iceman Posted November 6, 2021 Report Share Posted November 6, 2021 Hi, Trying to get a decent first start from my 6.0L GM V8 running a G4 Storm Black in traditional mode. So far only had a few seconds of erratic running with a hard start initially, now only pops and bangs... Initially a 2006 L76 but now with AFM hardware removed and a better cam and related fitted so now basically a warm L98. Running the gen4 58X trigger system. Modified OEM engine loom, OEM injectors, coils, MAP sensor but cable throttle, NZEFI IACV and IAT. Cam and 3 bolt sprocket are part of a set supposedly for an L76 AFM delete so assume the sprocket has the correct trigger pattern for the original L76 configuration, if that makes a difference. Trigger offset confirmed at 0 degrees (TDC mark). Going by the initial erratic start and having tried adding 360 degrees and the alternative Chev LS2/LS6 90 degree trig option without noticeable improvement, I think I'm OK in my current trigger settings. However, the trigger 1 signal is constantly YES in the runtime values when cranking but trigger 2 is YES then NO (steadily) as the engine is cranked over, so something maybe up there? Files attached for viewing and advice please. Cheers, Pete. First start issue.llg Trigger Scope Log 2021-11-6 3;31;51 pm.llg LS conversion.pclr Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 6, 2021 Report Share Posted November 6, 2021 It definitely isnt happy about something with the trigger. Can you do another couple of triggerscopes, that first one didnt capture a full 2 crank revolutions so I would like to see the other revolution before making a suggestion. Quote Link to comment Share on other sites More sharing options...
iceman Posted November 7, 2021 Author Report Share Posted November 7, 2021 Hi Adam, Two more scopes attached thanks. These are about 15 seconds long each on the starter. Cheers, Pete. Trigger Scope Log 2021-11-7 1;17;59 pm.llg Trigger Scope Log 2021-11-7 1;14;31 pm.llg Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 7, 2021 Report Share Posted November 7, 2021 It looks like the LS2/LS7 90 offset mode would work fine with this. Can you change to that mode and give us a log of it cranking. Quote Link to comment Share on other sites More sharing options...
iceman Posted November 7, 2021 Author Report Share Posted November 7, 2021 Adam, Definitely sounds closer to a start with the 90 deg offset setting and trigger 2 is now a solid YES while cranking. A couple more scopes attached. Master fuel around the mid 30's seems to get the most promising noises...Any other settings I can play with to get a decent start? Cheers again, Pete. Trigger Scope Log 2021-11-7 1;17;59 pm.llg Trigger Scope Log 2021-11-7 5;52;02 pm.llg Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 7, 2021 Report Share Posted November 7, 2021 I really just wanted to see a log now to confirm everything else is happy, not a trigger scope log. Quote Link to comment Share on other sites More sharing options...
iceman Posted November 7, 2021 Author Report Share Posted November 7, 2021 Further.... Just noticed you asked for another log rather than scope so new log attached. Interesting that this time the trigger 2 has gone back to cyclic YES then NO while cranking...Just about started again on first crank but then nothing after further cranking. Log 2021-11-7 6;07;13 pm.llg Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 7, 2021 Report Share Posted November 7, 2021 What size injectors do these things have? Whats the engine capacity? Quote Link to comment Share on other sites More sharing options...
iceman Posted November 7, 2021 Author Report Share Posted November 7, 2021 6.0L, 440cc Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 7, 2021 Report Share Posted November 7, 2021 Yeah, trigger is not happy again in that one. If you watch RPM you will see it is not happy as it drops to zero about once per cam rev. Did you do a store after changing the trigger mode? Is it still on the correct trigger mode? Quote Link to comment Share on other sites More sharing options...
iceman Posted November 7, 2021 Author Report Share Posted November 7, 2021 Hi Adam, Yes stored the new trigger mode but later realised I hadn't checked/reset the timing offset with that change. Had to add 35 degrees to get back to the TDC mark I am using, got good triggers again and it burst into life. Now to fabricate an exhaust system to keep the neighbours happy before going any further... As always, excellent customer support thank you. Pete. Quote Link to comment Share on other sites More sharing options...
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