Black smoke at hard acceleration

essie*

Registered User
Hey Scer's first of all my car runs great. It's a daily driver new rebuilt engine installed by myself.However at hard accel WOT my co workers notice as I peel out of the parking lot after work.:D Black smoke comes out of the exhaust.The car idles fine,And I just got a smog test all good --but NOX too high.Sound familiar, my car has no egr valve.But thats another story. By the way ther is no C.E.L. associated with this problem.All sensors are all original equipment.91 sc man trans blk on blk.
 
Sounds like you are just blowing the carbon buildup out of the exhaust. Mine will do it if I don't get on it for a while.
 
Same here, I get the black sooty looking smoke on a WOT run. As long as its not white, or blue, and goes away when I let up, im not worried about it.
 
Sea Fome will work really well. I dont know too much about the SC's but I know on like my dads Dodge you can pour it into the throttle body. I cant do that on my 4.6 cuz its horizontle....lol. U can put it in the gas to help clean out the fuel system and crap. U might wanna try to pour it into your throttle body. It will eat it out and blow it out...lol. Another thing that it might be...do u have a desial bird? lol:rolleyes:
 
Hey Scer's first of all my car runs great. It's a daily driver new rebuilt engine installed by myself.However at hard accel WOT my co workers notice as I peel out of the parking lot after work.:D Black smoke comes out of the exhaust.The car idles fine,And I just got a smog test all good --but NOX too high.Sound familiar, my car has no egr valve.But thats another story. By the way ther is no C.E.L. associated with this problem.All sensors are all original equipment.91 sc man trans blk on blk.

It's normal to get black smoke at WOT (unburned fuel). Some of the computers were setup with very rich wide open throttle settings.

David
 
a/f GURU help?

>Some of the computers were setup with very rich wide open throttle settings<

Stock A/F is normally 11.0 for my 90 at WOT, and yes 11.0 could be the answer to all the questonss below,
but I have heard & read SC's successfully using 12.2.

Has anyone had any success/comments tunning higher than my stock air/fuel ratio's?
(without blowing HG's) perhaps using something like the below?

WOT with stock timing (30degs) with 10psi with NO reductions for ACT using 93 octane gas, ECT=180. What air fuel ratio for WOT?

WOT with stock timing (30degs) with 15psi with NO reductions for ACT using 93 octane gas, ECT=180. What air fuel ratio for WOT?

WOT with stock timing (22degs reduction for ACT) using 93 octane gas with 10psi, ECT=180. What air fuel ratio for WOT?

WOT with stock timing (22degs reduction for ACT) using 93 octane gas with 10psi, ECT=180. What air fuel ratio for WOT?

While we are at it, any A/F thoughts on part throttle?
 
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Just Be Careful

I had that same issue you got some blow by, which means you must spool the ~~~~ out of your supercharger, because you most likely blew a couple of piston rings, so just make sure you check your oil every day or so, because you could end up being like me and spin a bearing, i kno i kno i am an idiot, but it happens.

JUST BE CAREFUL
 
I had that same issue you got some blow by, which means you must spool the ~~~~ out of your supercharger, because you most likely blew a couple of piston rings, so just make sure you check your oil every day or so, because you could end up being like me and spin a bearing, i kno i kno i am an idiot, but it happens.

JUST BE CAREFUL




Im by no means new to the SC game but you spool a turbo not a supercharger. Broken rings result in blow by with loss of compression and have nothing to do with the bearings. Im not sure what your talking about
 
Sea Fome will work really well. I dont know too much about the SC's but I know on like my dads Dodge you can pour it into the throttle body. I cant do that on my 4.6 cuz its horizontle....lol. U can put it in the gas to help clean out the fuel system and crap. U might wanna try to pour it into your throttle body. It will eat it out and blow it out...lol. Another thing that it might be...do u have a desial bird? lol:rolleyes:

ok, on the newer EFI motors for sea foam, you pull off a main vacume line such as the brake boster hose and run the car with someone keeping the gas going so it doesent chug out on you. Then let the can run empty and shut the car down for about 10 minutes. The car will be hard starting for a couple minutes but when it fires it will go and run like poo for a few more. You will see more white smoke pour out of the exhaust than you will ever see in your life!!! make sure to have a video camera with you. I wish i did.
 
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