Author Topic: few questions about secondry triggering  (Read 4919 times)

Offline Seight-v8

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few questions about secondry triggering
« on: December 02, 2010, 11:01:29 am »
hello all,

Got a few days off work due to a few flakes of snow outside my house...lol. So started some winter upgrades early.

Thinking about secondry triggering on my 4.6 v8 and i have more questions than answers.

1. The Piper 285 cam in my engine has the following specs on the inlet valve, starts to open at 30 BTDC and is closed at 70 ABDC (280deg duration), but where best to put the trigger on the cam sprocket....will TDC be any good?.

2. If i put the trigger at TDC on the cam sprocket.....can i change it later in the software somehow????....or would it mean a mod to the sprocket???.

3. I have wasted spark so 4 ignition events per revolution, 720deg for the full v8 firing order......how do i set the injector events in vemstune.....??

4. How much gap in the cam sprocket is needed for a good pulse for the sensor???....as its a hall sensor 1GT101DC (honeywell)...at the moment the gaps are about 50deg...is this too much???

Sure this is easy when you know how....took me a few days to get this far....

thanks for any help

scott
Engine:Rover V8 4600cc
Vems Firmware:V1.2.38, GPS, SDcard, LCD & Dual lambdas, Wasted spark, 36-1 trigger, Cam Sync & Bluetooth serial.

http://www.vems.hu/wiki/index.php?page=MembersPage%2FScottRichmond

Offline Seight-v8

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Re: few questions about secondry triggering
« Reply #1 on: December 02, 2010, 11:59:57 am »
hopefully i propose a new trigger wheel like this?

Set with the trigger at TDC....the slot is 50deg in angle.



scott
Engine:Rover V8 4600cc
Vems Firmware:V1.2.38, GPS, SDcard, LCD & Dual lambdas, Wasted spark, 36-1 trigger, Cam Sync & Bluetooth serial.

http://www.vems.hu/wiki/index.php?page=MembersPage%2FScottRichmond

Offline mattias

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Re: few questions about secondry triggering
« Reply #2 on: December 02, 2010, 01:48:57 pm »
You don't specify what primary trigger you have, should I assume 36-1 ?
In the case of missing-tooth, the cam sync pulse (either rising/falling) must not race with the missing teeth. It can occur any time but not there.  Trigger tooth count is relative to the missing-tooth appearing after the cam sync pulse.

Set the injector events to match the ignition output table (cyl 1 ignition = cyl 1 injection).
400-450 degrees seems to be good starting values for the injector timing.