get the 10:1 disk just in case.
Like flyboy I asked Bill to mod my Stage2 to support a turbo on my '01 MAP and after an initial plan, didn't get any further responses.

So I'm going with a Bell Eng RRFPR and an eManage Ultimate on top of my Stage 2.

From Bill when I was talking to him about it: "We changed the A/F ratio and Timing values. Now if you are running boost with some piggybacks I have found running a tuned ECU and then adding in the piggybacks works a whole lot better then trying to tune a car with a stock tune (super rich) and then try to lean it out. It just messes everything up, plus the curves are usually not smooth which ours are, once again making it easier to tune."

I'm hoping to dive into it after I get back from my work trip this week. I shouldn't have to travel again for 3wks, so I should be able to get her running in that timeframe.
 

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00-01 SOHC MAP

THIS is where the ECU rules change and get progressively more complicated. 10:1 compression is pretty much "THAT" limit for boost and pump fuel. You also have to get around the MAP sensor that hates seeing boost. 8psi is again the happy zone for the motor. Timing retard will let you get to 12psi safely.

02+--why you shouldn't do it and you're on your own from here...
:Gost:

OK I couldnt read the entire thread, me eyes got tired... so i have a Q: I am new to subies so I am surprised to read that the went from MAF to MAP when everyone else went from MAP to MAF. Sooo My 200o just has a MAP? If so, "get around" how? On my mustangs I would convert the MAP to MAF with a ECU and a few harness changes but it sounds like you have a diff idea. Please clue me in :) Also, are you all using an MSD BTM to pull timing or what?
 

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Tubaru Pickup
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Super aggressive timing. I'm going to ask for stock timing (actually, pull 2 degrees between 3-4k, pull 4 between 4-5k, and pull 6 between 5-5.8k). I'll also get my limited brought downto 5800rpm (I didn't make power past that anyway).

My original idea was to run an 8:1 and get the 10:1 disk just in case.
put it this way. i was pulling 15 degrees of timing at 22psi. and i was still at 20-24 degrees btdc at peak torque. WRX/STI guys run about 18. calling the stock na ecu aggressive is an understatement. im pulling 10 degress at 10psi while i break in NEW motor.

but it dont matter what you pull, the ecu will continue to raise timing until it detects knock, then it retards a little.
 

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2000 2.5RS/C BRP
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OK I couldnt read the entire thread, me eyes got tired... so i have a Q: I am new to subies so I am surprised to read that the went from MAF to MAP when everyone else went from MAP to MAF. Sooo My 200o just has a MAP? If so, "get around" how? On my mustangs I would convert the MAP to MAF with a ECU and a few harness changes but it sounds like you have a diff idea. Please clue me in :) Also, are you all using an MSD BTM to pull timing or what?
Well, there's a few options for the MAP cars. The hack'd way is to run a voltage clamp on the MAP sensor voltage line (to prevent a CEL) and use a RRFPR to add the requisite fuel and let what little tuning the ECU can do via the O2 sensor handle the trims.

These days though, that's considered a bit low-tech. With the large number of piggyback options available, that's the preferred way to tune a MAP street car. This will also let you properly tune the fuel.

With a piggyback, they will also control timing, so that's that problem sorted. For a voltage clamp, timing can be done with something external, like a Apex'i Super ITC, or you CAN leave it up to the ECU to pull itself back, but it's rough.

Obviously the simplest answer is a standalone, but then inspections, tuning, etc, etc.

You can also put a WRX ECU in there, that's what I did. If you want you could run a MAF like a WRX (though obviously a tune will be required because it's a totally different engine), or you can flash the WRX ECU and use speed-density, a COBB AP, there's lots of options.
 

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Well, there's a few options for the MAP cars. The hack'd way is to run a voltage clamp on the MAP sensor voltage line (to prevent a CEL) and use a RRFPR to add the requisite fuel and let what little tuning the ECU can do via the O2 sensor handle the trims.

These days though, that's considered a bit low-tech. With the large number of piggyback options available, that's the preferred way to tune a MAP street car. This will also let you properly tune the fuel.

With a piggyback, they will also control timing, so that's that problem sorted. For a voltage clamp, timing can be done with something external, like a Apex'i Super ITC, or you CAN leave it up to the ECU to pull itself back, but it's rough.

Obviously the simplest answer is a standalone, but then inspections, tuning, etc, etc.

You can also put a WRX ECU in there, that's what I did. If you want you could run a MAF like a WRX (though obviously a tune will be required because it's a totally different engine), or you can flash the WRX ECU and use speed-density, a COBB AP, there's lots of options.
Good info! soooo Moving the MAP vacuum tube/signal to the upside of the intake before the compressor doesnt sound like an option huh?

What years WRX ECU would work on the 2000? :gaga:
 

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2000 2.5RS/C BRP
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Read up on how speed-density fueling works, that should help you understand the options, but no, putting the vacuum line before the turbo would absolutely not work. That's one of the two primary fueling sensors, it needs to see accurate data.

Since it would see more vacuum at higher RPM, it would actually PULL fuel at high RPM. Really not what you want. It would see little vacuum at idle (near atmosphere pressure, WOT in NA cars' intake manifolds), so run rich, the at high rpm it would see high vacuum (low throttle in an NA manifold) and run uber lean.
 

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1993 Subaru Legacy Wagon
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I can personally atest to the awesomness of boosing these N/A blocks. I boosted my 1993 legacy wagon that has the dual port ej22E.
I have a full write up on how to do it here.
So you want to Turbo an Ej22E? | Turbo Timer
Leave a comment on the blog to let me know what you think. share this link with those that have questions on how to boost these motor's.
 
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