Quote:
Originally Posted by RBYCC
11.5 bar/cyl compression is within range...minimum is 8.5 bars.
M103-12V is 9.2:1 CR which is almost optimum for a turbo engine.
My M103-12V is at 12.9 bar/ 190psi per cylinder.
Main things that would cause detonation are too low octane, too lean AFR or too much timing.
You indicate fairly rich AFR's which should support timing advance.
What octane gas are you using ?
Ed A.
|
Ed, I'm currently using 95 octane (euro rating) and will try 98 octane when this tank is done. I pulled back the timing to 5 degrees but could still here the same noise around the same rpm. Now the question is , is it really knocking , also if it's knocking could it be from the spark plugs (using the standard heat range with resistors), or from a weak spark, say the coil doesn't have enough charge time ?
Quote:
|
Originally Posted by Bluefang
Are you sure it actually knocking, and not just a bad signal from the Hall sensor. When i first installed my 36-1 trigger wheel i put the reading sensor too close to the wheel and it ended up distorting the signal when it went over 4.5k rpm and it would miss like hell and have a knocking noise to it as well.
|
Well to be honest I'm not 100% sure but it sounds like knocking. It doesn't make sense (to me at least)....alright its knocking with 24 deg. timing advance (NA was running 29 deg.) but then I started pulling the timing and backed it to 5 deg. and the sound was still there. Also it doesn't feel like missing, although I lift off
immediately when I here the sound, also it run fine with no missing in NA form all the way to 6300 rpm (rev limit).
Quote:
|
Originally Posted by JayRash
Off topic, but is the car missing the left firewall!!!!! ????
|
Jay, all firewalls are in place none are missing . I have to tidy the engine bay, but want to get it running right first :-)