I'm tired of my car smelling like exhaust (almost fainted driving once, smells bad, etc), and I'm convinced that my passenger side header flange is leaking. I unbolted it (shorty header of some sort) last night (and can't get it to fit out of the engine bay) and took off the old header gasket. Tonight I'm running by Autozone (on the way home) and plan to grab some exhaust gaskets. Everything I saw at first pointed to Percy's aluminum gaskets ~$30 at Summit, not sure at the local parts place. Then I found a bunch of posts like THIS ONE that said to just use manifold gaskets. Then there was the big RTV debate. As far as I know, my heaer flanges are strait, but I'm apparently not going to be getting it out of the car to check. 1) Will header gaskets actually work (car sees around 120 miles/day) 2)Red RTV, copper RTV, no RTV? I have both so it isn't a big deal either way. 3) Other than cleaning both surfaces and tightening the bolts from the center to the ends, is there anything else I should do? In case it matters: Unknown brand shorty headers (comon brand, just don't remember) 350 with 333882 iron heads (yeah, they suck, I've already been told). Edit: The gaskets match closely to the exhaust ports, and measure at 1.650 inches diameter.

It would only make sense for manifold gaskets to work on headers. You would probably have to trim the excess around the edges...

I assume being stock heads the gaskets will match on the inside already. Will it hurt anything if they stick out a bit on the outside? They already stick out on the header gaskets? Also, since these are round port heads, and most that I have seen are round, is there anything that I can do to help the guy at the auto parts counter ID them?
Perhaps a better question, if manifold gaskets are so great, what advantage is there to the more expensive header gaskets?

I tried using exhaust manifold gaskets for my headers on my LT1. The exhaust manifolds will have to be trimmed in order to work correctly. IMHO, just get a good set of header gaskets and call it a day. The exhaust manifold don't seal properly against the header and you will probably still have a leak.

Jay

Which part of the gasket are you trimming?

I trimmed the ends of the gasket around the rivet that holds the three pieces of the manifold gasket together. The reason being is because the bolts holes at each end of the header did not line up with the gasket so there was no way to get the bolt thru the gasket. I will see if I can take a picture or draw a diagram so you can visualize it.

Jay

That makes sense now, thank you. In case I end up getting a header gasket anyways, what about trimming the ports on those? The Percy's aluminum gaskets seem popular around here. I only have the gasket I took out with me, not that head or header, but it measures at 1.650" and the percy's gaskets are listed at 1.50. Is it worth trimming those out, is trimming the layered aluminum a bad idea, or is my current gasket simply too big?

JC,

If you get a gasket that is too small you will block your exhaust ports in return decreasing performance. If you get a gasket that is too big you run the risk having another exhaust leak. The best thing to do is take the header out to be sure that the gasket you have now is the correct size. Furthermore, I would not recommend cutting the layered aluminum just because it was made to be solid piece and cutting it would only damage the seal thus causing a leak. If all else fails I would at least try to match the gasket up with the headers.

Jay

Ok, that makes sense. I'll measure the headers with a pair of calipers when I get home, and then head to the parts place with those numbers and a pair of calipers. I think the headers are a pretty good match to the old gasket, but I'm not 100%.

Yeah you just want to make sure you do it right the first time so you don't have to do it twice.

Good Luck,
Jay

stock manifolds dont have gaskets. The manifold fits flush and thats the end of it

Dont fret too long on the exact size and shape of the port. Youll never get it perfect as headers, esp the cheaper ones will not a have a uniform shape. You can bet on the header port being larger than your head port so as long as the gasket isnt significantly smaller than the head, you will have no issues

Use the high temp RTV or get used to changing gaskets

Just to inform you, they sell Percy's Deadsoft gaskets at auto zone.

I was aware they carried Percy's Deadsoft gaskets at autozone. That was the backup plan in case they didn't have manifold gaskets. Since there seems to be some confusion, what I'm used to referring to as 'manifold gaskets' are nearly solid metal gaskets with a separate piece for each port (3 separate pieces per side) rather than the continuous (one per side) 'header gaskets'. I was able to find them in square port, but not in round port.
It turns out that my old gaskets were too big (part of why they never did seal right I suspect). The headers appeared to be 1.5" on the inside, and that is the size the Percy's gaskets are. The center holes on the Percy's gaskets looked to be a bit closer together than the header holes, but I'm sure that is the least of my issues with these old 882 heads. I also discovered that while the headers are round, the exhaust ports are oval, taller than they are wide. They really are disappointingly tiny, but that shouldn't surprise me after what I've read about those heads.
I was unable to get the gasket in place with an end bolt with lock washer started so I put the end bolt on without a lock washer. This proved true for starting the other bolts so I put all the bolts in without lockwashers initially. After tightening them just a bit to crush the aluminum I took them back out one at a time and reinstalled them with lockwashers. I tightened them in steps from the center to the outsides. The only spec I found is 25 ft-lb, and I'm sure I've got them tighter than that. I haven't bolted the y-pipe back on yet, so I'll probably do the other side tomorrow as I already have the gasket. Seeing as I was unsure at the time, I did not use any RTV. The last set which didn't fit at all had no RTV, and managed to last a couple years with the bolts working loose every 8 months or so, so I didn't think the aluminum ones would need it.
To others who have the same issue I did getting the header out (or in for the first time) I did manage to get the header out. I had to rock it forwards so the flange was pushed up to the back of the ac compressor/smog pump delete pulley(I think) and then pull it out rear first. I was ableto do this without removing the taller than stock valve covers, although I did remove the two rods that hold it down on the exhaust side of the valve cover. Hopefully tomorrow I'll get the rest of it done and then I can report in saying that my car is a bit quieter.

The last interesting thing is that one of the fusible links on the + terminal of the starter was completely burned out. I went ahead and replaced it, but I don't remember anything in my electrical system not working. Does anyone know which wiring diagram I would need to look at to see the things coming off of that port? It isn't the one to the starter because my car still charges. If it helps, it was purple, and fed two of the large red wires.

Post pics pl0x =]
Everyone enjoys seeing them and visualization might help your descriptions. =P

I keep leaving my camera in my girlfriend's car, so I haven't taken any pictures yet. I'm still not 100% convinced that the Percy's gaskets are sealing because I've got a ticking coming out from every cylinder. It sounds like a rocker arm tick, but I can't see how every single rocker would start ticking (oil level and pressure is fine).
As for the mysterious fusible link, I'm still not 100% sure what it goes to, but I get a ding when I have my door open, keys out of the ignition, and forget to turn off my headlights. It didn't do that before. Also, the voltage in the car is MUCH more stable. Before the fans would drag the voltage down on their own. If I turned on everything (radio, lights, wipers, blower, radiator fans, defroster, etc) the voltmeter on the dash would dip to nearly 8v (while holding steady at the battery). Now it blips own to 12ish if I'm at idle (~600 rpm) and then pulls back up to 14-15V, and barely moves at all if I'm cruising (~2000 rpm).

I finally grabbed my camera. By this point it seemed like the headers were leaking (and they were torqued down tight more than once). I pulled the passenger's side gasket today and found this. Sorry for the bad pictures, the camera didn't want to focus tonight.

Here are the rest. What now?

The last pic says it all

Either the bolts worked out or your header flange is warped. You can see the good contact along the middle areas but almost no compression near the top/bot

The contact areas look quite rough. How smooth are the header flanges? Alot of times theres a bunch of weld splatted all over them. A quick file job will clean them up

You also didnt put any sealant on there. The purpose of sealant is to fill little gaps to make up for imperfections in the flange or cyl head

I think I may have missed some gasket material on that side because I couldn't get in there very well. It seems it's time to get a little further in and clean it up more. Noted on the warping, it seemed strait when I went at it with a level on the other header, I didn't pull this one though. I had also assumed that the aluminum gaskets wouldn't require sealant, apparently wrong there. I'll try to get in there with some copper RTV. Will some soapy water and a sponge be fine for cleaning the carbon off of these before I apply the RTV and put them back in?

I pulled everything apart this time. I had assumed that since the PS header was flat, and that the DS header looked flat without completely removing it from the car that it was, wrong. I pulled them both out, cleaned them up a bit, and sprayed a few layers of copper rtv on both sides of the casket. We'll see if it works this time.

Those are the only gaskets I dont have problems with. It actualy looks likethere mave have been crud on either the head or the header casuing a sealing issue. as long as you have both surfaces clean those gaskets seal well even with a warped header flange. Ive had them on my car since 05 with no issues. They have been re used on 2 engines.

I have always used stock manifold 3 piece gaskets on shorty headers and have never had a leak or problem. There cheap, seal well, and are readily available. Go with those and crank the headers down and you should be all set. I would never use RTV on exhaust parts either. That stuff is bad news and messy.

Didn't quite do the trick with the spray on copper RTV. It held for about the first 30-40 miles, and then I started to hear that telltale tick. I pulled the driver's side to check it out knowing that I could always put it back on and noticed that the spray on RTV isn't very substantial. I also read the can and discovered that it's only good to 500*F, whereas the tube claims to be good up to 700*F. I went ahead and put a bead around both sides, and put it back on last night. I finished torquing them down this morning and started it up...holding so far. My girlfriend and I swapped cars today (80 miles each way between work and a seminar), so I'll see how it held up tonight, or tomorrow.

I couldn't find 3 piece gaskets that fit, that is what I originally wanted to do. Do you know of a brand/part number for those that is 1.5 inch circle ports rather than the rectangles? I'm not thrilled to be coating my heads in RTV, because you can always see the bead sticking out around the edges. On the other hand, I've had fairly good luck with it (on other vehicles at least), and it's not any harder to remove than a composite gasket that's been baked on.

What are the heads off of? If they are stock heads from the factory engine, you should be able to just look up a set at autozone or something for your make and model car. If they're not stock though, I guess you could try to look up a set of manifold gaskets for whatever they originally came on. As for a part number, I'm not sure off the top of my head....I had just always gotten stock ones for an 86 305 TA since my engine was all original at the time. Good luck though.....exhaust ticks are the WORST noise ever. Makes you feel like your driving an uncle buck car!

The heads are gm casting #333882, from whatever it is those came on. I tried getting gaskets for those vehicles, but they all came up listed as square even though they aren't. Also, the heads are ovals, taller than wide. The headers are larger, and are the 1.5" circle. I'm not sure what heads were that size.

This has been going a while. I hope you get the answer you need. Here's my experience--

• Header flanges-- Some have rough welds that cause leaks. Be sure they're smooth and flat. This and loose bolts are the biggest causes of exhaust leaks.
• Gaskets-- I've tried'em all. The only gaskets that I have found to keep their seal reliably is Fel-Pro Performance header gaskets. The part numbers start with a "Z." One-piece or three-piece doesn't matter. If you're worried about looks, you can trim the outside of the gasket to match the header flange. The ones I use for mine are here: http://www.summitracing.com/parts/FPP-1404/
• Gasket sealer-- Gasket goo of any kind, even the highest-temp RTV, is a waste of money on exhaust. It's just too hot there, especially if you're a performance driver. Aren't we all?
• Oval/Square/Round-- The port shape does not matter at all, so long as the gasket ports don't overlap the heads' ports, and the gasket has good metal contact around the ports. Port matching on exhaust is a lot of work for minimal power gain. Especially when you have oval ports with round header tubes. Here's another advantage to Fel-Pro Performance gaskets. You can get them for any port shape and size.
• Bolts-- Use stainless steel bolts of your choice. Probably the best and easiest to use are bolts with 3/8" 12-point heads. I'm using hex-head bolts, myself. I had to cut a hex key to fit some of them behind the tube bends. But THE KEY to keeping the bolts tight is to run down to your local hardware store and buy old-fashioned split-ring lock washers in stainless steel. I've tried every locking bolt there is, and this is the only way you can get them all in and they stay in place.

Hope this helps.

Well, surely one of you is right. When I RTV'd my y-pipe connection a couple years ago it held until I pulled the headers at the start of this mess. When I did it without, it leaked. Barely, but it did. I'm still not sure about the head to header connection though, as it is much hotter there. There isn't any weld spatter on the headers, but they aren't necessarily all in plane with each other. Hopefully I can just bring them down without having to build them up with weld first. It's frustrating not having easy access to a welder anymore. It'll be Sunday before I get to pulling them again, but I think leveling them is the next order of business.

What I said about header flanges also applies to the outlet flanges, connecting to the Y-pipe. Wherever there is a joint of flat surfaces (header flange to head; collector outlet to Y-pipe), the surfaces MUST be flat and smooth. If they are not, then you can expect leaks. On my headers, there wasn't any welding flash on the surfaces. The pipes themselves actually extended past the surface of the bolt flange! This was on both the head connection and the collector outlets. Some judicious grinding with a hand grinder and checking with a straightedge solved that problem.

Also, I have come to believe through long, hard experience that if you buy any gasket other than Fel-Pro Performance, you're asking for leaks. (No, I have no connection to Fel-Pro.) After proper surface prep, a well-chosen gasket will conform to the surface, filling any little gaps or holes with its own surface material. Copper and aluminum collector gaskets are popular, but they will only work a short while if the mounting surfaces are not perfectly flat and smooth, as they cannot compensate for irregularities in the surfaces.

If you need to use a sealer, then you haven't done proper preparation before assembly. Flat, smooth sealing surfaces, with a proven performance gasket (like Fel-Pro Performance line), will not leak.

if i were to run a gasket at all which i don't i would go with the aluminum or copper type i have always found that gaskets and silicone have a tendency to blow out causeing a bigger leak that one would ever have with no gasket at all just my 2 cents if u don't use any type of gasket, mostlikley u will have some very small unhearable leaks but they will never get any worse as long as the bolts stay tight in my opinion, at least ur elimination one possible problem by not using gaskets at all a higher end header with a thicker flange helps the whole situation also

I'm not sure of the brand of the headers, but they look identical to these:
http://www.summitracing.com/parts/BI...T/?image=large
which look identical to these:
http://www.summitracing.com/parts/SU...5/?image=large

On the note of flatness, are headers supposed to look like this?:
http://www.ultrarev.com/files/images...t_76881_01.jpg
If you look at the first two links, the tubes are not welded to the outer side of the flange. Rather they are welded to the inside, and then ground flat (although apparently not all in plane with each other). They stick around 1/8 inch past the flange on the head side. Do I need to weld them on the tube side of the flange and then grind the other side flat?

Those FlowTech headers are exactly the headers I have on mine.

Yes, they need to look as much as possible like the third picture. On mine, the welds penetrated the flange sufficiently that I only had to grind down the inside. I did not have to weld the outside.

I found that their "premium gaskets" weren't so premium. Fel-Pro Performance gaskets took care of that.

Your results may vary.

I pulled both headers today and started grinding down the 1/8 inch of weld around the flanges...and went right through the welds on at least three of the tubes before getting flush with the flange (pictures to follow). I'll be taking them to my machine shop friend sometime in the next couple days. I'm planning to weld them up on the outside of the flange and then hope they fit on his surface grinder because they will be FLAT when they come off of that. Given their somewhat rusty condition I figure I'll have to sandblast them before I try to weld them.
Now, I have a friend with an oven who's good with paint. Is it worth sandblasting the entire thing, covering them in header paint and having him bake them? They aren't ceramic coated and I'm not that worried about the appearance, so I'm not sure if there's much of a benefit to be had.
If I do that is there anything I need to be worried about? Should I paint the head side of the flange? Also, do I just go to the auto parts store and get whatever header paint they have or should I look for something else (cost?)?
I'm borrowing my girlfriend's car to get to work (63 miles each way) and she doesn't really like riding the bus in that much. For the sake of my relationship I think I'm best off sticking with things that I can buy locally rather than something that's going to take two weeks to show up in the mail. I do not have a paint gun, but my friend with an oven might.
All of the other joints looked good when I took them apart so other than replacing the gaskets AGAIN I think I'll be set after this. Thank you to everyone who has chimed in here. Pictures to follow as soon as I can get them uploaded.

Here are two before pictures.

Here is an after picture. You can clearly see the long arc shaped hairline crack where the tube is no longer connected via weld to the flange. At this point I was done grinding by hand and had started running it over sandpaper to try to hit the high spots. Hopefully tomorrow or the next day I'll be able to stick this thing on a surface grinder post weld repair.

Full size at the link:
http://www.thirdgen.org/techboard/at...s-img_0229.jpg

Those were way worse than mine were. Yes. Absolutely. That's entirely up to you. May help rust on the edges later on.Look for something else. But then, here's a guy who used Dupli-Color "High Heat with Ceramic" header paint. Claims he knows somebody else who used it and after 2 years it still looks good. "I know of a friend of a friend of mine...." Here's the link. http://www.fordmuscle.com/forums/exh...mic-paint.html

The best header paint you can get may be from Tech Line Coatings. Here's a hint: It doesn't come in a rattle can. You need a gun or air brush to apply it. 4 ounces is supposed to cover a pair of shorties. It's claimed to handle 2000 degrees. About 20 bucks for 4 ounces, 50 bucks for 12 ounces. "BHK" is satin black. "ColorGard" is various finishes. They claim no baking needed. Just cure it with exhaust heat. Product page: http://www.techlinecoatings.com/Exhaust.htm
Here's a source to buy: http://www.techlinecoatingswebstore...._Coatings.html

I took them down to my friend's shop and welded them back up. and then ground them down again. Rather than the surface grinder we simply took them to a large belt sander, hopefully they'll hold up. Other than one spot where it's a tiny bit shallow (far enough from a port to not be an issue) they are both completely flat on the back side. A guy I work with has had good luck with some exhaust paint (I think auto store stuff) on some vehicles of his. Seeing as it was available and cheap, and as he wasn't charging for the labor or 3 stage baking (My oven doesn't go to 600*F, and I eat out of it), I went with that. He still has the before paint (after media blasting) pictures, but I'll post the after pics below. However, when I bolted my exhaust back up, I decided to try to avoid the spacer plates (very much a bandaid for something) that I found between my headers and y-pipe. However, I think the y-pipe is now touching the oil pan. I'm assuming that this is a problem, but I figured I would ask your opinion. Picture below.

Interference issue?

After picture: