Your header flanges are suspect. What thickness are they? The lighter ones can warp and that is the most likely scenario.
The good gaskets are a must and you definitely do not want that front heat shield. It is a recipe for leaks.
If you get some surgical tubing, you can stick one end in your ear and probe with the other end while the engine is running. That will tell you exactly where your leak is.
Copper isn't a bad idea but it is normally used for boosted applications. The thick Felpro's should hold it. If not, some of the flame proof RTV will help as well.
Something tells me you didn't torque them down correctly, they shouldn't leak as long as they were tightened properly in the first place if the headers were surfaced correctly.
Steve
------------------ Technology is great when it works, and one big pain in the ass when it doesn't
Ive never had problems with Felpro myself, even on race cars. If I remember, dont stock Fieros bolt straight on with NO gasket. I see that on a lot of newer cars too.
Originally posted by rogergarrison: If I remember, dont stock Fieros bolt straight on with NO gasket.
No, OE included a gasket that was of better quality than both of those linked to, it contained a metal combustion ring at each port like what is seen on head gaskets/
No, OE included a gasket that was of better quality than both of those linked to, it contained a metal combustion ring at each port like what is seen on head gaskets/
I remember seeing the felpros having said ring****
I remember seeing the felpros having said ring****
They do......I just replaced a cracked front manifold on my '88 GT this weekend and used a Fel-Pro gasket that had a metal ring around the port hole. So far so good......no leaks at all. I almost forgot what the Fiero exhaust note sounded like without a leaky manifold!
I use the VW beetle gaskets. No problems in 4 years or more.
Spoon
------------------ "Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut
I turn the stud in tight, until it bottoms out in the hole, and then I torque the nut to spec.
Click torque wrench or bar? and when if it is a click was the last time you had it checked? and do you always turn it back down to 0 when you are done, if not it is most likely off.
------------------ "Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut
Originally posted by Boostdreamer: Is that 18 ft-lbs? Is there a specific pattern to tighten? I guess it wouldn't matter with individual gaskets like the VW ones, would it?
Factory spec is 18 ft-lb. The service manual doesn't seem to have a torque sequence. Although it would be wise to start at the center, and work your way out. The sequence I use is to start with the center port, then do the port closest to that, and finally the remaining port. It seems to work OK for me. But as always, YMMV.
I can't comment on the VW gaskets, because I haven't used them. But I would start with the factory specs (and the torque sequence I mentioned), and work from there.
Thought I would add a pic of a VW Beetle air cooled 1600 exhaust gasket on a 2.8 manifold. Everything lines up perfectly.
Jonathan
Okay, so I crunched some numbers. its actually cheaper for me to buy the vw gaskets over the felpro, and the extremely cheap victor reinz ones ARE NOT WORTH IT.
I feel they are the best, so far and so good. I had to remove the alternator and ac compressor (with aluminum bracket) to get to the manifolds. luckily I had studs (not). everything so far, so good. lol. I hear a slight ticking from somewhere, but I have yet to find any sooty exhaust leaking from the manifolds. probably a lifter (cold start) have a metallic composite crush marerial sandwiched in between two metal sheets with the crimps on the inlet with a slight rise (sealing ring) on both sides.
such a great seal. 10/10 I would recommend this to anyone, the work however is another story... XD they
over time the exhaust manifolds loose thier alignment,, the thicker gaskets compensate for this I place sand paper on a level surface & oscilate/rotate the manifold a few times then check to see if I need to sand them into flat level alignment. I did this as part of my efficient porting process often a concrete floor laid by a professional is good enough,,my kitchen counter has some strange wear??hmmmm check with a straight edge,like a construction level,manifold & floor
over time the exhaust manifolds loose thier alignment,, the thicker gaskets compensate for this I place sand paper on a level surface & oscilate/rotate the manifold a few times then check to see if I need to sand them into flat level alignment. I did this as part of my efficient porting process often a concrete floor laid by a professional is good enough,,my kitchen counter has some strange wear??hmmmm check with a straight edge,like a construction level,manifold & floor
I remember getting the guy at my machine shop to do this for me on his huge belt sander for when he surfaces heads.
It really helps to keep the exhaust manifolds from pulling un-evenly on the exhaust bolts/studs after they are installed. because sometimes the header's will "warp" from the heat and the flanges don't all end up sitting level on a flat surface.