Phoenixtb31

Purchased 1 7/8 headers and x pipe from speed engineering on a Monday, delivered to my house in perfect condition on Friday. I have a 2008 LS3 c6 auto. If you're familiar with this setup and this x pipe you'll know the passenger side has to be modified slightly to fit up to the the axle back. It's got a slight bend in it that has to be cut out and a straight piece welded back in, about 3" in length. I took the pipe itself to a muffler shop, along with another stainless steel pipe and the guy completed the modification in about 20mins for $20. My understanding is this will be corrected by the beginning of the year. It's only an issue on the 05-08 c6 so if you have an 09-13 this shouldn't be a concern for you. I've never had my hands on the most popular header brands to compare quality but these struck me as high quality and my friend thought so as well. Welds looked excellent. The clamps didn't get me very excited however so as others have mentioned, I went to Napa and got SS band clamps instead. Btw I asked Sean from speed engineering several questions via this forum and he was very helpful. As far as actual install it took me about 6 hours on a mechanics hoist. I sprayed the manifold bolts with pb blaster for a few days before hand. They came out very easily, I don't know if that's cause of the PB blaster per say but it obviously couldn't of hurt. The spark plugs were actually the biggest pain. Frankly I'm not sure I actually even needed to pull them but I did anyway to replace them. Put anti seize on the plugs and the new provided bolts. In totality I removed the dipstick, plugs and boots, engine covers, negative battery cable to access the manifolds. Passenger manifold I had to disconnect the cat from the manifold to get it out, did the same on driver for ease. Had a friend help me with the manifold extraction and holding up the headers while I bolted them in. As far as fitment I thought it was really good. I had two minor issues. 1. The dipstick bracket was impeded slightly by the header flange when I went to reattach it so I had to use a grinder to shave the bracket down. Again this was a very slight grinding, I probably could of shoe horned it in there but the grinder was 3ft from me so why not. 2. I did find that the length of the system as a whole seemed a little short, you can't just slide the pipes in to their stopping point and move on to the next pipe, I had to go up and down the connections to slide them a little this way or that way to make sure there was no gaps in the slip fittings. For this reason I would say the band clamps were absolutely necessary to avoid exhaust leaks, which I do not have currently. In fairness I did think the welder of my modified pipe cut out a slightly bigger piece then he put back in. But that wouldn't of effected the driver side fitment. But worth noting nonetheless. I have it connected to my 2.5npp and it sounds pretty normal actually until you put it under load, when those valves open up it is an explosion of beautiful sounds lol. For me it's the perfect setup, it's only obnoxious when I want it to be. I'm extremely happy with the purchase and product. At this point in time im very happy I went the speed engineering route. Any questions feel free to reach out.

theandrewo

Thanks for posting so much detail. I'm looking at getting a set of these for my '08 and this was very helpful.

SixAddict

koreanbeefcake

any other pics of the headers? Appreciate you posting a review. I been interested in these.

SixAddict

Phoenixtb31

Yeah I got a Diablo custom tune. One thing I would say is a must, the 24" extensions are too short, it gives you zero play. Get online and buy at least 31"extensions. I almost immediately burnt up both harnesses. They were sitting on the header and literally melted, my fault but you'll struggle to get them in a spot you don't have to worry about with the 24". So I went back and bought 31" extensions, heat resistant tape at Auto zone and a "Hot rod sleeve roll"from Amazon. One other thing I probably would of done is secure up my 02s before install. It's difficult to do afterwards, nearly impossible with the 24" extensions given the lack of play. On the driver side I ran my 02 by the fire wall up over the engine. I liked that I did this cause it's not by the driveshaft and it pulls out further from the header.

SixAddict

Phoenixtb31

My AutoZone didn't have the extensions. I had to search for those online. I don't suspect yours will either.

theandrewo

Really? I've read in several places that 24" 02 extensions are plenty long. We're talking front 02 sensors, NOT rear, right?

Phoenixtb31

Correct, only fronts available for this setup. If the person who said that tied them off before hand, then I guess it's possible he saw an avenue I did not. But even then, there's no way of getting around the exposure to heat so I particulary wouldn't be confident the 02 casing would last very long. Even places that were a couple inches away I could tell were starting to deform. In fairness, I was running very rich before I got my tune which does increase the heat. But I would do 31" cause it gives you options. Possible with 24"? Sure. But I wouldn't advise it

theandrewo

Interesting. Speed Engineering sells 24" extensions specifically for this application on their website. I wonder if others have had this problem after install? Are you able to post any pics of the trouble areas or the way you routed it for those of us that haven't installed yet? (Also, lean mixture runs hotter, rich mixture runs cooler.)

Phoenixtb31

Is that true? Lol thank you. I always thought it was vice versa. I took pics but it's just really difficult to discern the problem areas in the pic, it's so dark. But when I get home I'll show you what I'm talking about with the removed 02s that were away from the headers and the casing still started to fail.

Phoenixtb31

There's also plenty of places people said they were too short...I don't know if there's commonality between these opinions like people who secured 02s after install vs before. I could imagine that possible. But I know on my 08, after install, they were not long enough.

theandrewo

Yup! Lean = less fuel and more air. The fuel has a "cooling" effect on the cylinder, so less fuel = less cooling = hotter.
Some pics would be great!

Phoenixtb31

I'll try to. I've tried five times with my phone pictures of the headers and it won't post. Begs the question how'd I do it for the original post. User error I'm sure smh

Phoenixtb31

SixAddict

Phoenixtb31

I used the provided bolts and applied anti-seize. They are oem bolts so I didn't want to talk myself into something unnecessary. I wouldn't blame you if you went that route, for me I don't have any further plans. Lots of guys go with different bolts for ease of future removal.

HOXXOH

Just for reference, when I installed Z06 manifolds and associated cats/pipes on my '08, I stripped back the tape on the harness and didn't need extensions for the O2 sensors. A few years later when I changed to LG headers, the OEM wiring was still long enough for the sensors. It's because the base OEM harness has the same length wires as the Z06, but they are taped differently to access different sensor locations.
So I'm guessing, you never disturbed the OEM harness, since you had length issues. A couple minutes stripping tape, pulling out the sensor wires, and re-taping may have resolved your problem. It might have also made extensions unnecessary.

Phoenixtb31

I could see that being the case. You're correct, the front 02s I pretty much left their movement limited to the OEM taping.