Randall Posted February 19, 2013 Share Posted February 19, 2013 Here is a data log of my first start up of my 76 280z. I think my fuel pressure is not consistent (probably need more fuel in the gas tank) Let me know if you see anything that sticks out. Link to my car specs is in my signature. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted February 19, 2013 Share Posted February 19, 2013 I don't see your datalog. Did it start on the first try? If so you must have really done your homework. Does it run good? Have you driven it? Congrats Quote Link to comment Share on other sites More sharing options...
Randall Posted February 19, 2013 Author Share Posted February 19, 2013 Sorry guess it didn't upload.... Yes it did start on about 2nd 3rd crank. I used cygnus's tune since he has a pretty similar motor setup... It ran ok vacuum was only about 11 or 12 and afr seemed to slowly lean out but thats for sure a fuel supply issue... The only 2 things I am concerned about are: 1. i topped the motor off with oil and cranked the motor to prime it with oil, especially the turbo. (i waited until i saw oil coming out of the oil feed for the turbo. At this point everything cranked fine. But when i started to get the distributor set to match my offset in megasquirt the motor would start to kick back every now and then like you would see when you have the advance set to high. Maybe im just getting some noise while cranking that is sending out a weird spark? 2. when i prime the system it hits 40 psi or so then will slowly drop to a little above 20 psi then if i come out within an hour or so it will be at 0 psi. I don't believe the injectors are leaking because they where not leaking when i bench tested them. So that leaves me with either the fuel pump is bleeding pressure which i also do not believe to be the case because i can disconnect the pre-pump filter and just a little fuel will come out when i still have pressure. So that leaves the stock FPR that i used? Unless this is normal? Also in cygnus's tune he has a req_fuel of 9.1 but mine calculates to 7.2 but we have the same injectors except my motor is bored over .40 and his is .20 Quote Link to comment Share on other sites More sharing options...
Randall Posted February 19, 2013 Author Share Posted February 19, 2013 Keep forgetting to attach.... First_Start.zip Quote Link to comment Share on other sites More sharing options...
OhBilly Posted February 19, 2013 Share Posted February 19, 2013 What wideband are you running (your link isn't working so I couldn't check)? It looks like you're getting some noise on the wideband line but it may be that I don't have the parameters in Megalogviewer correct for your setup. Your AFR leaning out is expected because your afterstart and warmup enrichments will taper as the car warms up. I don't see anything in the datalog to suggest a fuel supply issue. The kickback issue: After you got the car started did you verify your actual timing and the timing reported by MS correspond? What is your cranking advance? The neighborhood of 10* BTDC should work pretty well. Do you have a priming pulse set to something other than zero? If so, your initial cranking to prime it with oil could have dumped a fair amount of fuel in the cylinders. If that's the case, maybe the kickback was actually a bit of hydrolock....? I'm not sure how the stock FPR works, but unless it has a built in check valve you will bleed pressure pretty quickly through the return line. I have an Aeromotive FPR and mine behaves pretty much exactly like you've described. Quote Link to comment Share on other sites More sharing options...
Randall Posted February 19, 2013 Author Share Posted February 19, 2013 Yeah it's an LC-1 wideband. I cranked the car without the fuel injector fuses and the pump turned off. At a cranking speed of 300 I set the distributor to 0 using an offset of 60 with timing table set to all 0's First cranking timing I tried was 5 btdc and I had some kickback while cranking so I then changed it to 0 btdc and had two kickbacks as you can see in the log while cranking. I will change it to 10 btdc and see what happens. I think I will also pinch the return line just to make sure but I'm pretty sure fpr is bleeding because after it bleeds if I pull the plugs and crank no fuel blows out of the cylinders. Quote Link to comment Share on other sites More sharing options...
OhBilly Posted February 19, 2013 Share Posted February 19, 2013 It's unclear what you mean by "I set the distributor to 0 using an offset of 60..." Does this mean that you set Megasquirt cranking advance to 0, then cranked it over while strobing it, and it strobed on 0 at an offset of 60? If so, that's a good sign. But once you get it running, you'll also want to strobe it to verify accurate timing. Set it to fixed timing at somewhere around 20* BTDC and get her started and idling. Then strobe it to verify it's actually firing at 20*. I think the FPR bleeding pressure through the return line is normal, at least it is on mine. Quote Link to comment Share on other sites More sharing options...
Randall Posted February 19, 2013 Author Share Posted February 19, 2013 Yeah that is what I meant. Timing was fixed to 0 in the table and trigger offset was set to 60 then I turned the distributor until I saw 0 while cranking. It was late last night so I have not verified timing while it was idling Quote Link to comment Share on other sites More sharing options...
NewZed Posted February 19, 2013 Share Posted February 19, 2013 Old stock factory FPRs tend to leak down. They're not supposed to though, I think the valve just stops seating right after many years or rust holds them open. I've checked a bunch and found a few that don't leak down for days. I have one on the car now. The Aeromotive FPR design just doesn't hold pressure once the fuel pump shuts off. It regulates fine, just doesn't hold when flow stops. They're aware of the problem (I've emailed the company and received a reply). The other source of pressure leak down is the check valve in the fuel pump. They fail occasionally. Quote Link to comment Share on other sites More sharing options...
Randall Posted February 19, 2013 Author Share Posted February 19, 2013 (edited) It's a brand new walbro 255lph pump so it should be fine. I am positive its probably just the old FPR that I am using. The only thing that still concerns me is the random cranking problems I am having. Looking at the log you can see where the rpms dropped twice while cranking and the one that dropped to zero also corresponds to a voltage drop from 11v to 10v. I wonder if this could be a starter issue? Can't be hydrolock as it started after i started testing spark but before i started adding fuel to the equation... P.S. i fixed the link in my sig Edited February 19, 2013 by Randall Quote Link to comment Share on other sites More sharing options...
loy Posted February 20, 2013 Share Posted February 20, 2013 While cranking do you have a value greater than 0 in "Cranking advance (degrees)" in "more ignition options?" If so the timing while cranking will be off by whatever value that is. Quote Link to comment Share on other sites More sharing options...
Randall Posted February 20, 2013 Author Share Posted February 20, 2013 Yeah I had 5 in there when I set the timing so it is probably off by about 5 Quote Link to comment Share on other sites More sharing options...
Randall Posted February 20, 2013 Author Share Posted February 20, 2013 Well I finally got a second hand to watch the timing. On cygnus's tune with 60 degree offset in ms and distributor fully advanced I saw 5 atdc at 700 rpm AFR read at 9 I then changed the offset to 45 and was seeing 15 atdc and idle changed to 1200 rpm with an AFR of 12.8. What is strange is that it ran super with the 45 degree offset great vacuum smooth idle good throttle response but the timing is off. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted February 21, 2013 Share Posted February 21, 2013 (edited) When you used the trigger wizard did you set it to 'fixed timing'? Otherwise it's going to try to use the table and you'll have problems setting timing. I'm also using 440cc injectors and my required fuel is 7...ms. Edited February 21, 2013 by skirkland1980 Quote Link to comment Share on other sites More sharing options...
Randall Posted February 21, 2013 Author Share Posted February 21, 2013 yeah but i think my auto zone timing light is junk...finally borrowed my neighbors variable craftsman timing light and where mine said 5*ATDC this one is saying 10*BTDC so i finally get the car dialed in so that my timing matches what is commanded in megasquirt. Car idles great around 15-20 degrees but using the table is trying to call for 25 to 30 at around 1200 rpm Quote Link to comment Share on other sites More sharing options...
Randall Posted February 21, 2013 Author Share Posted February 21, 2013 Here is another data log. I believe MS was commanding around 30 degrees but i was seeing around 15 or so with the timing light. 2013-02-20_21.18.11.rar Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted February 21, 2013 Share Posted February 21, 2013 I recently had a thread with this problem. http://forums.hybridz.org/topic/110673-ms-2-v-357-spark-table-inop/ You have to be careful where your trigger wizard is. Here is a copy and paste from Matt when I was having this problem "Found the issue. Turns out you were right in the "forbidden" area for> the Trigger Angle for MS2/Extra. MS2/Extra has two spark modes when> running in Basic Trigger. If the Trigger Angle is 19 degrees or less, it> runs in "next cylinder" mode and uses each pulse for the ignition timing> on the next cylinder's spark advance. An angle of 20 degrees or more> pushes it into "This cylinder" mode, where the spark angle has to be> several degrees less than the trigger mode. To avoid this problem, the> spark angle must need to be less than 20 degrees, or 50 degrees or more" Quote Link to comment Share on other sites More sharing options...
Randall Posted February 21, 2013 Author Share Posted February 21, 2013 (edited) I recently had a thread with this problem. http://forums.hybridz.org/topic/110673-ms-2-v-357-spark-table-inop/ You have to be careful where your trigger wizard is. Here is a copy and paste from Matt when I was having this problem "Found the issue. Turns out you were right in the "forbidden" area for > the Trigger Angle for MS2/Extra. MS2/Extra has two spark modes when > running in Basic Trigger. If the Trigger Angle is 19 degrees or less, it > runs in "next cylinder" mode and uses each pulse for the ignition timing > on the next cylinder's spark advance. An angle of 20 degrees or more > pushes it into "This cylinder" mode, where the spark angle has to be > several degrees less than the trigger mode. To avoid this problem, the > spark angle must need to be less than 20 degrees, or 50 degrees or more" See that is what i was thinking and it makes sense... I have been trying to do that from the beginning. Setting the trigger offset to 60 and fine tuning the distributor but i think i was so far off that it made it hard. So i tried 45 offset and bammmm the car runs awesome but could not turn the distributor to get the timing that megasquirt was commanding. but i got it close before my battery died. Today i will try switching back to 60 offset and getting the timing spot on. BTW i did not have enough advance with the 2 distributor set screws on the distributor so i rotated all my plug wires 1 place clockwise to get the advance i needed. I dont know if my math is right but on the cap there is 60 degrees between each plug wire. And the distributor slots have about 60 degrees combined 30 for advance 30 for retard. So in order to get a 60 degree angle/offset you would have to center the distributor and move all of the plugs clockwise 1. Edited February 21, 2013 by Randall Quote Link to comment Share on other sites More sharing options...
Randall Posted February 22, 2013 Author Share Posted February 22, 2013 I don't understand I have a 64 offset and my timing light matched what ms was commanding. Turned the car off and now it won't start I'm getting 10 on the crank when cranking. Finally get it started and I can't keep it running Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted February 22, 2013 Share Posted February 22, 2013 You don't have to rewire the distributor. Set up the dizzy and oil pump shaft just like a stock set up. MS doesn't know where tdc is so setting trigger angle to 60 just means it's reading the next slot in the wheel. Also the turbo engine needs 24-30 degrees of timing at idle. Quote Link to comment Share on other sites More sharing options...
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