[cfiiman]

Hey all,

I have a question for you expert tuners out there...My mustang (a 90lx 5.0 conv.) is detonating I believe under a load, say pedal down and rolling through like 3k rpms...I'm embarrsed to say that in the almost two years i've owned it I have never given it a tune up...I just don't drive it that much...But today I got a wild hair and decided to check the timing b/c I believed that was the problem...When I checked it with the sensor unplugged the base timing was set at 12 deg. BTDC...The car is bone stock by the way...Anyway I turned the distributor clockwise (Haynes manual said that is how to retard timing) and it bumped the timing to 14 deg. BTDC and test drove it, it didn't seem much different...So I went to about 16 deg...Didn't really notice anything different, then went to about 18 deg BTDC and the problem (pinging noise) seem to get worse, or at least come on earlier than 3000rpms...So I'm stumped am I actually advancing the timing instead of retarding it???...Should I go beyond 18 deg. or am I going the wrong way...A tech article I read on here said when the numbers go up say from 12 to 14 degrees that I am advancing the timing, but my stupid Haynes manual said to turn the distributor clockwise to retard teh timing and when I do the numbers go up...So I am in the middle of a contradiction and now I am really confused...I know at 18 degrees the car seemed to do it worse...I just set the timing at 15 degrees before I packed it in tonight and decided to ask on here for help before I try to do anything else...What are your cars set at...Could other things like needing plugs/wires/cap/rotor/air filter be causing this problem regaurdless of the timing and I need to do all that tune-up work before even attempting to set the timing...Please help I'm really frustrated, Ford says that it is "spark knock" and it is normal and that even new Cobra's do it...From some discussions in the "power adders" posts I believe Ford is full of SH#T...Oh and I always run premium fuel btw...

Thanks for any help,

Jason

 

[cfiiman]

Re

Hey all,

I just found about 4 websites that say when you move up the BTDC scale you are advancing the timing...I'm so pissed...And I feel stupid too...Anyway why the hell did my Haynes manual tell me to turn it Clockwise to retard the timing...That is what confused me...These sites also said that the stock setting is 10 deg...But that many come set at about 4-6 degrees BTDC...That would make sense why I didn't see anything different and it actually go worse...Where should I set it...I run premium fuel so I don't know why at 12 degrees it was ever pinging then, unless it was the other stuff I mentioned in the above post...I'm going to set it down to 10 degrees and see what happens...Is this normal for a 5.0 to ping with premium fuel and 12 deg of timing????...Should I go down to 4-6 like the articles were saying some 5.0's come???? Please help me out...

Thanks,

Jason

 

[cfiiman]

Hey Guys

PROBLEM FIXED!!...Thank Goodness...Took the timing down to about 9 degrees before tdc and went out and stomped the crap out of it and nothin but clean sounding power...No more marbles in a can around 3k rpms...I'm so freakin happy...This has been bugging me for a year!...Question now is, should I continue to run the high octane fuel...Or should I but the timing down another few notches and run lower octane...Money is not the issue I am fine paying for premium...But would anyone do that or just leave it where it is now that it is sounding great and NOT FREAKIN PINGING!!! :kooky:

Jason

 

[GhostDog 5.0]

10 Degrees is the base timing setting after TDC. to 12-14 for added performance but watch for pinging and use better gas.

You should be able to run 10 degrees with regular gas without pinging.