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Headers for towing

706woodman

Full Member
Joined
May 2, 2009
Messages
196
Location
LaGrange GA
Thinking of putting on some shorty headers to aid while towing and maybe replacing my stock muffler with a flow master.can any of you tell me your experience befor and after you put on headers? Is it worth the money? And did it make big or small difference? And shouldn't they just bolt right up to my stock exhaust? Thanks!
 
I wouldn't recommend Flowmasters unless you're strictly going for sound.  Any data I've seen indicates they actually flow rather inefficiently.  There are much better flowing mufflers on the market.

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As for shorty headers, if you do a search it's been discussed a few times.  I think the general consensus is they don't really do much.
 
Here's some numbers on from the Dyno..

What it doesn't show is that there's a big drop in under hood temps if you go with the ceramic coated which could net a few more ponies and increase the life of under hood components..

 

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Randy said:
Here's some numbers on from the Dyno..

What it doesn't show is that there's a big drop in under hood temps if you go with the ceramic coated which could net a few more ponies and increase the life of under hood components..

Possibly, at least in theory.

Couple notes from that test data.

  • They included "cat back" systems in addition to the headers.  I put that in quotes, since the long tubes actually didn't use cats.  Hard to say how much the headers contributed compared to the other exhaust changes.
  • I'm skeptical on the first data point on the stock test.  Within an RPM is gained 29ft.-lbs.  I'm guessing since that was where they started the pull, that data point might have an error. Too bad there weren't more points below that to really be sure.
  • Doesn't mention any tuning.  (which means it's possible there is even more gains, we don't know).
  • After testing they found the dyno was reading 14% optimistic (just in case anyone is wondering why the stock read so high).
 
The Dyno numbers may have been high but the data should still be accurate as far as a comparison since all were runs were with the same calibration.

The long tubes did have cats you can see them in the picture... And it shows what kind of performance is to be gained with shorty headers vs stock as 706woodman was asking..



Here's the test from FOURWHEELER..

http://www.fourwheeler.com/how-to/engine/129-0910-gibson-short-vs-stainless-long-headers/
 
Thanks for the replies I'm not wanting flow master for sound just was an example really.. I also not much for loud exhaust as I tow  my camper pretty regularly,I'm just trying to add some giddy up down low up to about 3500 rpm. And I do know I will have to deal with some of the sound by opening up the exhaust just don't wanna go crazy with it lol.I see it looks like the long tubes would be best for what I'm wanting to do but I really don't wanna have to hack a bunch of stuff up to get em in the engine bay.the stainless works number looks good!
 
I know it's more expensive then a set of headers and Flowmaster setup but if I wanted to get great performance for towing I would save my money and get a Magnacharger and a Corsa Sport exhaust. There would be the increase in torque and low to mid range power you are looking for and gas mileage wouldn't be hurt. The Corsa would get you increased performance with NO Drone to annoy you or your family.
Several members have installed the Magnacharger specifically for towing and they always rave about the performance gain and quality of the kit.

http://www.magnacharger.com/p-73-suburban-avalanche-tahoe-yukon-48l-53l-2007-2010-magnuson-supercharger.aspx

http://www.corsaperformance.com/viewpart.aspx?year=2007&make=Chevrolet&model=Avalanche&partnum=14246&cfg=259
 
Oh yeah I would love to have one myself! Just can't afford one. Been kicking around the idae of getting me a diesel but really don't wanna part with my avalanche. I have had it bout 8yr and it only has 87k on it. All the diesel trucks I could afford have around 200k on them. That probably is the best solution to get what I'm looking for.
 
Some of the long tube headers actually cost you power down low.  You don't want to get a set with larger primary tubes.

I could tell a difference with my JBA short tube headers.  Nothing great but truck was able to maintain speed on hills better before needing to downshift.

Interesting data on the various mufflers.  I haven't before seen what Bigtrucklover posted.  Maybe I need to ditch my Flowmaster ...
 
Good point enoniam...

For a 5.3L 1-5/8 are probably the best and no larger that 1-3/4 tubes. For the 6.0L/6.2L 1-3/4 on a stock to mild motor, if it's highly modified, stroked or running a supercharger you could probably run 1-7/8 but may lose some low end. But if your making 500-600 horsepower a few ponies down low are not on your list of priorities..

And like said earlier there's a huge drop in under under hood temps and in the real world like when towing that's horsepower, to me any header is a must have and if your budget and state laws allow, go with the long tubes..

Here's a youtube video on header testing.. The motor a modified 427 BBC but the principles are the same.. I wish they would have run it with a set of stock manifolds..

https://www.youtube.com/watch?v=O1bXPNy1Yn4



Edit: Also I had put Flowmasters on first and they rusted out in about 3 years.. I switched to SS Magnaflows, been on for about 5 years still looking and working great with no rust..
 
I currently have Gibson stainless shortys and a flowmaster super 40 on my 09 and I only get a noticeable drone at about 2200 rpm. I also removed the rear resonator. I could tell a difference on hills after i installed em, downshifted earlier and stayed in gear a little longer. A bit better "off the line" but not a huge, break yer neck, kinda change. I am gonna be ordering the OBX longtubes with y pipe and high flow cats on Friday (I think), total cost with shipping is $810. I will be glad to pass on what I see as far as the difference between the two. It will be a week before I can install em after they get here so hopefully you are able to wait that long for results. I'm thinking of finding an open area and using my Bullydog test feature to do some 1/4 mile runs and see if there is any gain, not for the "race factor" but just to see if there is any difference, good or bad.
 
That's great keep us updated on the install and defiantly try to make some runs for a comparison..
 
Headers and y pipe came in...look very well made. The y transition was very well thought through, the welds are good, seen better but seen worse...I'd say about 8 out of 10. Have real cats, not just resonators like the haters say although those are an option. Gonna install this weekend, I'll post how it goes. I would take pictures but I do all from my phone and this site won't allow them, somethin about size and I'm not smarter than my phone.
 
Cheapazz said:
Headers and y pipe came in...look very well made. The y transition was very well thought through, the welds are good, seen better but seen worse...I'd say about 8 out of 10. Have real cats, not just resonators like the haters say although those are an option. Gonna install this weekend, I'll post how it goes. I would take pictures but I do all from my phone and this site won't allow them, somethin about size and I'm not smarter than my phone.

Cool.  I've been considering these. Not a lot of information out there.  Would love to hear details on the install.

I read somewhere that even with it having cats, on one person's swap, it still set a code (maybe not enough reaction taking place?).  I'd be curious yours does.  Also like to know how much of a sound increase.  (Assuming it will be because the cats are probably less restrictive than stock).

Also wondering if you have to buy extensions for the O2 sensors wiring.

Keep us updated!
 
Will do. The system has 1 bung before the cat and 2 after. One is right next to the cat and the other about 6 - 8 inches behind it. I guess I'll see if it sets a code and move the sensors if I need to. Gonna put em in as close to where the stock ones are placed as I can.
If anyone would like pics of em before install just send me yer # and I can text em. Phone still smarter than I am.
 
Bigtrucklover said:
Cool.  I've been considering these. Not a lot of information out there.  Would love to hear details on the install.

I read somewhere that even with it having cats, on one person's swap, it still set a code (maybe not enough reaction taking place?).  I'd be curious yours does.  Also like to know how much of a sound increase.  (Assuming it will be because the cats are probably less restrictive than stock).

Also wondering if you have to buy extensions for the O2 sensors wiring.
Good headers are cake to install. My Kooks went in perfect. ***do have new header bolts and an extractor set at the ready, though.

I have a Kooks catted Y pipe and it popped codes quickly. Just get it tuned. Other than the CEL, you won't get the full effects from them with out it.

Mine again, fit perfect and needed no extensions.
 
Installed the OBX longtubes and Y pipe and pulled the Gibson shorties. Wish i had done the longtubes first, never shorties again. What a difference! Seems like the power is there instantly. The lull I had between 2nd and 3rd is less noticeable and it just powers through it, no downshifting. The acceleration is great and it seems like the truck isn't trying as hard to get there faster, really have to watch the speed now because it creeps up on you.

The sound in the cab is different,  more toward the rear than the shorties. The overall sound is the same till ya mash the gas then it growls to life. Same drone as before, around 2200 up hill, but that is with a flowmaster super 40. I'm sure it would be hardly there with a good cat back exhaust.

Install took about 5 hours, I didn't want to cut my stock Y pipe so I had to drop the transmission crossmember to get it out. With no Y pipe in the way the longtubes slid right in from the bottom easily. No O2 extensions needed although I had to rearrange the right side bundle mount for the rear to reach, no issues though. Had to get 2 bung hole plugs and new header bolts but nothing else.

Took it out for a 20 mile or so test/break in run, no engine light...hope it stays that way. Highway/cruise control driving and side road romping and such, she did well. I would think longtubes would be the best bang for the buck overall. Will do some comparison runs tomorrow to see the before and afters.
 
Thanks for the update... Good to hear you got done with out much trouble.. Long tubes are the way to go if you can..
 
Wow, the was quick.  Appreciate the follow-up.  Great info.  I may have some long tubes in my future.
 
Awesome (y)

Glad to hear all went well. Yes the shorty guys will still argue on but, I'm so glad I did mine. Best bang for the buck. I will still recommend a tune eventually. The handhelds just aren't optimized for much modification. A good shop will find even more.
 
I agree about the tune, unfortunately there are only 2 shops in town. 1 of the places I have a BAD history with one of the owners (involved blood) from before he had the shop and the other is new and unproven, not to mention both want $500 + for 3 pulls without tuning. Need more shops.  (n)
 
Wow. I haven't had mine on a dyno but the last car I did was like $70 for 3 pulls. That was like 5 years ago. My current initial tune was 300 or 350 if I remember.
 
So, I feel I should give a more in depth explanation of the install. Mine is an 09 so there may be some differences from older ones.
I started at the rear of the Y pipe, there's a rounded band over a ball type connection in front of the flex pipe, loosened that and separated. The clamp is help in place on top so don't try to remove it. Then disconnected the O2 sensors, then separated the joints at the shorty heaters. Found out the hard way that the Y pipe doesn't come out so I supported the transfer case and removed the transmission mount nuts, the the 2 right side crossmember bolts then the inside left crossmember bolt and loosened the outer. Small pull and it dropped, pulled out the pipe and re-installed crossmember.
Removed the plugs and wires and removed shorty headers.
Slid left side header up from the bottom and attached with new Mr. Gasket header bolts. Reinstalled plugs and wires. Same for right side.
these headers have the flange welded to them on the end with a short pipe extending past the collector flange, slid the doughnut gasket onto this. The left side header is a few inches shorter than the right, dunno why, just is. The cat, or resonator if thats your choice, is welded with a 90* bend after. There are 3 holes for the O2 sensors,  one before the cat and 2 after. I installed the front sensor and put a plug in the first aft sensor. The first aft sensor is right next to the cat, the second is about 6 inches behind that and that is where I installed my O2 sensor. I put the cat up to the pipe and finger tightened the bolts on the loose flange so it would stay in place but I could move it to line up the slip fit cross pipe.
The right side cat is only the cat welded to the bell fitting with a loose flange, it only has the 2 holes for the O2 sensors (the 3rd is in the Y pipe). Same here, finger tight for fitment with front sensor installed and first aft hole plugged.  The end of the slip fit on the cat is just before the crossmember.
Now for the slip fit of the Y. Slid it above the crossmember into the rear of the right side cat, rotated it so the cross piece going to the left side was below the slip fit for the left cat, lined em up and slid it in. Did a little pushing and pulling and got everything where I wanted it. The cross pipe was hitting the right side aluminum transmission gaurd just a bit so that got bent a touch and out of the way. Once I got it situated where I wanted it and was happy, I tightened the band clamps on the 2 slip fit joints.
The company put in a flanged adapter at the rear of the Y that is at a slight angle to the ball joint on the flex pipe. Finger tightened the 2 flange bolts, aligned and tightened the ball joint and tightened the flange bolts. This is when I installed the rear O2 on the right side. Plugged in all the O2's but the right rear. Because I used the rearmost ports, I had to open the wire holder behind the wheel well and slide the corrugated wire covering down a few inches so the plugs would reach.
Fired her up, checked for leaks, let her idle down for 10 minutes then took her out.
Hope this helps.
I'll do my best to answer any questions about it. Wish I had pics to help but like I said, all on my phone and site won't let me upload em.
 
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