Engine is out and HP parts ordered, what headers
#1
03-01-2019, 02:01 PM
Engine is out and HP parts ordered, what headers
Upgrading due to noisy lifters,
Decided to upgrade, cam, exhaust, converter, etc...
I've ordered the cam package from GPI Performance, LLT2 VVT cam, 2300 - 2600 converter, now need headers and cats to finish it out. Once I get it all together and back in the truck GPI will tune it.
What is everyone using for headers, prefer ceramic coated but SS may work also. I've looked at the OBX but cannot find any with the cats, the ones for the 6.2l are with resonators no cats, I'm going to call OBX and see if they have anything that will work with cats.
Neal
Decided to upgrade, cam, exhaust, converter, etc...
I've ordered the cam package from GPI Performance, LLT2 VVT cam, 2300 - 2600 converter, now need headers and cats to finish it out. Once I get it all together and back in the truck GPI will tune it.
What is everyone using for headers, prefer ceramic coated but SS may work also. I've looked at the OBX but cannot find any with the cats, the ones for the 6.2l are with resonators no cats, I'm going to call OBX and see if they have anything that will work with cats.
Neal
#2
03-01-2019, 02:41 PM
Some of the top ones I'd consider would be Kooks, Pacesetter, Texas Speed, Gibson, Stainless Works, OBX.... a number of top notch brands out there. OBX is on the lower end but still very good. I put their stainless ones on mine and am happy with them but the cats are as you said, really just resonators. Couple of important points..... do not waste money on shorty headers. Those provide for almost no performance benefit at all. Long tubes is the only way to go.
Ceramic coated will be much cooler under the hood for temps and potentially a little less valvetrain noise but there is a caveat to them. Headers very very often need some "massaging" with a hammer to get them installed. If so the coating will get chipped and they will rust through there and there is nothing you can do to repair the coating if it does get chipped short of totally sandblasting it all of and having them re-coated. They also cannot be welded on without removing all coating where welding is wanted to be done. Stainless on the other hand is also difficult to weld but doable if the same composition filler rod is used and the welder knows what they are doing. One thing many are not aware of with headers is you will hear some valvetrain noise that cast manifolds hide... its not really loud or objectionable but its worth noting.
Ceramic coated will be much cooler under the hood for temps and potentially a little less valvetrain noise but there is a caveat to them. Headers very very often need some "massaging" with a hammer to get them installed. If so the coating will get chipped and they will rust through there and there is nothing you can do to repair the coating if it does get chipped short of totally sandblasting it all of and having them re-coated. They also cannot be welded on without removing all coating where welding is wanted to be done. Stainless on the other hand is also difficult to weld but doable if the same composition filler rod is used and the welder knows what they are doing. One thing many are not aware of with headers is you will hear some valvetrain noise that cast manifolds hide... its not really loud or objectionable but its worth noting.
#3
03-01-2019, 04:07 PM
I did go through your thread on your header install, its what got me looking at the OBX headers. Welding is no issue as I did it for 10 years with a lot of aluminum and SS material.
My concerns with the resonators is I don't really want to delete the 02 codes and don't want to be fighting the MIL due to the 02 sensors, was this an issue when you installed your headers?
I installed some Pacesetter ceramic coated headers on my sons 99 chevy short bed single cab 6.0L we built up and they worked great along with a true dual with X pipe system
No plans for shorties, to me they are a waste of time if your looking for performance,
I'll look and see if they offer anything for the H2,
Neal
My concerns with the resonators is I don't really want to delete the 02 codes and don't want to be fighting the MIL due to the 02 sensors, was this an issue when you installed your headers?
I installed some Pacesetter ceramic coated headers on my sons 99 chevy short bed single cab 6.0L we built up and they worked great along with a true dual with X pipe system
No plans for shorties, to me they are a waste of time if your looking for performance,
I'll look and see if they offer anything for the H2,
Neal
#4
03-01-2019, 04:17 PM
Actually I was wrong - the specific OBX set I bought is catted.... That was why I went with that one. At least they say they are.
eBay
https://www.ebay.com/itm/OBX-Performance-Exhaust-Header-99-05-GM-Hummer-H2-GMC-Denali-Silverado-6-0L-/122272027820?_trksid=p2047675.m43663.l10137&nordt= true&rt=nc&orig_cvip=true
That being said - I have had a code popup a few times but it then goes back off on its own. I think it might be due to some leaks on the clamps which I know I have. I just have not had time to jack it up and re-tighten everything but I've also been thinking on getting some of the better high end clamps and also putting some exhaust sealer paste in the joints when I do. I've also been skeptical that the cats are doing much though regardless - if the H2 is running you pretty much cannot stand behind it - you will choke on the fumes. I do run premium and have a custom tune which is a little rich at idle though - those also add to the fumes.
Edit to add - with the engine your are going to have... you will need to run a custom tune as well. So really you can just tell them to remove the O2 codes out of the tune so you will not ever have a check engine light for that.
eBay
https://www.ebay.com/itm/OBX-Performance-Exhaust-Header-99-05-GM-Hummer-H2-GMC-Denali-Silverado-6-0L-/122272027820?_trksid=p2047675.m43663.l10137&nordt= true&rt=nc&orig_cvip=true
That being said - I have had a code popup a few times but it then goes back off on its own. I think it might be due to some leaks on the clamps which I know I have. I just have not had time to jack it up and re-tighten everything but I've also been thinking on getting some of the better high end clamps and also putting some exhaust sealer paste in the joints when I do. I've also been skeptical that the cats are doing much though regardless - if the H2 is running you pretty much cannot stand behind it - you will choke on the fumes. I do run premium and have a custom tune which is a little rich at idle though - those also add to the fumes.
Edit to add - with the engine your are going to have... you will need to run a custom tune as well. So really you can just tell them to remove the O2 codes out of the tune so you will not ever have a check engine light for that.
Last edited by MixManSC; 03-01-2019 at 04:26 PM.
#7
03-01-2019, 10:06 PM
I am going thru this process right now for my 2008. The only real viable solution I could find was Dynatech SuperMAXX LT headers and catted mid pipes. I haven’t installed them yet and they aren’t cheap (expect to spend around $1600).
#10
03-02-2019, 02:02 PM
I'm not certain about later models but one thing to look for...... a LOT of places will not list certain models simply due to the fact that they have not directly tested them on a certain model. That however does not mean that they will not fit. For example OBX lists the exact same long tube headers set for
2002 thru 2005 Cadillac Escalade 6.0L
1999 thru 2004 Chevrolet Silverado 2500 6.0L
2001 thru 2005 GMC Yukon Denali 6.0L
2003 thru 2005 Hummer H2 6.0L
And you for other brands that say they have one for a 2004 Silverado, for example, they will show the same ones fit some of the same vehicles that OBX shows that theirs will fit on. So there is a good possibility that many others that while they do not specifically state they will fit an H2, it is quite possible and even likely that they will actually fit just fine. What I've sort of determined is that pretty much any one brand of long tube headers for a full size GM truck will just about fit all full size GM trucks and SUV's. Where you might run into issues though would be if the kit includes more than just the headers like the OBX kit which also includes the crossover Y pipe, cats, etc. Now from the cats back, that will be a different story and is a bit more specific to certain vehicles due to the different lengths, frame setups, whether or not they have a transfer case, different trans supports, etc.
One last thing - OBX and a couple of other brands have one bend in the driver side header which I severely dislike. On these, instead of going down like the rest of the pipes and like on other brands, the #3 cylinder pipe first bends up then towards the back and then down behind the #5 pipe. This makes it so that you will need to buy a very short spark plug wire for #5 as it will be touching the header and will burn up. Plus I just think it looks goofy with the one single pipe going up while every other one goes down. Dont get me wrong though, they are a great value choice and if you spend time on many of the GM truck forums you will find that a lot of GM truck owners really do like them a lot for the fairly low price you can get them for.
Another one to potentially check out will be Borla's "closeouts". Borla is the OEM for much of the official GMPP (GM Performance Parts) exhaust. I've seen a number of Hummer stuff on their closeout page over the past couple of years. In fact I got my exhaust tips directly from Borla. They are the only ones with H2 actually stamped into them. I had them on for a while but I took them back off as I do go off road a good bit and did not want to trash them. So I might also be willing to sell those. I also lucked out and spotted a craigslist ad about an hour and a half from me for a still new and unused original GMPP all stainless cat back setup. Turns out the guy owns a Chevy dealership and he used to be a Hummer dealer. He let me have it for just a couple hundred bucks. Crazily cheap for a Borla all stainless cat back setup.
Actually just looked and they have some of the straight flat end tips on there now (mine are the slant cut ones - as far as I know both have a fully rolled lip as well).
https://www.borla.com/products/closeout_corner.html
2002 thru 2005 Cadillac Escalade 6.0L
1999 thru 2004 Chevrolet Silverado 2500 6.0L
2001 thru 2005 GMC Yukon Denali 6.0L
2003 thru 2005 Hummer H2 6.0L
And you for other brands that say they have one for a 2004 Silverado, for example, they will show the same ones fit some of the same vehicles that OBX shows that theirs will fit on. So there is a good possibility that many others that while they do not specifically state they will fit an H2, it is quite possible and even likely that they will actually fit just fine. What I've sort of determined is that pretty much any one brand of long tube headers for a full size GM truck will just about fit all full size GM trucks and SUV's. Where you might run into issues though would be if the kit includes more than just the headers like the OBX kit which also includes the crossover Y pipe, cats, etc. Now from the cats back, that will be a different story and is a bit more specific to certain vehicles due to the different lengths, frame setups, whether or not they have a transfer case, different trans supports, etc.
One last thing - OBX and a couple of other brands have one bend in the driver side header which I severely dislike. On these, instead of going down like the rest of the pipes and like on other brands, the #3 cylinder pipe first bends up then towards the back and then down behind the #5 pipe. This makes it so that you will need to buy a very short spark plug wire for #5 as it will be touching the header and will burn up. Plus I just think it looks goofy with the one single pipe going up while every other one goes down. Dont get me wrong though, they are a great value choice and if you spend time on many of the GM truck forums you will find that a lot of GM truck owners really do like them a lot for the fairly low price you can get them for.
Another one to potentially check out will be Borla's "closeouts". Borla is the OEM for much of the official GMPP (GM Performance Parts) exhaust. I've seen a number of Hummer stuff on their closeout page over the past couple of years. In fact I got my exhaust tips directly from Borla. They are the only ones with H2 actually stamped into them. I had them on for a while but I took them back off as I do go off road a good bit and did not want to trash them. So I might also be willing to sell those. I also lucked out and spotted a craigslist ad about an hour and a half from me for a still new and unused original GMPP all stainless cat back setup. Turns out the guy owns a Chevy dealership and he used to be a Hummer dealer. He let me have it for just a couple hundred bucks. Crazily cheap for a Borla all stainless cat back setup.
Actually just looked and they have some of the straight flat end tips on there now (mine are the slant cut ones - as far as I know both have a fully rolled lip as well).
https://www.borla.com/products/closeout_corner.html