Unfortunately complete aftermarket heads are plagued with lousy valve seal more often than you'd think. That may have been a problem since day one.
Unfortunately complete aftermarket heads are plagued with lousy valve seal more often than you'd think. That may have been a problem since day one.
I would do a compression test and/or leak down test first before condeming the heads and valves. My TPI 350 exhaust pulses are the same at idle.Originally Posted by BLG355
I removed the hollowed cat shell and replaced it with pipe, the truck sounds so much better. But I still have glowing manifolds so it probably didn't to anything for flow, just sound. I did however make a discovery, I'll post a video.
https://www.youtube.com/watch?v=TljX...ature=youtu.be
So, who can guess what this means!, but at the same time I'm relieved because at least now I can fix what is wrong.
BLG
and a vacuum gauge is my favorite fast tool. The old kind. They will show a steady smooth vacuum or if an issue shake....
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
I agree, paper towel tailpipe trick might just be a old wives tail. Leak down tester is a great tool.
89 K1500 Scottsdale 5.7L 5spd 3:42 RamJet cam Dart iron TBI heads 427 PCM swap
95 C2500 Cheyenne 6.5L turbo diesel 4L80e 4:10 DB2-4911 Manual pump conversion 0411 PCM trans control 2Bar COS
05 Outback XT 2.5L turbo gas auto
I'm really starting to hate Dart. This is twice I had bad experiences with them, the first of which I let go as a once and done screw up. Last December I was with TBI Chips as I have stated before, and I had extreme soot from his tune, which he claimed as first was my plugs being wrong. He told me that Dart 165 S/S heads take a .750 reach plug. I know when I assembled the heads, regular .460" plugs fit fine, a little lower than I like, but fine. I've run Vortec Bowtie heads on race motors which actually do take .750 plugs. So, not believing Brian, I called Dart, talked to Ross Clark. He assured me I have the wrong plugs and I need .750 reach plugs, no questions about it. Even after I explained that I have .460 reach plugs and they are pretty much right there, he insisted on them being wrong. I'm just glad these things didn't hit the intake valve, they are so close!
I guess I will be calling them again and sending them some pictures. I have heard they are getting really bad over there, but this is ridiculous.
I pulled the heads, since I did get my emission exemption, I am really doubting even putting these heads back on, maybe I'll go for Vortec heads and a nice intake or something, which is what I wanted to do in the first place but couldn't because of the emissions visual inspection which no longer applies.
BLG
I went with Edelbrock ETec170s and put my vortecs on my boat. Could not be happier.
A picture is worth a thousand words...
I've put engines together countless times, 99% of the time a small chevy. I changed heads, ported heads, did valve jobs, cut spring pockets, pretty much everything I could do without the need of a professional machine shop piece of equipment. I have even used a boring bar and finished honed engines by hand. I am so confident when I put something together because I double and triple check everything, measure and measure again, write it down and double check my double check...except after I assembled these heads and used +.050" locks like I always do(and I've done it so many times, why double check the roller clearance to the valve locks!). So, lesson learned, don't used +.050 locks with self aligning roller rockers.
So, here are two pictures, this sure explains my noisy rockers!
I think we have an answer!
Every valve?
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
Yuppers! I though it seemed weird that these rockers were so noisy, but I had to stop and think about I never heard them with quiet exhaust so I just figured maybe this is normal. With a solid cam and headers you can hear them(expect open headers), but it didn't quiet sound like solid lifters do, but I knew something wasn't right, I just wasn't sure what. My 2002 6.0 is noisy, but it's more of a sewing machine sound, not like this sounded.I think we have an answer!
Every valve?
It's been a little while, with vacations and baseball I let the truck sit a little. I had the heads gone over, got a valve job and cleaned them up, put it all back together, and it seems like they glow easier now than before!
The engine runs so much smoother and is a ton quieter. I'm just not sure why these darn manifolds are glowing. everything else checks out good.
But all is not lost, the exhaust manifolds are going bye-bye. It's time for headers. Only the manifolds are overheating, even the crappy stock Y-pipe isn't getting any hotter than other similar trucks I've checked. So I am going with the assumption that the manifolds just can't move the heat away fast enough?? I guess I will find out soon enough! I am out of things to check, so I think this is the next logical move.
BLG
Well, I installed headers at there is no more glow at low and moderate loads and short WOT bursts. after a hard WOT run up to 90 mph I did get a bit of slight red on them, but it is also lean, dropping into the low 800mv so that could be attributed to that. And to see the red, I am stopping immediately after a WOT pull on a pitch black back road, turning even the lights off on the truck, then I can look in and see a slight glow starting form the elbows off the head and extending maybe a few inches down the pipe. I'm confident now that I can start tuning again with no worries about red manifolds like I had before. Considering before I was putting around town, never going over 2500 rpm and I would have them glowing, and now, I driving it aggressively and there is zero glow.
If anyone is thing about headers and unsure, as I was. I decided to try Hedman Standard Duty headers, they were $425 and very nice overall. They come with a Y-Pipe it was very easy to install. They look identical to the Edelbrock T.E.S. headers from years past. I sand blasted them and sprayed them with VHT coating. I was surprised at the difference the headers made, it was noticeable or sure. I may have had a good 3 hours installed them if you take away the breaks and having to get another beer. The only thing I don't like is the bung for the o2 is very tall, the sensor doesn't reach down as much as it should, so I will fix that but other than that, very nice headers for shorty's and I would recommend them to anyone who wants an easy install.
So finally back to tuning!Thanks again for everybody's input from earlier, it was really appreciated.
BLG
Where is the O2 sensor installed?
I have it in the y-pipe. about 3 inches after the two pipes come together is the bung. The left header has a bung as well right at the collector but the kit comes with a plug so I plugged that one off for now
http://www.jegs.com/i/Hedman/500/69470/10002/-1
That is what I bought. I was going to get the Elite headers with the coating, but then I would have needed to make a y pipe and go through a lot more work for what I was trying to accomplish, which was find out why the manifolds were red.
Have you noticed any low rpm, low map surging, like 1,500 rpm in park? It can happen sometimes with the narrowband O2 in that location due to increased transport delay.
No, but i get surging now while driving at light loads. Oh wait, if I hold the throttle at 1500-2000 rpm it does surge. It's pretty noticeable and annoying, especially while driving. I'm not sure how to figure that one out yet but i'm hoping that just getting the fueling closer will help.
My old o2 sensor was in the same place, it is a 3 wire too. Do you think I should move it to the left header?
BLG
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