I decided to pull the beast from her winter resting spot yesterday. Finally some nice weather. Started right up after a few rotations like usual, idles great, seemed to be running "good" (that is, as "good" as it was when I put put it in storage last year anyway) It ran - and reliably but was not tuned so great and restarts were always hard - small tick under the hood that I suspected was a exhaust leak. I let it warm up for 5mins and checked all the fluid levels and tire pressure - looked good. So we went for the short 3 mile drive back home...

I was not using much throttle, just babying it, no high RPMS or anything then after about a mile I hear a pop and a extreme exhaust leak. Pulled over and look what I seen under the hood!!! (sorry the picture looks overexposed on the top half, the sun is bright but not on the hole)







WOW..... That had to take a lot of pressure.. wtf?.. I put that butt plug in the EGR port on the header years ago and never had a problem, never tightened it since, didn't put to much muscle into it when I did tighten it originally... it didn't even pop off at the threads, OR the WELD!. that is straight up pipe. It wasn't even up to temp. The exhaust is pacesetter shorty headers, completely gutted cat, into a 3" bullet style muffler (straight threw pipe like a cherry bomb or bike pipe) then a SLP loudmouth (original) catback. Perhaps this Frankenstein is more restrictive than I think.. or something is clogging it up. Maybe something nested in there over winter, but it ran the same as before. At any rate its time for a exhaust overall. I HATE these headers, cant get to the bolts well - cant get to the plugs well.. any recommendations on headers? Thanks


I am amazed that pacesetter would just stick the pipe in the hole and weld it, look how deep it goes into the pipe adding restriction.

 

I vote crappy workmanship on the headers.

 

that awesome! and bad at the same time.

ya that pacesetter design is stupid.

Go buy a set of a pacesetter longtubes with no EGR bungs, they are labeled as off road use only, but you are clearly not using the egr stuff anymore anyways.

 

nope, no emission testing for pre 95 (OBD1) vehicles here. The next headers will be off road use only (no EGR bung to leak or restrict flow). This will give me a change to change the spark plugs, run the wires nice and neat, and clean up any exhaust leaks. I think I have heard of people doubling up exhaust manifold gaskets - if that is acceptable I would like to do that.

Do the long tubes leave more room for plugs and easier access to the header bolts?



I sure hope all my tuning issues were the result of air leaks before the O2's and a restrictive exhaust.

 

I do not think your exhaust was meaningfully restrictive.
The fresh air leaks before the O2 will cause tuning hassles.

 

Wow. How does that happen? Hopefully you'll have better luck with your next set of headers.

 

I know that will but I never found exactly where it was leaking before this happened, I didn't detect any leaks there. I hope it WAS leaking and that was causing problems before this happened..

but you think even with a non restrictive exhaust It could still blow off that part of the header? Even with a proper exhaust setup high pressures are still present that close to the head? thanks

 

I agree.. This seems almost impossible to create that much pressure and have it fail that way.

 

I think the metal was fatigued and cracked, sure an exhaust pulse unseated it but that is not what broke it.

 

Those headers do look kinda rusty and with that bung welded in the way it is, it prolly has had exhaust pressure on it for any number or years and finally gave way.

 

That is not for EGR, it is for AIR. Nevertheless on what caused it (Dwayne has plausible ideas), you now can claim to be the first to have a cutout on your #1 primary tube.

 

lol. Oh man your right. You are the man Shoebox (cant thank you enough for the info you provide on your site) not to mention your uber knowledge on the forum - your right that is not EGR its for AIR INJECTION. TY.

So the off road use only Pacesetter long tubes wont have EGR or AIR ports right?

 

Correct, I have a set on my 1997 SS. They will just have o2 bungs at the bottom

 

Perfect, Thank you. How would you rate them for spark plug removal and access to header bolts for installation in the car.


Anyone ever double up exhaust manifold gaskets before?

 

Good catch shoebox I didn't even pay attention.