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Thread: C950 22S issues

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  1. #1
    exocaged Guest

    Default C950 22S issues

    its the 22s model

    I just cant get the thing tuned right. Have had it on for 6 or so years and although it has been close, it has never been right.

    Cam specs: Its a Speed Pro roller camshaft. pt# CS195R

    2000-5500 rpm range
    289 intake/ 299 exhaust adv. duration,
    duration @ .050 of 212 intake and 222 exhaust,
    Valve lift of .493 intake and .510 exhaust,
    Lobe C/L is 112

    the rest:
    Full roller rockers
    AFR 185 58CC heads
    stroked to 408 with 27.5CC dished pistons for pump gas

    This is an off road play truck, I rock crawl and sometimes play hard with it. its on 46" tires with a full manual C-6 tranny with a 2200 stall B&M converter. Axles have 4:88 gears and I also have a 4 to 1 Transfer case. Gearing is fine as it rarely ever gets put in 1 to 1 or put on pavement.

    to make it run descent I have to force it to run rich according to the O2 reading. The 347 ford base map wont run it ( yes I switched it to TBI ) I have to set the idle values to 25-26 to get a smooth/usable idle. The TBI fuel pressure is 24psi. I have never been able to get it lower for some reason. The return is 3/8 and its a nice straight shot to the cell with not hard turns or kinks. The exhaust is pace setter shorty headers into a single 3" pipe.

    if anyone can help me I would greatly appreciate it.


    Thanks
    Joe

  2. #2
    Join Date
    Dec 2009
    Location
    Connecticut
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    23,510

    Default

    Quote Originally Posted by exocaged View Post
    To make it run decent, I have to force it to run rich according to the O2 reading.
    The TBI fuel pressure is 24psi. I have never been able to get it lower for some reason. Thanks Joe
    Specifically, are you having idle problems?
    Have you integrated a wideband O2 sensor (feedback to ECU)?
    What exactly happens when attempting to lower fuel pressure?
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: 385" SBF, Dart SHP 8.2 block, TFS TW 11R 205 heads, 11.8:1 comp, TFS R-Series intake, Dominator MPFI & DIS, 36-1 crank trigger/1x cam sync, 160A 3G alternator, Optima Red battery, A/C, 100HP progressive dry direct-port NOS, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/off-road X-pipe/shorty headers, S&W subframe connectors, LenTech Strip Terminator wide-ratio AOD/3000 RPM converter, FPP aluminum driveshaft, FPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & MT 245/45R17 tires.

  3. #3
    exocaged Guest

    Default

    i can make it idle just fine. I just have to force it to run rich according to the O2 reading. If I lower the value down to let the O2 do its thing, it starts surging. Even with a flat area surrounding the idle point. I have tried to adjust how fast it adjusts itself too with no good results. When I attempt to lower the pressure it just does not go down. just stays where it is, has been at 24psi since day one, no up or down at all. No i do not have the wideband O2 sensor. I feel it should work better as it is.

  4. #4
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    23,510

    Default

    Quote Originally Posted by exocaged View Post
    I can make it idle just fine. I just have to force it to run rich according to the O2 reading. If I lower the value down to let the O2 do its thing, it starts surging. Even with a flat area surrounding the idle point.
    What are your O2 Compensation Limits (%)? Seems like your target O2 voltages are fighting your Fuel Map idle values. The Fuel Map values should not be flat in the idle area. It should be arranged (tuned) to manipulate the surrounding idle RPM & kPa cells to divert the highlighted cell toward the center target idle cell. I can explain further if you'd like. Conversely, the timing map should be flat in the idle area. How much timing advance are you using in the idle area?


    I have tried to adjust how fast it adjusts itself too with no good results. When I attempt to lower the pressure it just does not go down. just stays where it is, has been at 24psi since day one, no up or down at all.
    The fuel pressure regulator should be sensitive to adjustment with a 5/32" allen wrench. I would disassemble the fuel pressure regulator and inspect for damage. Use this regulator kit to service it: http://www.holley.com/512-1.asp


    No, I do not have the wideband O2 sensor. I feel it should work better as it is.
    Your C950 EFI system will not function better with a narrowband O2 sensor.
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: 385" SBF, Dart SHP 8.2 block, TFS TW 11R 205 heads, 11.8:1 comp, TFS R-Series intake, Dominator MPFI & DIS, 36-1 crank trigger/1x cam sync, 160A 3G alternator, Optima Red battery, A/C, 100HP progressive dry direct-port NOS, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/off-road X-pipe/shorty headers, S&W subframe connectors, LenTech Strip Terminator wide-ratio AOD/3000 RPM converter, FPP aluminum driveshaft, FPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & MT 245/45R17 tires.

  5. #5
    exocaged Guest

    Default

    By better, I meant better then what it is. I have read that the wideband is better then what I have. I'll adjust the fuel map this evening to get closer to what you are saying. I tried years ago to adjust the pressure like you describe. Nothing changed the pressure and since it was new I really didn't want to mess anything up so as I counted the turns I put it back where it was.

    My O2 compensation limits are at 20%.

    My timing at idle is about 30 degrees. It get rough and erratic when I drop it much lower. Starting timing is 18 degrees. Starts fine.

    Is there a way for me to simply post the maps and other info on here?

  6. #6
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
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    Default

    Are you using a fuel pressure gauge when attempting to adjust fuel pressure?
    Change all your O2 compensation values to 25%.
    Is the engine ignition timing synchronized with the ECU timing?
    Idle timing is synced by turning distributor and higher RPM are synced with "ignition propagation delay".
    Which electronic distributor are you using? "Timing advance while cranking" is only enabled with inductive or Hall-Effect types of RPM signals.
    You can "insert images" that are hosted from another site, such as Photobucket.com.
    Last edited by Danny Cabral; 05-02-2010 at 01:54 PM.
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: 385" SBF, Dart SHP 8.2 block, TFS TW 11R 205 heads, 11.8:1 comp, TFS R-Series intake, Dominator MPFI & DIS, 36-1 crank trigger/1x cam sync, 160A 3G alternator, Optima Red battery, A/C, 100HP progressive dry direct-port NOS, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/off-road X-pipe/shorty headers, S&W subframe connectors, LenTech Strip Terminator wide-ratio AOD/3000 RPM converter, FPP aluminum driveshaft, FPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & MT 245/45R17 tires.

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