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Xnke

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Posts posted by Xnke

  1. I wish I had the income to support that kind of habit. Perhaps one day; in the not-so-distant future...

     

    Need to find a job as a wrench, or push my side business to the front and make it my business.

  2. Check your injectors; look for a 36V spike or so at the end of the injector pulse. it SHOULD be there...if it's not, then it's getting shunted into something else.

     

    The biggest noise issues with MS-V3.0 are INSIDE the box! As long as you are running shielded wiring for the RPM input, and your coil and plug wires are not across your sensor wiring, then the biggest noise contributors are going to be the alternator and then the PWM flyback circuits installed on the mainboard...the PWM idle circuit can also contribute.

     

    The PWM flyback circuits draw power directly from the same pin that feeds the main processor!

  3. Still looking at battey relocation, going to see about getting a PC925 battery to stash in the spare tire well. it's too small to hold a 17" wheel with the proper offset, mostly due to my smashing about with a hammer to get it straight-ish again when I repaired the rear deck of the car.

  4. How do the bearing surfaces look? Any scoring or marks in the top-side of the cam towers?

     

    Two cams failing this way, something's not right in the lube flowchart.

     

    Low spring pressure, clean fresh rockers, good wipe pattern, cam and rockers lubed with a good moly disulfide lubricant, quality oil, 2000RPM break in speed with good oil pressure in the block...All the checkmark things to break in a flat tappet cam.

     

    Gotta be a lube flow problem, I think.

  5. I am going to go out on a limb here and give you a stab at the specs...

     

    252* duration advertised, 108 lobe center, about 450 lift...

     

    A very small lobe profile...but bigger than stock.

     

    I have absolutely no proof in any direction...but you could send it to any cam grinder and have them profile the cam, or you can spend a little time with a degree wheel and a dial indicator and measure out the specifications yourself.

     

    Cal-Cams may no longer be in business, might be a different name now, could have been bought, ect. They might still be in business, too!

  6. It's the same thing, Dan, and I have matched the calibration curves a dozen time now trying to figure that out.

     

    Unburned fuel from a miss will read as lean, because the sensor compares Oxygen levels, NOT fuel levels! If it detects oxygen in the exhaust, it reads as lean, regardless of if it is a true lean (not enough fuel to combine with all the oxygen) or a miss (unreacted oxygen due to lack of combustion).

     

    I think I may simply just have a worn out sensor. I don't know. The car acts rich, driving wise, except for the little stumbles and misfires. I probably am running too much timing and too rich a mix at cruise, even the the car is getting great milage, comparatively. I normally set cruise by ear...lean it out till a drop-throttle event gives me the nicest sounding snaps and pops out the exhaust, then turn overrun fuel cut on to kill the popping.

  7. Misses occur at random, at all RPMs. I idled the car at a reported 12:1 AFR and then shut it down and pulled the plugs. Clean white, with only the slightest HINT of tan. Re-calibrated the sensor, tested the sensor with unlit butane lighter...will go full lean in clean air, and full rich with the butane spewing into it. Installed the sensor, fired the car, MS still reads out a 12:1 AFR at idle. Plugs are STILL clean white, with only a little hint of tan on some spots. If it was a carbed car, I'd richen it up just a smidgen and call it a day...they are that consistent, cylinder to cylinder. Musta got lucky on my junkyard injectors!

     

    Same alternator, same entire wiring harness..I put the S12 jumper and the MS-2 daughterboard into the car. That's it. Alternator is a GM unit, it's fine...scope shows some HF noise that is shunted with a bypass cap, very little noise on the power circuits in the car.

     

    Sitting still in the car, ignition on, but engine NOT running...MAP signal is fluttering around all over the place, TPS flicks around 0.5%, coolant temp flickers 1 degree up/down, MAT flickers up/down 1 degree.

     

    With engine running, nothing changes except that the MAP is +/- 0.8kpa of the center value, wideband flickers +/- 0.5AFR, coolant temp is nice and clean, MAT signal nice and clean, TPS has spikes of +/-1, up and down.

     

    The missing is possibly that the car is just lean. I've never seen a car that could idle at 12:1 AND have plugs that show a slight lean condition on every plug, so consistantly. I've seen where a mismatched or leaky injector could have one plug black, the others much lighter, and show a rich reading...the one cylinder just got drowned in fuel...but nothing like this.

  8. So far, it's been fine...the majority of the drivability isses with the Q-ship throttle are that it's HUGE for the engine, and 90% of people strip the non-linear throttle linkage off because "it's ugly, I want it to be clean!". Big mistake.

     

    Also, using the internal warmup is a cool trick, water runs through the TB and operates a wax-stat to hold the throttle open for warmup. It's a nice feature!

  9. They oversold you the cam. They sell based on a 1.6 rocker ratio, not the stock 1.48. They didn't mis-cut anything...they just sold you more than you bought.

     

    Interesting about the rocker arms, though...I have 72 here they reground and every one of them is perfect. I have some more I might send in in a few months, I'll have to go through and check them closer.

  10. Skirkland, you don't seem to be running any Delta products, according to your "build log" signature...you claim stock internals.

     

    My Isky cam has different base circles from lobe to lobe, and the lobe centerlines are offset all the way down the cam...might be for a good reason! The long L6 cam twists from front to back...under load, the lobe centerlines all fall into line.

     

    Just because the base circles differ, doesn't mean the cam is bad. The lobe height may differ too, depending on who measures, how they measure, and what the base circle is for that particular lobe. Some cams are set this way on purpose; for example, the Delta cam I have has a slightly different profile for the exhaust as compared to the intake...and the base circle is 0.010" smaller in order to cut the lobe on the existing core.

     

    Also, valve jobs may be equalized differently...all might have the same tip height, might match just intakes and just exhausts, too. I've run both in the past. All of this changes your lash pad thickness.

  11. Skirkland, you state Delta does poor work...I have yet to find any work they have done "poorly". I have found oversold cams, as they were sold using a 1.6 rocker ratio to advertise lift instead of the stock 1.46 ratio rockers...but poor work? Nah.

     

    280Zex, if you are still using the stock springs, you might want to measure lift again. I have that same cam, but it's not 0.480" lift... it's 0.460" or so, once you take into account valve lash and rocker ratio. It's the max lift I would use on the stock springs, though, so not a big deal.

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