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Need thoughts/opinions on my 16g setup.

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GofaST4life

15+ Year Contributor
2,898
132
Oct 21, 2007
Medina 44256, Ohio
Here's the scoop.

Induction/Exhaust:
16g Turbo - Minimal side to side, marginal in and out, shaft play.
Stock SMIC w/ stock piping.
Stock turbo-back exhaust.
Running stock boost. Have a vacuum line from waste gate to the J-Pipe.
Vacuum @ idle = 19/20
Vacuum @ decel = 22/23
So far i've only seen the boost gauge read maybe 8psi.
Mitsubishi Metal BOV upgrade.

Fuel:
560 injectors
Rewired wally
Stock FPR is not hooked up.

Head/Engine:
Stock Rebuild - Cleaned and honed (not sure how many miles are on it)
Head has upgraded lifters and valves
New timing belt + Accessories.

The engine runs VERY smooth, idles perfect, doesn't leak anything, and i'm getting almost 30 mpg's highway.

Im looking for some input on where to start with my diagnosis.

I don't want to throw money at a FMIC setup or an exhaust without making sure she is running good, etc. Maintenance first!
 
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Your turbo probably has blown seals hence the blue smoke. A compression test would also deem if there is anything wrong with the motor.

16g's are not meant to run 8lbs, stop ####y-footing around, get a MBC and turn it up to 20 with a tune and you'll see it move. (BTW untuned at 8psi would make it run the way you are describing because of the 560's)

Also, I highly doubt you are getting 30mpgs with that fuel setup without a tune.
 
Your turbo probably has blown seals hence the blue smoke. A compression test would also deem if there is anything wrong with the motor.

16g's are not meant to run 8lbs, stop ####y-footing around, get a MBC and turn it up to 20 with a tune and you'll see it move. (BTW untuned at 8psi would make it run the way you are describing because of the 560's)

Also, I highly doubt you are getting 30mpgs with that fuel setup without a tune.

I'm going to do a compression test ASAP.

I'm not trying to run 8lbs, but that's all the turbo will make, granted I haven't REALLY pushed it, as i'm worried about creating more problems or blowing something up. I have an MBC, but whats the point in turning the boost up if the turbo is bad or something else is wrong.

It may sound wrong, but on my last trip I used a 1/4 tank, and went maybe 120 miles. So...
 
Its running rich due to your injectors. Only reason you highway mileage is good is because you cruise in closed loop and the o2 sensor automatically adjust to stay around 14.7 regardless of injector size. Thats probably why your fuel pressure regulator is not hooked up to a vacuum, previous owner must of done that to try and compensate for the bigger injectors. Bad idea. Either get a tuning device of some sort, or switch back to the stock 450cc injectors.
 
Its running rich due to your injectors. Only reason you highway mileage is good is because you cruise in closed loop and the o2 sensor automatically adjust to stay around 14.7 regardless of injector size. Thats probably why your fuel pressure regulator is not hooked up to a vacuum, previous owner must of done that to try and compensate for the bigger injectors. Bad idea. Either get a tuning device of some sort, or switch back to the stock 450cc injectors.

If I had the stock 450's I would.

I'm assuming from your post, I should hook the stock FPR back up. Correct? Or should I go ahead now and get an after market?


If I picked up a SAFC and Wideband, would I be able to tune the car "enough" to run it safely and to make better power/boost?

I do have a data logger on its way to me. So hopefully I will be able to get that hooked up and see whats going on.
 
Ive come up with a game plan to help fix my problems.

Going to return the car to stock-ish setting.


Found some Blue Top 450cc injectors.
Going to get a good condition 14b turbo.

Removing the 560's and the 16g until further notice.


Does this sound like a solid plan? Should I be moving in another direction?
 
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I wouldnt necessarily yank the 16g off of it just yet. You might be seeing smoke from your injectors being 20% larger than stock with nothing to compensate for them. This alone will make your car run like poop.

throw in the 450's first and see how it runs, then decide if you want to take the 16g off. I am currently running a MHI Evo316g on stock injecors and a wally 255, and am still running rich at WOT (low 10' afr). I can probably pull a few more percent out with the SAFC and still be plenty rich.

So, the stock injectors are fully capable of running a 16g at a moderate boost level. Just keep an eye on the AFR's and you will be fine.

So my solution to your problem, 450s, and a wideband. My evo3 felt blahhh at wastegate pressure too, but once it hits ehh 12ish psi, it hits pretty hard and takes off (for what it is).
 
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^Agreed 100%.

Also, be sure to reconnect the FPR reference line. The purpose of the FPR is to maintain a constant difference between the rail fuel pressure and the air pressure in the intake manifold. If you unhook it, the FPR will run 43.5psi (2G turbo base FP) fuel pressure all the time, whether you're under vacuum or under boost. If you're getting 8psi of boost, the injectors are now flowing like you're feeding them 35.5psi, which turns your 560's into 506's, -also they will flow like 626's under 22 in/hg vacuum.

Obviously, fuel pressure affects the flow rate of the injectors. When it is hooked up properly; under vacuum the FPR lowers fuel pressure, under boost it increases fuel pressure on a 1:1 ratio with boost in order to maintain a constant flow rate out of the injector, -thereby allowing the ECU to control the amount of fuel injected solely by commanding a precise injector pulsewidth. There's no way you can have 560cc/min injectors, no compensation for them, no pressure regulation and still have the fuel trims doing what they should. You're pretty lucky you haven't damaged anything yet, let alone how you got 30mpg.

Fix the FPR and get that SAFC, wideband and datalogger up and running as soon as possible.
 
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THANK YOU guys for chiming in!

Ok, so my action items:

1. Hook Stock FPR back up. This has been done.
2. Purchase & Install stock 450cc injectors
3. Purchase & Install Wideband
4. Purchase & Install SAFC

One major question:

Do I need to have my ECU messed with in order to run a Wideband and/or SAFC?

There's no way you can have 560cc/min injectors, no compensation for them, no pressure regulation and still have the fuel trims doing what they should. You're pretty lucky you haven't damaged anything yet, let alone how you got 30mpg.

I know exactly what you mean. Crazy thing is, the car has been running GREAT. Idles perfect and everything. Even my gas mileage around town has been very very good. Better than my last 5 DSMs at least. Which make me wonder, haha.
 
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Do I need to have my ECU messed with in order to run a Wideband and/or SAFC?

Loaded question. The ECU does not require modification. The SAFC however, will have to have it's wiring spliced into the stock ECU wiring. Since the SAFC is a piggyback, it tunes by altering the MAF sensor outputs to the ECU, which means the airflow/MAS hertz value you see when you datalog will not be actual.

Depending on what the logger supports, the wideband can be run either independently and logged on an auxiliary channel, or if you prefer, you can replace the front NBO2 and use the WB's integrated NB simulation -but that won't tell you how much you're rich or lean. Also, some loggers (like ECMLink's) allow you to reassign it to input to the ECU directly through another sensor's pin assignment.
 
Loaded question. The ECU does not require modification. The SAFC however, will have to have it's wiring spliced into the stock ECU wiring. Since the SAFC is a piggyback, it tunes by altering the MAF sensor outputs to the ECU, which means the airflow/MAS hertz value you see when you datalog will not be actual.

Depending on what the logger supports, the wideband can be run either independently and logged on an auxiliary channel, or if you prefer, you can replace the front NBO2 and use the WB's integrated NB simulation -but that won't tell you how much you're rich or lean. Also, some loggers (like ECMLink's) allow you to reassign it to input to the ECU directly through another sensor's pin assignment.

Got ya. So just so I understand this correctly.

My SAFC would be spliced into the ECU harness. So some simple wiring would be needed. But I would NOT have to have my ECU chipped or socketed, correct? I guess that was more of my question.

Also, since the logger I hope to be using is only a data logger, nothing like ECMlick or DSMlink, can a wide band be installed to show me my AFR's, if I do not have a device to log with? Basically, could someone take a completely stock DSM and install a wide band to read AFRs? (i think yes)

Going to be getting some Blue Top 450's very soon. As soon as I get them, they will be installed.
 
Any suggestions on a wide band and/or SAFC to purchase/install?


BTW, I very much appreciate the guidance and assistance. This site and community never fails to help out. Thank you.
 
Without running link or some way to simulate the front o2 you need to add a bung or run it in the rear o2 position(it'll throw a cel but run fine)

Actually the aem uego has narrow band simulation built in with the turn of a dial, so he could run it in the front o2. I know it works because I had mine setup like that until I got link and started simulating through there.
 
So that first link I posted would be okay to get and I wouldn't have to weld in a bung or remove my rear O2.
 
Haven't had time or a non rainy day to get the 450s installed.

ON a side note, the car has been getting crazy good mileage around town, so im not sure whats really going on here.

Granted, i'm really never in boost. The 16g on the car seems to have a hard time spooling up before 3000rpm's, and even then im only seeing maybe 5 to 7 psi. for a short burst.
 
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I notice you have a rewired walbro 255, that may have overrun your stock FPR too.
 
Aeromotive is usually the choice recommended.

Before you go spending a bunch of money on an SAFC, which you'll likely want to get rid of eventually for a comprehensive tuning solution (the SAFC is a bandaid, not a solution), what year is that car? If it is a 2gb impersonator, then disregard this... But if it is a 98 or 99 and has a black box ECU in it, forget the SAFC and get ECU Flash, Evoscan, and Ceddymods... Then you can just reprogram the ECU to run whatever size injector you want to correctly. Even if you don't have a black box ECU now, an SAFC is going to cost you close to what you'd spend to get a flash ECU setup anyhow. I use a 98 GST ECU in my 95 and just flash whatever modifications I need to the ECU and it works as it should, and it is MUCH better than my old SAFC was by a long shot. If you go this route though, I would recommend getting an Evo VIII ECU and Tephra Mods instead. The Evo ECU has a lot more support than the flash DSM ECU's.
 
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