PPE V8 Headers GS, LS, SC
I used new gaskets without silicone though. I'm now getting a code for a leak on the other side (before was passenger). The leak is not that bad though because it takes a long time before the CEL comes on. 95% of the time, the O2 sensor (bank 1 sensor 2) is reading like it should. I really wished they made a recessed seat. Would have made things a lot easier, and it's not even that hard to mill out.
Has anyone tried this? Did it work/fail?
Last edited by LEXO951; Feb 8, 2011 at 08:01 PM.
I'm probably the exception since I didn't use any copper silicone sealant. Then again I was expecting it to be the same as the S&S install where I didn't use any, yet they are still leak-free according to the person I installed it for. I just don't have time to take it out anytime soon.
I'm probably the exception since I didn't use any copper silicone sealant. Then again I was expecting it to be the same as the S&S install where I didn't use any, yet they are still leak-free according to the person I installed it for. I just don't have time to take it out anytime soon.
I must have gone back and forth with retightening the bolts 3 times or so. I'm sure they're on there like they're suppose to. It's a shame there is no seating for the gaskets. It would have made alignment easier, and cleaner. As of right now, there is a gap. The problem is that the cat's flange and the header's flange aren't touching. You allow the gap to change in size and that ultimately opens up room for small leaks. The OEM design is fantastic and it eliminates the need for sealant. Of course we can never expect OEM fitment with aftermarket parts.
Hopefully this is an isolated situation. It is possible that overtightening is making the leak worse. 
It may be a good idea to use copper washers of a slightly smaller thickness than the installed gap created by the lack of recess in the header flange. I saw a box of copper washers of various sizes at Northern (chinese) Tool the other day for about $10 bucks.
It would be great if the flanges had the proper recess which should be slightly less than 1/2 of the factory gasket thickness. This milling is one more step that adds that much more cost to the finished product. I am surprised that this is an issue as I noted the S&S used this exact design and was basically trouble free.
Using gasket material should create a leak proof seal at FIRST but may wear over time with heat cycling and vibration. Again, hard to beat the factory design which isolates the load from the sealing.

It may be a good idea to use copper washers of a slightly smaller thickness than the installed gap created by the lack of recess in the header flange. I saw a box of copper washers of various sizes at Northern (chinese) Tool the other day for about $10 bucks.
It would be great if the flanges had the proper recess which should be slightly less than 1/2 of the factory gasket thickness. This milling is one more step that adds that much more cost to the finished product. I am surprised that this is an issue as I noted the S&S used this exact design and was basically trouble free.
Using gasket material should create a leak proof seal at FIRST but may wear over time with heat cycling and vibration. Again, hard to beat the factory design which isolates the load from the sealing.
We'll see how mine hold up. I'm really hoping and praying i don't get any leaks. I used the original gaskets, which were pretty shot with some copper silicon and i have driver about 300 miles with no problems. I hope JBrady is wrong and the silicon holds because i really don't want to have to take this thing back apart. Like GSteg said, there is a gap between the cat and the headers when you tighten the bolts down. But if i remember correctly it goes away once they are tightened? i'll have to take another look, it was late and i was tired when i got to that part. I just remember having to drill the inner holes on the cats and the bracket to the transmission to make it fit since the headers were about 1" off.
Has anyone else come across this problem also or is this an isolated issue?
I received mine last week and checked them over. NO holes and clean welds.
The fit and finish looked great, my father who has been a fabricator for over 30 years also agreed.
The fit and finish looked great, my father who has been a fabricator for over 30 years also agreed.
With 30 years of fabrication under his belt why not have your father just fabricate you some, for a fraction of what you paid?
Honestly I would have paid a bit more for a recessed seat. I've done milling on these kinds of steel and it doesn't take much effort as long as you're doing it the same time you're cutting out the hole. Kind of a mute point now since the flange is already welded on. Recessing ~1/8" deep is relatively quick and easy. If I decide to keep the headers and I have time, I'll probably attempt to machine the seat, although it may be tough since the metal has already gone through so many heat cycles.

I will have to wait till I move into my house in early march but I defiantly post my experience.
Not yet..its 2 degrees outside and I live in a condo at the moment. 
I will have to wait till I move into my house in early march but I defiantly post my experience.
I thought the same thing till i started doing the research. The main thing is the jig, which PPE bought from S&S. The tooling required to make a set of headers would be in the thousands. I got mine made for me in the GB for around $500, which is a bargain comparing the two. As much as it seems, its not just welding up a couple of tubes.

I will have to wait till I move into my house in early march but I defiantly post my experience.
I thought the same thing till i started doing the research. The main thing is the jig, which PPE bought from S&S. The tooling required to make a set of headers would be in the thousands. I got mine made for me in the GB for around $500, which is a bargain comparing the two. As much as it seems, its not just welding up a couple of tubes.


Oh, Definetly makes sense now. That's why reasearch "ALWAYS" pays off!
I had a cel issue after about 300 miles I was leaning towards changing out my o2 sensors I ran some seafoam through this past weekend and the light hasn't bin on since then dnt see how that would fix that but I'm gonna still change out my sensors and go from there
I thought the same thing till i started doing the research. The main thing is the jig, which PPE bought from S&S. The tooling required to make a set of headers would be in the thousands.
I got mine made for me in the GB for around $500, which is a bargain comparing the two. As much as it seems, its not just welding up a couple of tubes.

While PPE did in fact buy the S&S stuff for the Lexus apps the S&S jigs would be of vitually no use for their current design other than to remove them from use as a potential competing product.
I had actually hoped that PPE would have continued producing the S&S parts but obviously that isn't going to happen.
Machining the flanges to duplicate the factory design would be very desireable. I was a little worried when the S&S did not have that but I can't remember any complaints of gasket failure due to this. Not that it never happened I just didn't hear about it if it did. Machining would be relatively easy BEFORE the header was built on a mill. Machining on the header assembly a bit more difficult but possible. You would want to duplicate the factory depth of the recess and the diameter as the two combine to trap the O-ring gasket(s) in position.







