hello
i have a 2002 MC ss with the l36 sc kit from zzp.
so i got the headers installed with a tune up with autolite 103's i believe i had 104 before but i read they were fine. I'm feeling a significant loss of power. the car would peel out on demand before i installed the headers. now it barely screeches. i no they deleted the egr, but I'm wondering about this hose in the picture, should i cap it off or is it supposed to be connected to something. i think it was part of the egr setup.

thanks in advance

 

I have no idea what that tube is, can you take a picture from a different angle? Can you tell what the other end is connected to? I just can't think of anything that would need a rubber line down there, the only thing down there is the starter. I will say, if it is something you need, it sure isn't going to last long unprotected that close to bare headers.

I can also say for certain that it isn't part of the EGR. EGR stands for exhaust gas re-circulation - there is no way you could ever run exhaust gases through a rubber hose with plastic clips. The EGR only really has 3 things going to it: a wire harness on top, exhaust gas input (metal hose that feeds off the rear header), exhaust gas output (flexible metal hose that connects to the lower intake).


Also, if you can't hardly spin the tires (assuming you're running street tires), and the car feels like it has lost power - then perhaps you should take it back to the place that installed them to look it over again? Even without a tune, the headers wouldn't cause a massive drop in power - so maybe they forgot to plug something back in?


Any reason for running 103s? That's a pretty cold plug if your only mods are a top swap and headers.

 

Ill snap a pic in after work. I'll put up a vid up on YouTube and copy the link to maybe it'll show a few things. I'm gonna go back to the shop in a few days if they can't find anything that's not plugged I'm gna swap the spark plugs to 104. I already got into a fight with them cause of the fans they said it was too tight and broke one of the Dan grill guards that lil piece was lodged in by the fan motor and ended up messing one side up. Would u no if the map sensor from a 2004 sc monte is a 2bar? I have an aero force scan gaUge if that can help u out?
Thanks again. Love your monte build btw

 

I don't necessarily think the 103s are causing the issue - I just think they sound a little cold for your mods. It should still run ok for now, I would just think they'd foul up quicker than a little warmer plug.

The MAP sensor for an SC 3800 is referred to as a '2 bar', but the terminology can be deceiving. That doesn't mean that it reads ambient to +30 psi, but rather 1 bar is from absolute zero to ambient, and the other bar is from ambient to +15 (in round numbers).

If you've got an aeroforce, that could help diagnose the issue. The things I would be curious to see are: knock retard (KR) and LTFT/STFT numbers to see how dialed in the tune is. KR should be at or near zero at WOT, and the fuel trims should also be roughly zero if the tune is dialed in well throughout the various throttle positions. They're not always going to be exactly zero, but they should be fairly close.

If both of those look good, I'd look at how much timing advance is being run at WOT. Obviously if there is KR present, this number is going to really drop which kills power output. Also, if there isn't enough spark advance, power can really start to drop off.

Lastly, I'd be curious to see the primary O2 sensor values. The thing about a header install is if you don't get everything sealed up 100%, you can get some funky O2 readings which would then impact the fueling.

 

Agreed, I don't think the headers are an issue. Nor, the plugs. Perfect situation for an aeroforce gauge....and guess who's got one for sale lol