Header install questions.

[aod]

Still waiting on the headers to get back from the coaters. I got Stage 8 header fasteners for them. I see torque spec for exhaust manifold bolts are 19 ft-lbs. I assume this will still be the case with these fasteners?

[Paul Workman]

Originally Posted by aod

Still waiting on the headers to get back from the coaters. I got Stage 8 header fasteners for them. I see torque spec for exhaust manifold bolts are 19 ft-lbs. I assume this will still be the case with these fasteners?

I don't think you'll go wrong. Being that your running the bolts into aluminum, I think the limitation to 19# is in deference to the head material. For that reason I didn't go with "grade 8s" for my header bolts: just plain ol grade 5s from the hardware store.

I read in the FSM and I noticed that Pete used a bit of high temp (red) RTV on Kevin's headers. I recon a little of the RTV would go a long way - far as the light torque goes, along with a few bolts being obstructed and therefore can't be installed anyway.

P.

[aod]

Originally Posted by Paul Workman

I don't think you'll go wrong. Being that your running the bolts into aluminum, I think the limitation to 19# is in deference to the head material. For that reason I didn't go with "grade 8s" for my header bolts: just plain ol grade 5s from the hardware store.

I read in the FSM and I noticed that Pete used a bit of high temp (red) RTV on Kevin's headers. I recon a little of the RTV would go a long way - far as the light torque goes, along with a few bolts being obstructed and therefore can't be installed anyway.

P.

These aren't grade 8 bolts (well, they may be I'm not sure what grade they are), but they are Stage 8 header fasteners that are meant to be screwed in and then something that looks like a cam lobe is clipped on them so they cannot back out. Here is what they are:
http://www.stage8.com/products_lhb.html

[Paul Workman]

Originally Posted by aod

These aren't grade 8 bolts (well, they may be I'm not sure what grade they are), but they are Stage 8 header fasteners that are meant to be screwed in and then something that looks like a cam lobe is clipped on them so they cannot back out. Here is what they are:
http://www.stage8.com/products_lhb.html

Ah! I've read about them, but never used them. Let us know how you like um. My wife Ami has a SBC in her C3 vert that has long had issues with keeping the friggin header bolts tight. That might be just the ticket. Thanks for the clarification, buddy!

P.

[aod]

Well, I thought I had everything in place for this install. The headers arrived yesterday. I had my mechanic come over and check them out with me. He immediately saw that the flanges were bowed a bit. We put a T-square on the flanges and measured how far they were off (or how much gap there will be when fitted) on each flange. One is .08" off, the other is .04" off. Since these are bolting into aluminum, I can't see any possible way that these thick flanges are going to seat correctly. Is this typical quality for SW headers? If so, I think I'll be getting a full refund and going elsewhere. I'll be calling them later today to see what they say, but I'm not too happy. It's unfortunate, because everything else about them is amazing.

[todesengel]

Honestly it is pretty typical of MOST headers I have dealt with in the past, which is why my intent was to have them milled prior to install

Originally Posted by aod

Well, I thought I had everything in place for this install. The headers arrived yesterday. I had my mechanic come over and check them out with me. He immediately saw that the flanges were bowed a bit. We put a T-square on the flanges and measured how far they were off (or how much gap there will be when fitted) on each flange. One is .08" off, the other is .04" off. Since these are bolting into aluminum, I can't see any possible way that these thick flanges are going to seat correctly. Is this typical quality for SW headers? If so, I think I'll be getting a full refund and going elsewhere. I'll be calling them later today to see what they say, but I'm not too happy. It's unfortunate, because everything else about them is amazing.

[aod]

I just got off the phone with them, they said that since there are 16 bolts that hold each header on, they should flatten out and seal against a gasket or RTV. He said the tolerance for regular small block chevy engines are .060" and that is with 8 bolts holding the header in. I reminded him these are bolting into aluminum and he said that should be fine. I'm a little skeptical, to say the least but I guess we'll see what happens. I'd like to mill the flanges, but there are two issues with that. 1) These have already been ceramic coated and 2) Even if they were not coated they weld the wrong side of flange to mill them down.

[todesengel]

I woudl mill them anyway. Even though they are welded on the flange side, the little amount that needs taken off is not going to corrupt the integrity of the weld. I also believe that as long as the tool was sharp, and you take your time the finish should be ok, but perhaps I am wrong. All I know is that I would not put warped headers on a car. Too much work for too many possible headache, but we all have our own comfort level.

Originally Posted by aod

I just got off the phone with them, they said that since there are 16 bolts that hold each header on, they should flatten out and seal against a gasket or RTV. He said the tolerance for regular small block chevy engines are .060" and that is with 8 bolts holding the header in. I reminded him these are bolting into aluminum and he said that should be fine. I'm a little skeptical, to say the least but I guess we'll see what happens. I'd like to mill the flanges, but there are two issues with that. 1) These have already been ceramic coated and 2) Even if they were not coated they weld the wrong side of flange to mill them down.

[aod]

I guess what angers me then, is with the price I paid for these why didn't they take care of doing that? If I mill them now, I believe I might run the risk of the ceramic chipping off in other places afterwards, correct? Ugh.

[Paul Workman]

Originally Posted by aod

Well, I thought I had everything in place for this install. The headers arrived yesterday. I had my mechanic come over and check them out with me. He immediately saw that the flanges were bowed a bit. We put a T-square on the flanges and measured how far they were off (or how much gap there will be when fitted) on each flange. One is .08" off, the other is .04" off. Since these are bolting into aluminum, I can't see any possible way that these thick flanges are going to seat correctly. Is this typical quality for SW headers? If so, I think I'll be getting a full refund and going elsewhere. I'll be calling them later today to see what they say, but I'm not too happy. It's unfortunate, because everything else about them is amazing.

Hey, buddy!
I just measured mine with a straight edge, and I have .028 and .026 respectively. FWIW, they didn't leak in spite of not having ALL the bolts screwed in (common situation, even from the factory, I'm told), and I used the standard 19ft lb torque on one of Eric's gaskets and no red silicone either.

Hmmm.... 80 tho seems a bit much, but I don't have any other SW headers to reference to. Some SBC header flanges have been at least that far off and more, but I digress...

You might be able to knock off the high spots a little with a long flat file - enough to bring the gap down to .030 (guessing, based on my .028 not being a problem in spite of using no silicone), you might be good.

I don't know that 80 tho is an issue or not easily correctable to an acceptable gap, but I would call SW if you haven't already to discuss it w/ them. Also, Eric sells exhaust gaskets, and his input would be welcome 'bout now. (I wonder if the ceramic coating process resulted in some of the warpage??? Just a thought.)

Bottom line: At this point I wouldn't be too alarmed. You may be able to heat them and re-shape them a little, or like I said, file off just enough to get in the ballpark. But, the fact that the heads are aluminum gives me pause too. If they were cast iron, I know from experience and fussing with headers on SBCs 80 tho is "workable" (with a little filing and good gaskets!).

I too will be interested to hear what others may have to say.

P.