Would you grind on these header tubes?

[rang-a-stang]

I spent some decent time ensuring the exhaust ports are matched to the exhaust gaskets. I was not able to port match the header flange though because the header had too much movement relative to the gasket. But now that they have run for a while you can see how terribly they match the exhaust ports! These are probably killing TONS of flow. I guess that's what I get for a set of headers this cheap.

Anyway, would you take a die grinder to these to hog them out a little? I am worried that I will eat through the tube and create leaks. At the same time, some of these exhaust ports are really bad...

[wiley-moeracing]

Put the exhaust gasket up against the headers and take another pic for us. The headers look like the weld bead around the port is not even and missing in some areas? It looks like they are headman or hooker headers?( judging by the welded on plate on the one tube). I would order a new header set rather than grinding on these.

[rocklaurence]

I would check how close the tube/weld is relative to the flange. Then take out the material that will not intrude on the tube/weld. The areas where it is on the weld I would provide a slight taper to blend it in--best you can.

[Ristow]

you're gonna grind right through the tube and the weld trying to match those.



hedman headers dont bother with the dogleg,they just use a flange and tube that nearly fullt matches the square profile of the port.

[rang-a-stang]

They are Hedmans. When I stick my finger in the header ports, none of them have a lip (they feel smooth like they should, they are just not the right shape). If I was a decent welder and had a decent welder I would weld the tube to the outside of the flange and grind the inside. Hm.

If I get a different set, I'll probably have to dump another couple hundred at the exhaust shop getting the Y-Pipe changed to match the next set on top of the actual cost of the headers. Sighhh... this sucks. They are so far off. #8 is the worst. I feel like I need to do something...

Maybe I will send an email to Hedman and see if they will do anything for me...

[rang-a-stang]

I guess Hedman is in Whittier (not far from me). I just sent them a tech inquiry.

[Crankyolman]

I'm pretty sure mine fit the same way. Another thing I ran into was that if I use any brand of gasket other than Headman I get leaks. The right one also comes extremely close to the starter. Since I have access to a TIG welder I have actually considered making my own from scratch but I'm happy with my performance and have a lot of other things going on.

[Full Size Jeeper]

I think the free flow exhaust you have on your rig is more than sufficient for the amount of air you are trying to evacuate out the head. It's not like we are running some crazy compression on these engines. So yes you could probably make it flow more air but we are not making enough horsepower to benefit from it. Also, I have no hard evidence to back up what I just said. If you are not in a hurry to get it back together, give it a shot. I don't think this engine is going to be in your rig much longer anyway. I see a 500 plus!!! horsepower engine in your future!!! I bet you already have a secret fund started!!

[wiley-moeracing]

I would give headman a call and talk to them, my headman's were much better than that and a tiny bit of work made them perfect, I have a set of summit brand and they are better than that on my cj project. I would sell them and get another set. Now you would not realize any real loss running these with a little cleanup since you already have all that work done on the exhaust, is it perfect, no but they will work.

[Ristow]

hooker headers is what i meant to say above. they just use the square port.




hedmans have all been terrible that ive had. 4-5 sets probably.

[bufurd]

On my 65 Olds I spent a week on a set of Headmans porting them to the ports. I brazed a good felet around every tube then opened them up, I was into the braze in a number of places on the tubes. Also the bead around the tube at the flange was some or completely removed so I brazed around all the tubes then rough ground that down then a large flat file to finish sealing surface. A lot of work, this was 26 years ago and I'm still running them. Have right at 30,000 miles on them.

[rang-a-stang]

Hedman said "the ports should be correct" and are sending me a set of their gaskets. Hopefully they get her soon so I can compare.

[threepiece]

[QUOTE=rang-a-stang]If I was a decent welder and had a decent welder I would weld the tube to the outside of the flange and grind the inside. Hm.

If you have the ability to play video games and pay for electric service than you have no excuse.

[rang-a-stang]

If you have the ability to play video games and pay for electric service than you have no excuse.

HAHAHAHAHAHAA!! Fair evaluation! LOL!!!
******************
Hedman gaskets showed up today. Here is what I wrote to their tech:

Ok, Got the gaskets today. Here is what I see (pics attached).

Hedman gaskets match the Hedman header ports well (as we both expected). There are some slight variances here and there, but nothing I would consider unacceptable. So then I compared the Hedman gaskets to the Remflex gaskets. The Remflex gaskets port openings are quite a bit bigger than the Hedman gasket port openings which I believe accounts for the difference between how I port matched my exhaust ports and the header port opening (in other words, it is MY fault the header ports do not match my exhaust ports).

Also for comparison sake, I grabbed my stock exhaust manifolds to see where they lie. It looks like the Hedman gaskets are slightly smaller than the stock manifold ports and the Remflex ports are slightly larger. Since I matched to the slightly larger than stock opening and the Hedman ports are slightly smaller, it makes the difference much more obvious.

My take aways:
a) I super appreciate you sending these gaskets! In my opinion they showed that you guys are putting out a good product. I appreciate you guys assuming the cost of this! I will let the folks on my forums know you guys are awesome!
b) I plan to do a little grinding to the flange to bevel the corners to address the mismatch a little.
c) Next time I do this (there will be a next time) I will make a template of the of the header port, match the exhaust port to the header port, and then make sure the gaskets matches those two.
d) I will probably use the Remflex gasket when I re-install these. They are SOOOoooo thick. These flanges can be super bent and they still seal. I also noticed when I went to re-torque them, they never moved. Remflex calls for 20 foot pounds on installation. I checked the torque after one heating cycle (no change), checked them again after an hour of run time (again, no change), and then again after about a week of driving and no change. They are pretty amazing. Spendy but amazing!

I am OK with all this. Here are some of the pictures I took. I have LOTS more if anyone wants to see them.
Hedman gasket over header ports:

Hedman gasket over Remflex gasket:

Remflex over Hedman:

Stock Manifold port

Hedman gasket over Manifold:

Remflex gasket over stock manifold:

[rang-a-stang]

So with all the recommendations you guys (and the folks on theamcforum) gave and an inventory of my "skills"/tools I decided to bevel any edge that is sticking directly in the flow of exhaust gas and generally try to clean up the port with out getting to the point where I would need to put some chewed bubble gum on there (like I said, I am a horrible welder with a horrible welder). I did not want any 90 degree corners in the port at all but this was as good as I could get. One of the ports (I think it was #8?) was sooo far off, I could not grind it enough without rebuilding the entire flange. Here is that port. Notice the carbon mark goes all the way past the sealing lip. I did not have any exhaust leaks so this is a testament to how AWESOME Remflex gaskets are.

Here are some after pics. Again, they are not perfect but they are better IMHO. None of these are the same port, and I did not take pictures of all the ports. Just a sampling. It looks like I hardly made any changes at all and hardly ground on them at all, but if you go back and look at the original carbon marks, it actually made a pretty significant difference. Looking at the pics, I may spend another hour on them today cleaning a little more.




I will admit, this will almost certainly not make a noticeable difference whatsoever but it is one of those things that would bug me forevvveeerrrr if I knew I did not do anything about it when I could have.