[IZZY1111]

Hey guys, first post.

I recently swapped for the 4.2 engine and have been trying to resolve a pinging issue on hard accelerations. Ive been searching all over the net for the specific degree the spark in the regular 3.8 ignites Before top dead center, so i can figure out how much to retard the spark in comparison for the 4.2L, Does anyone know, it would really be apreciated.

 

[heavy metal]

Welcome to the site!!

 

[JonR2006]

I do not know the exact spark advance but I would start at 10 degree global advance BTDC at idle for a good starting point.

What compression ratio are you running? What octane are you running? Are you running lean? Are you tuning this yourself?

 

[B.Cooper]

Welcome to AFM!

 

[IZZY1111]

I do not know the exact spark advance but I would start at 10 degree global advance BTDC at idle for a good starting point.

What compression ratio are you running? What octane are you running? Are you running lean? Are you tuning this yourself?

Thankyou for the welcomes.

Im running 93 octane(tuned), I am not running lean or rich (no CEL to tell me otherwise), I have no idea what compression ratio its jumped to from 3.8 to 4.2. Im trying to tune it myself because I've ordered tunes from Bama for the 4.2 block but it doesnt seem to run as great until I retard the global spark a couple degrees myself. But im still getting pinging on hard acceleration and feels like should have more power. Right now I have retarded it by 3 degrees, it seems if I go beyond this I noticed bad gas mileage, and still noticeable pinging.

Any ideas are welcome, I have a '95 V6 mustang now with a 4.2 block and 80mm MAF, 65mm TB, 24lb Injectors, CAI, 180 thermostat, Windstar Intake manifold (Splitport Heads), Underdrives pulleys, Aluminum Driveshaft, 3.08 gears.

 

[baddbradd]

Is it the stock long block?

 

[6stang02]

Do you have an egr on the car? Does the car believe that there is an egr? I had this issue on a mazda/ranger i worked on where i accidentally ran the egr vacuum lines ontop of the manifold and it caused it to sound like a freakin diesel it was pinging so bad. Either way, it might be something to look at.

 

[IZZY1111]

Im not sure what you're referring to with long block. I got a 4.2 block which included the pistons, crank and camshaft. I used the same heads and other components from the old 3.8 engine.

I believe it does know that it has the egr because I've had issues with it before resolving egr trouble codes which are now fixed. I managed to install the egr regularly to the lower intake.

 

[wmburns]

It seems to me that the 4.2 should be set up the EXACT same way as the 3.8 with regards to initial timing and cam sensor sync. The reason for this is a PCM controlled ignition timing. The PCM depends upon the timing set to a known point.

If a different timing curve is needed, this should be handled with a PCM tune.

+1 on the EGR suggestions.

Pinging could also be a sign that the cam sensor isn't sync'ed correctly.

 

[IZZY1111]

The camshaft synchronizor was just replaced, Im using the original style from a '95. It should be aligned good, I was getting idle surge problems before I replaced it.

The PCM is supposedly tuned with my SCT tuner with a custom Bama tune. I can still make certain adjustments with the tuner though.

EGR is operating good, but I did forget to mention I removed my PCVvalve system (because I got tired of oil seeping into the intake) But would that make a difference?

 

[wmburns]

EGR is operating good, but I did forget to mention I removed my PCVvalve system (because I got tired of oil seeping into the intake) But would that make a difference?

How are you venting the crank case vapors? EXPECT problems if not venting the crank case vapors.

If PCV venting using outside make up air, the extra un-metered air can cause a lean condition.

There is a redesigned V6 valve cover PCV baffle that addresses the excessive PCV oil blow by problem.

http://www.allfordmustangs.com/forums/v6-tech/313594-1999-ford-mustang-3-8-a.html

 

[IZZY1111]

The vapors are venting into outside air, but I doubt there is an issue with unmetered air entering the intake because I have the inlet where the hoses would go plugged off.

The link seems to go to another type of engine trouble topic.

 

[wmburns]

The vapors are venting into outside air, but I doubt there is an issue with unmetered air entering the intake because I have the inlet where the hoses would go plugged off.

The link seems to go to another type of engine trouble topic.

Where do you think the air that is being vented came from in the first place? It's a mass of air that passed through the MAF sensor. Therefore it was measured and accounted for. If vented straight outside, then the mass of air is lost.

Bottom line. The PCV system needs make up air to balance the air leaving the system. That's why in a factory system the make up air comes from the intake and the outgoing vapors also go to the vacuum side. The net effect is the amount (mass) of air metered by the MAF is accounted for.

The tune needs to account for the difference. IMO removing the PCV system is a band aid symptom fix and not solving the real base problem.

I don't think that you read all the way down to post #8

 

[IZZY1111]

I saw the posted link now, I'll try one of those inline filters.

 

[baddbradd]

Make your own oil/air separator or spend $150 and get a good one. My homade one does pretty good....intake is much cleaner--almost dry. He's right though, that air has already been metered

 

[IZZY1111]

I got some of those inline filters at Autozone. And it does seem to make some good effect. I still hear pinging, but very faintly though. So yeah good work.

Just still feels like hard acceleration should pull stronger compared to how better it pulls on light acceleration.