331 pinging at 4krpm

[86bluecobra]

http://forums.stangnet.com/showthread.php?t=609627 look at this post for a cheap ish wide band.

 

[86bluecobra]

I bought my LM-1 with RPM from http://www.yourperformancesource.com...nfID=41&Page=1
Use discount code inn20 and it's $343.20 shipped with the rpm converter.

 

[IntenseBlue]

Crank the timing up. I think the pinging sound you may be hearing is lots of excess unburnt gas igniting in the exhaust.

 

[Michael Yount]

"....lots of excess unburnt gas igniting in the exhaust."

Uh - that doesn't sound like 'pinging' --- it sounds like what it is -- a big back-fire.

 

[IntenseBlue]

I'd noticed my car running very rich. Turned out to be a o2 sensor unplugged, but it was rich enough to make my Hpipe and headers glow cherry red at night and I NEVER had a backfire.

Not saying the rich condition is his problem, but I'd definately look into it. Too low of timing can make it ping under part throttle, also.

 

[MustangPunk302]

I'd noticed my car running very rich. Turned out to be a o2 sensor unplugged, but it was rich enough to make my Hpipe and headers glow cherry red at night and I NEVER had a backfire.

Not saying the rich condition is his problem, but I'd definately look into it. Too low of timing can make it ping under part throttle, also.

I'll assume you have cats, and they are now longer good...

 

[IntenseBlue]

Cut them out afterwards and it quit glowing, but didn't notice the o2 sensor unplugged until after tranmission gave out and I found was taking the H-pipe off.

 

[HISSIN50]

IB, I think he is running a carb and probably does not use lamda feedback.

As Michael said, unburned fuel igniting in the exhaust makes a popping type noise.

 

[IntenseBlue]

I know he's running a carb. Mine was bad enough to make the hpipe glow red at night and I never had any pops.

Also, too little timing can make it ping under part throttle conditions.

 

[HISSIN50]

Also, too little timing can make it ping under part throttle conditions.

This is new to me. Can you please explain the dynamic at hand for those of us (like me) who don't understand how this can happen. Thanks.

 

[IntenseBlue]

I'm not sure what causes it, but my dad's truck, which is Vortech supercharged with a Crane timing retard will ping like hell under part-throttle conditions with the timing turned down low. It won't ping in higher rpms if under full throttle, but it'll ping. If it's got too much timing, it's fine down low and under part throttle, but will detonate under full throttle, mostly around 4500rpm or higher. It's a pinging sound when there isn't enough timing though. It sounds like someone slapping the intake with a yardstick when there is too much.

 

[Modular2v]

i really wish i knew where to start with the jets

 

[HISSIN50]

I'm not sure what causes it, but my dad's truck, which is Vortech supercharged with a Crane timing retard will ping like hell under part-throttle conditions with the timing turned down low. It won't ping in higher rpms if under full throttle, but it'll ping. If it's got too much timing, it's fine down low and under part throttle, but will detonate under full throttle, mostly around 4500rpm or higher. It's a pinging sound when there isn't enough timing though. It sounds like someone slapping the intake with a yardstick when there is too much.

That seems like a tune issue that is not going to correlate to Mod's car or state of tune. Things like that can happen with load-based computers as well, but again, it doesnt apply to the situation at hand (which is, in however a roundabout way, trying to help Mod).

 

[bluevenom867]

i really wish i knew where to start with the jets

Try a 100hp shot,and if you need jet info;just go look it up on Holleys web site:

www.holley.com

It will be under tech page.

 

[IntenseBlue]

I think he was referring to carburetor jets.

 

[Modular2v]

I think he was referring to carburetor jets.

yes i was......i know what jetting to start out with on nitrous. . Im just so use to fuel injection and a carb is alltogether another world but i need to learn

 

[bluevenom867]

yes i was......i know what jetting to start out with on nitrous. . Im just so use to fuel injection and a carb is alltogether another world but i need to learn

Well,still...www.holley.com