I have been tuning my 05 mustang with a predator tuner for a few months now, trying to get it just right, but since the fuel here is kinda hit and miss as far as quality i will get some chatter up around 4-5000 rpms.

it is only brief, and not very often, but it happens from time to time.

I have rolled timing off a degree at a time to get it so it is very rare, but once in a while it will chatter.

my question is how bad is it hurting the motor when it does this, and do you think it has already caused major damage?

the motor pulls harder than ever as it is now, and i have dialed the timing back two degrees from where it was pinging (not really a knocking sound but more like a fast metallic chattering) and it has not happened since. Do you think it has hurt the motor?

 

I was going to say you're probably running too much advance for the fuel you've got, but then I got to your last sentence and you already discovered that.

I wouldn't worry about the motor being hurt with the little bit of pinging you describe, and now that you've retarded the timing and stopped it you're in good shape!

 

 

I am running 91 octane gas with a predator 91 octane tune. I have a mac straight shot intake, and have richened the mixture by 4 points, advanced global timing by 1 point, and retarded 2-4000 rpm timing by 2 points, and 4-7000 rpm timing by 3 points.

It seems like it only pings when the rpms are above 4000 rpms at wide open throttle, when i have a passenger in the car (i figure the added load on the motor is what is inducing the ping) I just filled the tank and the ping went away, but i am going to roll off some timing anyway.

I will dyno it this weekend with a wideband as well. I heard that this motor makes the best power when the timing is 35 degrees advanced at WOT and the air fuel ration is in the 13:1 range, does anybody have any input on this? I am taking it to a dyno shop, but the place is not a predator dealer so i have to tune it myself.

any help would be appreciated.

what is the actual soud when it is "detonating" is it the valve making contact with the piston?

 

Faber,
Detontion or pre-ignition is when the fuel charge is exploding or firing before the proper time. Some people say it is like hitting the top of the piston with a hammer. The piston is still on the way up an the fuel charge is firing and pushing back down before it should. It is all a matter of timing ( no pun intended ). If the detontion is strong enough it can and will crack the top of the piston at the ring grooves or wrist pin. As I have said I got greedy with a 96 Cobra and shatter 5 pistons at the track. Be careful!!!!!!!! Back your timing off or get better fuel. I could not here mine when it blew.
Scott :nono: :nono:

 

The best analogy I've heard is ball-bearings shaking in a tin can. Don't ignore it, in an unboosted state you probably won't grenade a rod or anything. More likely, you starting pecking away at the upper ring land and rings, eventually losing compression.

One thing many people do is run a tune that is one or two octane points lower than their available fuel as a safety measure. So, if you have 91octane, run an 89octane tune. You probably leave 5rwhp on the table, but your engine will thank you in the long run. Sounds like you may have done this in effect by dialing back your timing.

 

I think you are running lean get it on a dyno and you can see.My 05 was doing the same things without the cold air tune set up right.I would try to add some fuel
2-4 2.5 richer 4-7 5. richer that was my fix.

 

I think you are right, dialing the timing back 1 degree at a time has not yielded very good results as i still hear a faint ping in the higher rpm's

I will add more fuel and post the results.

I got a CEL last night and the diagnostics said it was too lean. I recently upgraded my predator to the latest rev (R21 i believe) and these problems started.....methinks diablosport did some tweaking to the tunes...

thanks for all the help guys!

 

try my settings you cant go wrong even if is a little rich.

 

Not familiar with the Predator tuning, but when you add fuel is it across the board (hence the "global" term), or can you add fuel in specified areas (like 4,000 rpms to redline)?

 

Of course they did. If you're going to upgrade the firmware of the tuner, don't use any of the modified settings from your last tune. This is one reason I haven't upgraded the tuner, because it's rockin the way it is on R8. Although it appears things have settled at 21 for awhile, I just may give it a whirl in a couple of week's.

If my memory serves me correct you're in Tuscon right? What's different about the gas down there? It's the same stuff we have up here.

 

Stupid arizona gas........

 

are you running 91 octane (or what they seem to label 91 octane)?

I cant run the 91 octane tune without pinging, i have the 87 octane tune in at the moment with 4 points of fuel at 2-4k rpm and 5 points of fuel at 4-7k rpm. with this setup the ping is gone, but if i advance the timing i am sure it will come back.

so from my point of view i believe the octane rating of the gas is not as high as the label says it is, or some of the ethanol or methanol that they add is not doing any favors to the octane rating.

so i am sure the gas is just junky...

 

I've been using 91 Octane up here with no problems, in fact I've actually added a little timing with no issue's either. I haven't been picky with the gas either, Diamond Shamrock/Arco/Texaco is what I've been using depending on who's got a better price closer to me.

I think the upgrade might have gotten a little more aggresive with the tune. I'll find out when I get around to upgrading mine.

 

every time your spark advance goes up up the more fuel you need in the upper rmp range more so .So start clicking advance from the 87 tune and add fuel .Your intake may be why your going lean you need more fuel. i had dynoed mine with the c@l intake without the diablo tune and it was lean as could be .If you can put it on a dyno and add fuel where you need it. Or try the diablo c@l tune download it at diablosport.com

 

I was told that shell, and mobil have the best quality fuel, and also chevron when you can find one, but who really knows....

thanks for the input porsche! I am pretty new to this computer tuning stuff (used to old fashioned points and condensor, centrifugal advance, destributors, and carbs...)

I will try what you suggested! I am going to have it dyno'd and widebanded on saturday, but the guy is not a predator dealer so this info will come in handy.

on a side note....

RICE for lunch!

I spanked a Lancer EVO MR (redemption from the other day when i spun my tires and got beat by one)

anyway...

thanks for the help fellas!