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Everything posted by Chickenman

  1. Low compression!!!

    10 year old plug wires are not new. Especially carbon core wires. Wires can deteriorate just sitting. Ozone can crack and split boots. Then you can get arc over to engine. Corona discharge around plugs is also a problem with old leads. Plug leads should be checked with an Ohm meter. Just looking at them is not good enough. Pull your plugs and take some High Resolution close up pictures. use a good digital camera or a good Smart Phone camera. We need sharp clear pictures. Turn the flash off. It will skew the plug coloring. Try to get some good side on shots of the center ceramic and the full view of the side electrode. A Top angled view is best. How old are the plugs? Plug reading will tell you a lot about the engine running condition. I noticed the smoke. Sounds like you have an exhaust leak. Wouldn't surprise me if you have a leak at the exhaust manifold. Check for loose or broken exhaust studs. Also any evidence of soot around exhaust manifold or cracks in exhaust manifold. Engine sounds noisy. probably needs a valve adjustment . If that has recently been done, then it could indicate that rocker arms are worn. They will wear with a horizontal line across the wiping face. If you can feel the line with a finger nail dragged across the surface, then the rocker needs re-surfacing or replacement. No amount of adjustment will get rid of rocker noise when they get that worn. But, I don't think that's your issue though. It's really hard to tell how an engine runs in a video. But in general, I think your car just needs a bit of a sharp Tuneup. It doesn't sound all that bad. But loaded up on the road could be a different matter. Carb adjustment, carb balancing can work wonders on these engines. Also the distributor advance mechanism tends to seize up on these motors. Both mechanical and vacuum sides must be checked for free operation. The rotor should fit snug on the shaft. I've seen after market rotors that fit very loosely on the shaft. That's no good. You should be able to take the rotor and twist it about 20 degrees in the direction of rotation. Then quickly release it and it should " Snap " back to resting position. If it is hard to rotate or slowly returns or doesn't return all the way, time to take the dizzy apart and service it. You will have to clean and lubricate the mechanical Cam and governor weight system. Use a Vacuum pump to check Vacuum advance. Get the FSM specs and test it. Movement should be smooth. Hold vacuum and freely return when the vacuum release. The breaker plates have tiny ball bearing in them, and these ball bearing often rust or even fall out. Jason Grey's distributor page has a wealth of info: http://newprotest.org/projects/510/jasonGrayDistributor.pl Here are specs for popular Z car dizzys in Excel format: Distributor advance curves.xls
  2. Low compression!!!

    The instructions for your plug gapper are are wrong. That's way too much of a gap. Period... end of story. Been using these things for over 40 years. That is a FRACKING strong spark!!! Both appearance and noise show that secondary side is working damned good. It only appears intermittent because the spark has found an easier path to follow than through the HUGE gap of your spark tester combined with the gap from the plug. You are using the Tool wrong, and may have damaged other components ( such as inside of Dizzy cap and rotor ) by running such a huge gap when testing. BTW, have you checked your HT leads with an Ohm meter yet? . Those leads look like old style OEM carbon core. They deteriorate with age. Upgrade to some good quality spiral core wires such as NGK. Edit: Here is a video from Mac Tool showing the proper way to use a spark tester and the proper gap settings. Note that he mentions that the printed numbers on the tool basically mean dick squat. This is the same Mac Tools spark Tester that I use. Also note that the maximum gap setting that the Technician opens it up to is about one third of what is shown in your video. https://www.youtube.com/watch?v=YNIIllZRNRw
  3. Megasquirt Relay Board with Bosch 044 fuse blowing

    Holy Hanna... I finally found some specs on Fram G3 filters. They are rated at 5 Microns. That's far too small to be used as a pre-filter for ANY EFI pump. Let alone a high volume pump such as a Bosch 044. Get rid of the G3 and put in a recommended Aeromotive pr pump filter which are 100 Microns in size. Fine filters should only be installed post pump. Thanks Atlantic Z for perpetuating this incorrect information. I was wondering about this ever since I installed a Fram G3 before my Airtex 8312 EFI pump based on the Atlantic Z article.. It's a Ceramic turbine pump, so it does need a pre-filter according to Airtex. In Tank pumps have a sock to catch the coarse stuff, but an inline pump doesn't. Would have been nice if Airtex had recommended a proper inline Pre-filter... but they don't. My pump had been getting growly and noisy during hot weather. Worse when fuel tank was below 1/2. Mkaes sense now as this is a Textbook case of a restrictive fuel filter being installed before the pump ( Fram G3 ) . G3 is going bye bye and I'm ordering a proper Aeromotive 100 Micron SS filter from Summit ASAP!!!
  4. FPR and Fuel Pressure Help

    Deleted. Wrong thread.
  5. Megasquirt Relay Board with Bosch 044 fuse blowing

    Further reading on Fuel Pump Cavitation and starvation caused by restrictive Pre-Pump filters. http://aeromotiveinc.com/wp-content/uploads/2014/12/TB_101_InletFilter02.pdf http://aeromotiveinc.com/wp-content/uploads/2014/12/TB_802_Tanks_Sumps_Stealth_02.pdf Aeromotive has some excellent Tech Articles. Well worth reading them all. https://www.aeromotiveinc.com/tech-help/tech-bulletins/
  6. FPR and Fuel Pressure Help

    Aeromotive 13129 EFI regulator will also work just fine, is a quality part and has a reasonable price. https://www.summitracing.com/int/parts/aei-13129/overview/ The stock FPR simply cannot handle the Bypass return volume that a High Volume pump provides at idle and low RPM's. Internal orifice is simply too small. At idle, with bigger injectors and a high volume pump you can be Bypassing 80 percent of the fuel volume back to the Tank. FPR has to be designed internally to handle this amount of flow and maintain a steady pressure. Many new cars use a PWM Fuel pump that reduces flow at low loads to aid in maintaining a properly regulated rail pressure.
  7. Which vac hose to tap for boost gauge? (with pics)

    Red or yellow Vacuum cap should be fine. Do I get a prize??
  8. Rear Bumper Patch?

    I've occasionally seen Fiberglass replica rear valances on E-Bay.
  9. Trigger Wheel VR Sensor Question

    To answer your first question. Yes, bring #1 to TDC. Then rotate the Trigger wheel backwards so that the Missing tooth passes the Vr sensor at least 60 to 70 Degrees ( 70 preferred ) before TDC. That will be your course setting. Then make the " Fine " setting by adjusting #1 Tooth angle. I take it your trigger wheel is held in place by a Center bolt and can be infinitely adjusted?
  10. Trigger Wheel VR Sensor Question

    The sensor has to be mounted so that the missing tooth passes the sensor 60 to 70 Degrees MINIMUM before the piston reaches TDC. That is because a programmable ignition system does not actually ADVANCE the ignition timing. With an old style points system, the breaker plate physically moves the points ( or VR Reluctor ) vian Mechanical weights and Cams and the Vacuum pot. That physically does move the sensor location and ADVANCES the ignition. With a programmable system, the sensor location is fixed. So you have to start of with a figure that is higher than your maximum advance ( which can be up to 45 to 50 degrees BTDC in light load cruise mode ) and add a margin for the CPU to make calculations. So the ECU has to know when the piston is APPROACHING TDC ( of #1 cylinder ) Lets say you want a timing figure of 10 BTDC. Sensor is positioned so that missing Tooth pases sensor at 70 BTDC. 70 - 60 = 10 BTDC. Now lets say you want 40 degrees of advance at cruise. 70 - 30 = 40 BTDC. The ECU just delays or RETARDS the timing less. Always remember that the CPU needs some time to make these calculations. If you place the VR sensor too close to TDC, so that the missing Tooth only passes the sensor at say 45 degrees BTDC, the ECU may not have time to do all the calculations and subtract the necessary timing amount. Then timing fluctuates. Then you have to Sync the ECU Timing to the engine Timing with a Timing light. Usually to a Locked Timing of 10 BTDC. This is done in the Software. by adjusting #1 Tooth angle or by using the Trigger Wizard., depending on type of Ignition system used. All this is is a fine Tuning. You are adjusting the basic idle with software, instead of twisting the dizzy as with an old style Mechanical system. That's the only difference. Once you wrap your head around that it becomes easy peasy. What version of MS do you have. MS2 and MS3 are pretty simple. MS1 can be a bit tricky as it's ancient.
  11. Low compression!!!

    You may want to check the dizzy cap and rotor now. By having such a large gap on the testing tool, combined with the plug gap... you could have created an Arc Over and carbon traces inside the dizzy cap or rotor. Get a magnifying glass and look for Carbon Traces jumping form terminal to terminal or even to the base of the dizzy cap. They will look like hairline cracks or a line dean with a sharp pencil. Check the rotor as well. And also between the Coil center tower and the two primary terminals. Arc over and carbon traces can form there as well. Bottom line. You probably didn't have an INTERMITTANT spark. You had a spark that found a path of less resistance... and it went there instead of through the spark tester.
  12. Low compression!!!

    In the video... I think you simply have your spark gapping tool adjusted too far out I use these things all the time, and that is a huge gap. What spark leads are you running? If carbon core you could have a lead that has deteriorated and has higher resistance. Carbon core wires are 1960's and 1970's technology. They have no place on a High Performance car these days. Never use solid core copper wire. Will cause a lot of electrical interference. NGK makes an excellent spiral core HT set for our cars for a very reasonable price ( Typically $19.95 online ) . Part number is NE61 ( SKU) or NGK8105 ( Item number ) . Available at any decent Auto Supply shop. MSD and Magnacore also make a very good spiral core wire. But a bt more expensive. Isee you have the gapping tool hooked in series with your spark plug, condition of plug also comes into play. And added to that you have the resistance of the plug gap ADDED to the resistance of the overly large testing gap. This is improper use of the Tool. Normally I test spark output with a gapping tool by connecting the ground lead directly to a good engine ground, not to the spark plug That gives you a better indication of the True spark condition. You could also have a carbon trace inside the dizzy cap. Or the spark could actually be jumping to an adjacent plug terminal. Electricity always takes the path of least resistance. Air is a very good insulator. A Carbon trace less so. Coils don't go intermittent per cylinder. You have a good sharp spark. It is Blue and you can hear it snap. That's all good signs of a healthy coil and module. Cut that spark tester gap down by at least half and connect it to an engine ground.
  13. Turbo Dizzy (82/82)

    Rock Auto has A1 Cardone remanufactured Turbo dizzies for $182 out right. You will need a Cap and Rotor . I would recommend the Beck/Arnley brand. usually OEM Japanese parts for Nissan. https://www.rockauto.com/en/catalog/nissan,1983,280zx,2.8l+l6+turbocharged,1209406,ignition,distributor,7108 I would recommend checking all the clearances on the Dizzy. They often install a later Maxima pr Pathfinder CAS, and it has a couple of plastic " Nibs " on the bottom that do not allow the CAS to sit square. Mine was rubbing on the Trigger disc. A few minutes of " Blue Printing " and all was good. Also, sometimes both the dizzy body and the CAS are threded for mounting screws. It's a difference in how the later CAS units are mounted. If you find this is the case. Remove the mounting screws and CAS . Drill out the three threaded holes in the dizzy body so that the mounting screws can be installed from the bottom and thread into the CAS. It's self explanatory when you see it. And you will want to get the custom 54mm L28ET 12 + 1 Trigger wheel from DiyAutoTuning.
  14. A correctly sized ( and low pressure loss ) intercooler will dramatically reduce charge temps which will also reduce the knock threshold.. It will also reduce the boost necessary to produce the same horsepower. Cooler air is denser. Same HP with Less boost = better efficiency = lower cylinder pressures = less chance of detonation. A Win/Win situation. The ability of a Modern ECU ( or standalone ) to precisely control the AFR and Timing at any RPM and Load allows you to maximize the Torque and HP potential of the engine. It's very hard to improve modern EFI efficiency because of the feedback controls. Modern Dual WB Knock sensors really allow the manufacturers to push the efficiency and power envelopes. Also, car manufacturers have to make things conservative in case low Octane fuel is used by mistake. Race cars don't have that issue. The ZXT did have a factory Knock sensor... but it was a dinosaur compared to what is available today. You can also make Timing digressive at Peak Torque with programmable ECU's. Ramp timing up aggressively at low RPM's to generate maximum Torque, then back off a couple of degrees at Peak Torque ( Peak Torque is usually where detonation will occur ) then ramp it up again ( if necessary ) after Peak Torque. Cylinder heads that are prone to detonation ( N42/N47 for example ) respond well to this Timing strategy. You can also use some extra fuel to control detonation. Kind of a " Band'Aid " fix... but it will work. This should all be done on a Load Cell dyno of course. You can also do individual fuel and timing trims with most stand alone ECU's. #5 and #6 are known to run a bit hot on the L-6. So you can pull a small amount of timing from those cylinders. Or add a bit of fuel. Run multiple O2 sensors ( or EGT probes ) and you can dial in the ideal AFR for each cylinder.. Most Intake manifolds, especially stock manifold, never have equal air distribution from cylinder to cylinder.
  15. Ms3x install

    Yep... with an IAC the TB should just be cracked open. Just enough to prevent the butterfly from being fully closed and digging into the throttle body bore. With a large Camshaft, you may have to crack the butterfly a bit more, as the IAC can run out of available opening range.
  16. As long as you can get decent fuel ( 93 to 94 Octane ) , 8.6 CR is not too high IMHO. Done all the time. Race fuel would be a piece of cake Nissan went really conservative on the L28ET CR, because of no intercooler and archaic ECU controls. You can push the envelope much further with some upgrades and a decent Standalone ECU. manufacturers in the 80's through 90's were very, very conservative on most Turbo motors. Now you have EcoBost 2.3L 4 bangers pumping out 350HP... stock!! ( Focus RS ) Add a couple of VW Bosch WB Knock sensors to the block would be a smart idea on a race engine. Not too hard to do. I'm sure Tony D knows how.
  17. Ms3x install

    Here's some reading to make your Brain hurt. Written for MS2, but should apply to MS3 as well: http://www.megamanual.com/ms2/IAC.htm
  18. Ms3x install

    Good explanation of various types of IAC valves. http://ricksfreeautorepairadvice.com/how-does-an-idle-air-control-valve-work/ https://www.youtube.com/watch?v=oRo5nn9ux1M
  19. Ms3x install

    With an IAC enabled you have to physically adjust the TB butterfly more closed than if you run without an IAC. The Jeep IAC is a Stepper motor design and will always be open a certain amount. If it does not receive an ECU command it will default to the last commanded stepper position.
  20. Megasquirt Relay Board with Bosch 044 fuse blowing

    That is a possibility. Relay could be overheating on Relay Board. May have Thermal protection and relay is opening. Or some other intermittent electrical disruption. Or Bosch pump is cavitating badly and it takes a while to cool it down. Pump cavitation can do nasty things to a pump in short order. Fortunately the Bosch 044 is a roller vane design, which are much more robust than a Ceramic Turbine design.
  21. Megasquirt Relay Board with Bosch 044 fuse blowing

    Quote from Aeromotive on this exact problem. Could definately be Pump cavitation. I would definitely be looking at replacing that G3 and checking hose sizes. Further info on Pre-Filter restrictions. Read this: http://aeromotiveinc.com/wp-content/uploads/2014/12/TB_101_InletFilter02.pdf
  22. Megasquirt Relay Board with Bosch 044 fuse blowing

    Sorry... but I disagree with that. The feed pump absolutely MUST keep up with the main pump under all conditions and keep the main pump submerged in the Surge tank. You run the Ffel level in the surge pump too low and the Bosch pump will cavitate and you can kiss it good bye in a hurry. But likely you will have melted a piston by then. Feed pump does not have to be high pressure. But it must be high volume. Think of a Surge tank as a float bowl. Yes, there is some reserve, but with a GT3076 and 550cc injectors you can suck a Surge tank down pretty fast. Also depends on mounting locations of pumps etc. Pictures will definitely help. G3 Fram filter is definitely a restriction on a motor of this potential. I've run into problems with a G3 pre-filter. on a hot day on my NA motor. Switching to a Aeromotive 100 Micron filter. BTW, have a look at the 280Z stock fuel line hose sizing to and from the Fuel pump. Inlet is 11mm ID ( 7/16" ) . Outlet from pump is 9mm ( 3/8" ) That should tell you something. The feed from the fuel tank to the scavenge ( or main pump ) pump and the feed from the scavenge pump should always be larger than the outlet size from the Main Pump. If Main pump is AN-6... inlet hose should be AN-8.

    The P90 head with Flat Top pistons would have been ideal. The P90 with dished pistons is the stock The P90 head with dished pistons still has an advantage over the N42 head. The combustion shape of the P90 has a better quench area. Quench area creates turbulence in the mixture and helps prevent detonation. That is critical on a Turbo motor. When you add a thicker head gasket, you reduce quench... so you can actually end up with an engine being more detonation by reducing the compression ratio that way. Especially if you have an engine with a head design that is prone to detonation... like the N42 and N47 are. Not saying that you can't make an N42/N47 combo work... but it will be less than optimal. And for crappy California 91 Octane fuel, I would definitely run H20/Meth injection as a fail safe with an N42 head. That's just my personal opinion mind you. Either way with a good intercooler and proper engine management you can run a higher compression ratio than what Nissan did back in the day. Programmable ignition timing and programmable fuel curves will go a long way on controlling detonation. BTW, I have a NA F54 Flat top with N47 heads and 10.3 to 1 CR. I have to be careful with ignition timing on that with 91 Octane. Stock(ish ) distributor at this point.

    On injectors, I would recommend going with 550's. This will give you room for expansion. At some point you will be bitten by the Boost bug and are going to run out of injector with the 440's. The 550's are not crazy big and will idle nicely with a standalone ECU controlling things. Using the following calculator, you will see that 360 Crank HP ( 300 WHP using 20% loss ) with a BSFC of .60 ( Typical Turbo value ) and 80% duty cycle ( what you should be aiming for ) requires 476 cc/min Injectors. So your 440's may already be too small for your goals. Better to be a bit too big with injectors than too small. https://www.rceng.com/technical.aspx

    Sorry, had your build mixed up with Zeiss 150. You would be better off with a P90 head and the N42 block IMHO. Does your N42 block have dished pistons or Flat Tops? That makes a big difference to the CR. CR between 8.0 to 8.5 will be fine with a P90 head. The N42 head is too prone to detonation, unless your weld up the combustion chamber. And that's a big job. The the N42 is more of a NA head. The P90 is much better for a Turbo motor. Better quench than N42/N47 as well. BTW, adding a thicker head gasket actually makes quench worse, and can increase detonation. So you might want to re-think that. My recommendation is to build two short blocks. One with a Mule engine. Stock short block with dished pistons. Build it decent., but don't put a ton of money into it, Basically just freshen up a good used short block. This is your sacrificial Lamb for when things go Chernobyl. And they will... at some point. Melt down the cheap motor while you are learning how to Tune a Turbo. Once you have the Tune and Boost levels sorted... then put in the Big $$$ short block. Local Road Racer made 400 hp on a stock short block with Cast pistons. T3/T4 at 15 lbs boost. Engine lasted 3 seasons of Road Racing till he broke a Stock Piston ( Ring lands ) . He was expecting half a season. He actually started cranking up the boost higher and higher , because he wanted to put the new $$$ short block in... but the old Mule engine wouldn't die!!