I searched and couldnt come up with the information i needed, so thank you for your time and input.

i am trying to figure out what i need to boost more for my current setup.
small 14b 5psi
eagle H rods
8:8.1 pistons

there are so many options im looking at such as the portfueler,
megasquirt.i know that the walbro 255 is a must but when it comes to injector sizes and tuning im lost .
im trying to go to maybe 15 to 20psi with a bigger turbo.
please dont flame
thanks

Since your not familiar with tuning or electronics, I would suggest to stay away from the MS or PF.

If I were you, I would get yourself a SFMU, Walbro and be done. Nice and simple setup. Maybe get some 440cc injectors and be good for 14-18psi safely and call it a day.

-MIKE-

Stroked 2.2L

Captain Caveman

96 RS Turbo 11.414 @ 119.62 MSNS, Crower 2 NA cams, BW366, 10.5 comp, UDP, 60mm TB, W/A intercooler, 3.55 tranny 567.9whp 430tq
97 RS NA 13.188 @ 103.87 MSnS powered 12.5 comp, Crower 3's and 219.4whp with 175tq
98 RS DD 12.5 comp on stock ECU, LTH, Crower 2's, Koni, GC, Hypercoil, DG hats
99 OZ 5sp Stocker 15.856 @ 85.97
99 GS stocker auto 17.7@77mph!

wiki home page:http://www.2gnt.com/index.php?d=bullettdsm

Even if you don't bother to run through the math, you should read through some of the design stuff on this page:

http://www.2gnt.com/index.php?d=Fuel System

That would help with some of the concepts of getting correct fuel pressure at idle and full boost. For 5 psi, an SFU, walbro 255 HP, and S-FMU will be fine. For 15 psi, you should get larger injectors (high 3XX cc/min to low 4XX cc/min is appropriate). If you go too big, you will have trouble with running rich at low load. You can certainly run up to 15 psi on a reasonably sized turbo without any spark control. Above that and things get a little sketchier.

Corbin
'95 ESI-T

Now with more power and fewer leaks



Humble servant of the Wiki

---

2012 2500HD LML

thank you so much for your advice. One more question
i was wondering if this had anything to do with a fcd.
When in WOT the car hesitates But if i release the pedal a little the car pulls hard. Just wondering what is causing the hesitation. thanks again

If your not going MS than a FCD is a must, the eBay ones do the job.

Why did i turbo a 420a? Why is your 4g63 smoking in a ditch?

-MIKE-

Stroked 2.2L

Yeah yours any anyone else makign a simple three wire voltage clamp that can be made for 10.00.


Hesitation is more likely to be a fuel related issue. FCD issue/fuel cut will either show up as a hiccup going into boost or it may also appear as if the car is fallign on its face or shutting down. I have only see ones that will hiccup going into boost.

if your car is a 95 then you do not need an FCD. there are some 96's that wont need it either but you would have to try and see if you have any issues.

Missing link also works, but you need to keep the vent within the missing link clean. Its easy to do and you can schedule it with your oil changes and make it part of the routine.

Okay, now I'm curious. If you ECU automatically goes into closed loop when at WOT, then how do you make it go into open loop?

I CONTRIBUTED TO THE WIKI!
ah... turbo. I love the turbo, the boost, the speed, the sound.
and its all better when you do it yourself. cheaper too.

Thanks again.im going to try and mess with the voltage on my fcd to see if i can get rid of the problem. BTW is there any members around the cleveland area that can maybe take a look for me.

No thats not what corbin is saying.

The ECU goes Open loop during WOT.

During cruising the ECU is makign changes to a fuel setup he is running that is not sized properly. Instead of running very lean the ECU is making changes to compensate makign the fuel system appear to be ok.

When he goes WOT the ECU goes into Open loop and relies on the Fuel map within the ECU. Only now he is seeing a lean condition becuase he is not getting enough fuel based on the factory Map.

Terry

That is what I was getting at, Terry. If you want to know more about how the ECU adjusts fuel, check out: Description of the Stock MFI System

There is some additional information at the bottom of: Building an 8 Injector Fuel System

Corbin
'95 ESI-T

Now with more power and fewer leaks



Humble servant of the Wiki

links no worky Corbin

Erik P.
Official 2GNT thread Hijacker
Some say that he's driven over more Covenant than he's shot, and that his grenades aren't where you'd expect them to be...
All we know is, He's not The Stig... But he is The Stig's Spartan cousin!

Thank you for the links. I looked through them and cant seem to make a decision.i realized that my 12:1 fmu will be too much for higher boost pressures and isnt adjustable. I guess thats part of learning. lol but I will probably go with the fpr 440s and walbro 255. Definitly need to get a wideban instead of the narrow.

Curious what is your hp goals? Besides just around 20 psi dd. Obviously different turbos give you different numbers.

Car Status: P0140 o2 circuit number bank 1 sensor 2 Cel. Ill fix it tomorow lol.

Estimated mileage on engine: 15,xxx

i never really set a goal but maybe 300 350 with a .60trim garrett.

Okay, so basically you have to use a datalogger and some sort of piggyback system to get the correct fuel curve for the application. Sorry to be jumping in the thread but it might help someone else later.

So here's what I will be running on my final setup, let me know what you think and if I'm forgetting anything please let me know. Built bottom end, crower 4g63 valve springs, T3/T4 w/ external wastegate, 3-wire FCD, Wideband, 340-440cc injectors (not quite sure yet), EGT, vortech SFMU, Walbro 255, boost controller, and a SAFC. I want to run 12lbs around town, and around 20lbs at the track (we have friday night test and tune at VMP so that helps a bit on the tuning).

So here's my question- if I'll be running a SFMU, each disc/ring combo will give me a different fuel curve under boost. Would I need to use a datalogger (wideband) to get the fuel trim under boost and then switch out the disc/ring to achieve that proper curve? I already know I'd have to use the SAFC to adjust fuel in closed loop. But at open loop it dumps the max amount of fuel that it can, and with the SFMU and larger injectors, that would be alot of fuel. I don't want to run pig rich but I don't want to break a ring land again either.

I CONTRIBUTED TO THE WIKI!
ah... turbo. I love the turbo, the boost, the speed, the sound.
and its all better when you do it yourself. cheaper too.

If you intend to let the stock ECU control fuel, it helps to have a datalogger. That lets you see what the ECU is thinking. Whether you have an S-AFC, S-FMU, or extra injector, the ECU will still try to adjust the fuel the way it wants when in closed loop. You have more control personally when the ECU is in open loop. A wideband will let you tune open loop appropriately. I suggest you watch what the ECU is doing in closed loop at idle to help set your static fuel pressure and S-AFC (low load). Aim to keep your short term fuel trim around zero. You will choose your disk and ring combination to give you the appropriate A/F at full load (peak boost and torque). This is where the wideband comes in. Ideally, you want the S-AFC (high load) set near zero at full load. This is just to keep the ECU from advancing your ignition timing at full load (unless you want more broken ring lands). Ideally, you wouldn't even use an S-AFC because of its dangerous side affects. Ideally, you want to set the static fuel pressure and disk/ring to give you reasonable fuel trim at idle and reasonable A/F at full load. As you keep increasing the boost, this becomes less feasible. Personally, I would be scared to run 20 psi boost on a T3/T4 with such a basic fuel system (not to mention igition control). I would only dare to run 12-15 psi on a fuel system incorporating the stock ECU. I ran 9 psi on a S-FMU system, 15 psi on an extra injector system, and am playing with 15-20 psi on a stand-alone system. I am conservative, but I also haven't broken anything. You will get much more aggressive opinions as well.


Corbin
'95 ESI-T

Now with more power and fewer leaks



Humble servant of the Wiki

Wow, that was exactly what I was looking for. Dude seriously... you should write a book (even though you already have on this site). But that helped me out alot. Thanks. Hopefully, the next person looking for this info will find their way to this thread.

Another thing though, what do you think would be a good datalogger for around 12lbs? I guess the amount of boost won't really make a difference, but I want to get into the tuning aspect of boosting without the huge price tag of a shop and dyno time.

I CONTRIBUTED TO THE WIKI!
ah... turbo. I love the turbo, the boost, the speed, the sound.
and its all better when you do it yourself. cheaper too.

I can't say which is the best, but I have been very happy with the product and seller at http://www.obd-2.com/

I have been using that hardware for around a decade. It is for people who want to use a laptop. You will want the ISO hardware. Most dataloggers will read the same data. You can often use multiple software titles with a certain hardware. If you prefer to not to use a laptop, there are PDA options available from other vendors.

Corbin
'95 ESI-T

Now with more power and fewer leaks



Humble servant of the Wiki