Your MAP sensor plumbing to too complicated. Simplify it. The SC cams have limited overlap. You do not need a vacumn cannister/resovoir as the vacumn pulse is smooth.

On my 3.2 w/TWM's and EFI (running big cams GE80 with lots of overlap) we run a vacumn hose from each TB to a T to the MAP sensor. Make sure the MAP sensor is turned facing down, so any condensation drains out. Condensation will ruin the MAP sensor and you will be chasing your tail....

With a N/A motor you do NOT need the vacumn adjustabe fuel pressure regulator. Set your fuel pressure and be done.

As idle is an issue, try getting it to run at 1,500 RPM, then do the NO load maps - in 500 RPM increments.

Does thhe ECU have a barometric compensator? If so, turn it off. eliminate some of the variables.

Onced you get it sorted, you will really enjoy the drivability and performance of EFI!

Others have provided some great advice here. Make 1 change at a time! Check EVERYTHING! Good luck!

If all else fails, sell the magasquirt and buy an other ECU where you have access to a tuner familiar with the ECU....

OK...a few more things to think about:

A pulse width of 1.7 to 1.8 (BTW that is in ms) is just about the minimum that the ECU can dial to get the injector to lean out. The ECU will probably not go below this value because the injectors wiil be unstable.

If the ECU is responding it is doing so at the request of the Wide Band O2 sensor.

Insure that the enrichening circuit is off, just to assist in trouble shooting.

Voltage....insure a clean > 11.5 VDC, electronic circuits don't respond well to voltages around 11 VDC or less.

If you are running a stock SC set-up, CIS pistons and cams take out the 30# injectors and install the 21# ones.

Good luck.....again

thethrill that's interesting about the way you have the vacumn lines running as I was told by several individuals the cannisters were the way to go to smooth the pulses. If anything per your setup my vacumn pulses should be perfect. I don't have a seperate MAP unit it is built onto the mother board of the MS ECU to my knowledge as a vacumn line runs to the ECU. Boxermania yes stock pistons,cams and I agree the 21 lb. sounds like what I need. Tracking number shows the smaller injectors will arive Thursday so by Saturday afternoon you guys will either hear a sonic boom of joy or the death shrill of a maniac. I'm hoping for the joy.

Hey guys ,

Feels almost like home here ,
I'm the MS guy currently helping rfuerst911sc
with his MS Install .

I got invited over to check out this thread to see what's been goin' on .

Looks like lots of good help , and I've already been reminded
about a potential problem that I overlooked , and that's
balancing the ITBs , thanks .

Generally , I try to talk people out of running ITBs ,
just because they are such a pain to get just right and keep right .

From the phone calls we've had , I was almost running out of answers ,
but knew it had to be a basic set-up problem ,
sometimes it's hard to remember how it was when I was
just starting to learn , so I sometimes make assumptions
that the basic building blocks are known and good ,
obviously not the case .

I wouldn't be surprised to find that these injectors are
even larger than 30lbs/hr , and therefore way out of control .
Even with 30% reduced fuel pressure and a VE Table that should be
very lean because of changing to a vacuum compensated regulator , it's still way rich .
This is not MegaSquirts fault , it's just a computer ,
garbage in (wrong injector flow rate) equals = garbage out .
We shall see very soon , stay tuned . ;)

BTW , NO carburetor will out perform a properly designed
and set-up fuel injection system ,
ever seen a F-1 car with carbs ?
Not even motorcycles or outboard motors come with carbs anymore .

The trick is you need to understand WHY something works
or doesn't work .

Keep up the good work guys :)

...................Jim

I'm impressed with JIM....His very 1st post and he's here to help....I don't have EFI, but am here to learn.......

Jim,
It's good to see you here... see you help folks on the MS forum often :)

rfuerst911sc, as many suggested, you can turned off many things in MS to start - baro correction, accel enrichment, EGO correction, ... Heck, if you want, you can even change to use Alpha-N for a test that will completely use TPS/RPM to control injectors as Mike pointed out earlier.

This way, you can narrow down if a) MS is controlling PW correctly, b) if it is & your car still runs pig rich, then it can't be MS.

Good luck...

I want to thanks Jim-MS-Guru for being patient with me and walking me thru this, without his help I think the revolver would have been pulled out of the drawer!!! And of course all the Pelicans that have subscribed and offered suggestions. I'm feeling much better about a forward path to get my 911 running correctly. Great forum great people.

Jim was very helpful to me on the MS forum to go over my system. He had some great tips for getting started.

I have a feeling that rfuerst will take the 2-ish hour drive over to Crystal River to show just what it can do... And of course, to say thanks. I know I would. besides, there are somenice backroads between the two locales...

I strongly suggest to USE vacuum adjustable pressure regulator for various reasons.

First of all: injectors are created for specific pressure delta over them. Most of the time it's 3 bar. If vaccum compensation is deleted, pressure delta will jump from whatever FPR is adjusted to (usually 3 bar) to 3.8 bar while off-throttle, resulting in higher amount of fuel being injected, with different spray pattern (due to higher pressure than pintle has been designed for).

Of course, these things can be corrected in VE maps but there is really no point of doing it. Pop the hood in virtually any OEM N/A car and you will find vacuum-corrected, non-adjustable FPR (with 3 bar system pressure in 95% of cases).

With other words: adjustable FPR is a wide-a$$ed and ham-fisted way of adjusting fueling which can and should be done in software instead. Fiddling with fuel pressure in non-standard way will just introduce yet another string of unknown parameters. Nice things with using 3-bar constant pressure delta FPR are:

1. Always same pressure over injector = consistent spray pattern and consistent fuel amounts. With other words, 50% longer PWD will most likely result in 50% more fuel = good thing

2. Repetability = Map can be transfered from one to other car and easily scaled to adjust for bigger/smaller injectors without having to figure out how many turns of FPR-screw were done by the guy who made the map in his own car.

All in all, I believe it's worth to yell this:

DO NOT USE ADJUSTABLE FPR's, USE STANDARD VACUUM-CORRECTED FPR's WITH SYSTEM PRESSURE THAT YOUR INJECTORS ARE SPECIFIED FOR. (this is even more valid for turbocharged cars as pressure deltas are bigger)

While it's possible to circumvent weird non-linear fueling issues that stem from yet another tweakable-thing-that-doesn't-do-any-good (TM) trough painstaking mapping, it's much easier to control fueling in only one place where it should belong: ECU fuel maps.

FYI

The saturated injectors (most of all applications) measure betweem 12 to 16 ohms resistance.

The Bosch 19# the top is yellow, the 24# the top is blue, the 30# the top is red or brown....if my mind doesn't fail me.

If you'd like send me a datalog of the engine idling and some throttle punches, and I can have a quick look to see if anything is out of the ordinary.

Also send me your configuration file (.MSQ) and I can have a look over.

Ever get the feeling things just weren't meant to be? Apparently the sender of the smaller injectors had my address off by one number. Unfortunatly the address does not exist in my community and it was delivered to the mystery address today per FED EX tracking number. I called FED EX one hour after it was supposedly delivered and they will try to find it. Don't worry guys my wife has hidden all sharp objects!!! Tbitz if I ever get the car running I'll send the files. Thanks for the offer.

jpnovak the injector part numbers I received yesterday in the mail are 0280150455 and are supposed to be 21 lb. per hour and they came out of a Boxster. The injectors I am removing from the car are 0280150945. I'm curious what your website says those are in size as I was told they are 30 lb. per hour. I should be firing her up in the next 2 hours or so.

rfuers

Checking the injector numbers gives me:

the 455 - 21 lbs injectors, 12 ohms

the 495 - 30 lbs injectors, 13.8 ohms red/brown top ("Ford Motorsport Inj")

I'm eager to know that your engine is running right.

That 2nd number is not 495 it is 945. Does that change what they are? They are a reddish brown top injector. I'm turning the key in about an hour I'm trying to get a hold of Jim to clarify a few settings.

Directly from a Bosch catalogue:

0280150455: 12 ohm, 172,4 g/min (n-heptan @ 3 bar) = 22,7 lb/hr
0280150945: 14,4 ohm 229,8 g/min (n-heptan @ 3 bar) = 30lb/hr

I can say it directly, 945 injectors are way too big for a pedestrian 3.0 SC engine.

I did a calculation of big injectors a 204hp 3.0 SS engine would need @ 6000 RPM. Assuming 80% duty ratio and AFR of 12.7:1, you would use 773 g/min which is (if we convert it to mongo imperial system that even Brittons quit using) 17lb/hr.

So 22,7lb/hr Boxter injectors will be just fine.

Well I just fired her up and it is a little better. Once warmed up my idle AFR is about 11:1 vs. 10.1:1 that it was before. Idle pulse width is around 1.8 to 1.9. I tried to lean it out useing megatune by adjusting the VE table but it doesn't respond like I would think it would. When I lean it out in the VE table shouldn't I see the AFR rise towards lets say 12;1? She is still very rich because my clothes reak from raw fuel. Occasionally at idle I get a brief TPS enrichment what would trigger that? When that happens idle speed drops but then recovers. I may have reached the end of my tuning ability as I don't know what to do now.Anyone want to purchase a slightly used EFI setup?

send the info to Tony at BITZ racing he can help you out

Turn off all accel enrichment while you are tuning idle.

Can you take a screen shot of your VE table and various other screens so we can see your settings?

rfuerst911sc, I agree with Ben - trying posting it here or at the MS forum too so some of us can try to help.
A couple of thoughts & questions in the mean time -
a) What kind of O2 sensor/system are you using (sorry if I missed that earlier)?
b) If you are getting TPS enrichment @ idle - then you need to set the threshold higher to start.
c) Forget AFR - how does she run right now? When you step on it, does it rev smoothly? Does it sound like you have appropriate ignition advance? What is your idle timing?