Header/Exhaust System Design
- Thread starter DEFIANT 7M
- Start date
No, they're not. 1, 2, and 3 are on one collector, and 4, 5, and 6 are on a separate collector.
The header needs a little modifying to make it fit right, but not a big deal. I had mine fit in an hour or so. That includes changing all the studs, but none of mine stripped. Before you install it, you need to cut off and cover the little o2 sensor thing on the end, and install a universal one right behind the "Y" pipe. Then you can use any universal one wire 0-2 sensor, or a wide band. Also, have the "Y" welded to the collectors in the proper position. The supplied clamps won't hold it together. Ask me how I know...
The header needs a little modifying to make it fit right, but not a big deal. I had mine fit in an hour or so. That includes changing all the studs, but none of mine stripped. Before you install it, you need to cut off and cover the little o2 sensor thing on the end, and install a universal one right behind the "Y" pipe. Then you can use any universal one wire 0-2 sensor, or a wide band. Also, have the "Y" welded to the collectors in the proper position. The supplied clamps won't hold it together. Ask me how I know...
I have a question. I've been following this thread and I read about the pule firing pattern earlier and it seemed to make sense to me, odd cylinders go in one cycle and even in another. It just occured to me though, why does it matter that the cylinder fired at the same time lead to the same collector. As it is headers they are setup 1-3 in the first collector and 4-6 in the second, but what would be the difference if they are groupped 1/3/5 and 2/4/6 into the first and second collector, respectively.
I understand on the first cycle, 1, 3, and 5 will flow together into the first collector and through the exhaust, and the second cycle will also group the exhaust and send it through ghr second collector to be expelled. It seems that even it the headers were left as they are, two collectors would vent the gases through the exhaust, no different destination, as opposed to one at a time. One collector will have gases coming from one primary and the other will be from two primaries but both collectors join and head to the same place.
I truly don't understand, so I'd rather ask than shrug it off or hope for an answer to pop. I realise I might be missing something and due to the night I had, I'm definitely not at my sharpest, but I'm not high, hungover, or a complete moron....imo
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The only application I can think of an answer for this is a turbo car, since they exhaust gases are re-circulated then maybe vent one cycle through one collector at a time would give a higher pressure feed to the turbo possibly for a better spool. I've put some thought into it when it hit me and I don't quite understand, can someone enlighten me please?
I understand on the first cycle, 1, 3, and 5 will flow together into the first collector and through the exhaust, and the second cycle will also group the exhaust and send it through ghr second collector to be expelled. It seems that even it the headers were left as they are, two collectors would vent the gases through the exhaust, no different destination, as opposed to one at a time. One collector will have gases coming from one primary and the other will be from two primaries but both collectors join and head to the same place.
I truly don't understand, so I'd rather ask than shrug it off or hope for an answer to pop. I realise I might be missing something and due to the night I had, I'm definitely not at my sharpest, but I'm not high, hungover, or a complete moron....imo
.The only application I can think of an answer for this is a turbo car, since they exhaust gases are re-circulated then maybe vent one cycle through one collector at a time would give a higher pressure feed to the turbo possibly for a better spool. I've put some thought into it when it hit me and I don't quite understand, can someone enlighten me please?
cuel;940746 said:
:bsflag:
...
This is seriously misleading for the readers.
The grouping of cylinders 1,2,3 and 4,5,6 is correct.
The firing order of 1,5,3,6,2,4 produces alternate pulses in each group. A exhaust pulse starting from 1 will reflect at the 2 into 1 collector as a negative pulse and travel back through the first group of 1,2,3 and arrive back at the exhaust port of cylinders 1,2 and 3 at the same time. If it arrives during overlap it will assist scavenging. The length is set so that the pulse coming from 1 arrives at 3 at this time at a certain rpm.
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amichie;941246 said:
It is not correct. When number 1 fires the next cylinder in order is number 5. Not number 2, left alone we have an odd fire in that collector. So number 2 fires in it's current position four cycles later!? To be pulled out of the collector by what cylinder? Number 4 in another collector connected by a Y pipe downstream getting a weak exhaust pules? Tell me how that is right. The Tri-mill is a 6 into 1 header, but at the collector the primaries are group just as I'm saying 1 next to 5 next to 3 next to 6 next to 2 next to 4. Just like a revolver.
My question to you is..What's up with the :bsflag:
I'm spending money and time to try this not you!! Pull the flag on someone that is not worth a shit not me.
I think AJ was asking if they were in the order that Allen has determined(1,3, and 5 in one collector, 2,4, and 6 in the other), a page or 2 back, to which my answer is correct.
Thanks Allen
Thanks Allen
Yeah I think that was all mis-understood. I asked cuel if the OBX was in the correct order I couldn't tell from the pic.cuel;941636 said:I think AJ was asking if they were in the order that Allen has determined(1,3, and 5 in one collector, 2,4, and 6 in the other), a page or 2 back, to which my answer is correct.
Thanks Allen
Straight from Burns Stainless.
"Various exhaust designs have evolved over the years from theory, but the majority are still being built from 'cut & try' experimenting."
"Various exhaust designs have evolved over the years from theory, but the majority are still being built from 'cut & try' experimenting."
AJ'S 88NA;941696 said:Well from the looks of that Pacesetter you're a cuttin' and a tryin'
Yup:biglaugh: But I'm going to scrap this idea, because I am indeed wrong here. The BS flag crap fired me up and I talked to a very good friend of mine, who has built countless cars. He said what is the proverbial best inline six out there? That was easy BMW E36 in an M3 my nemesis. He proceeded to ground me even further. By asking me the firing order, it is 153624.So I said:3d_frown:
Well a picture is worth a thousand words. This is a Supersprint header, http://www.europeancarweb.com/projectcars/0201ec_bmw_m3_cams_headers_pulleys/photo_10.html
This thread has some good information in it. I still believe we can make more hp/tq with an improved designed header. He also killed my 6 into 1 dream for "Mythical". It's a hard pill to swallow when your wrong. But wrong is wrong. I stand in front of my peers corrected!
Ma70.Ent pm sent. Please delete any misinformation in this thread. Please leave amichie posts and my last post prior to this in-tack.
Thanks
Thanks
AJ'S 88NA;941866 said:
Yea that's what it looks like to me. Plus the exhaust never becomes one pipe. The two pipes only merge at the muffler and that is a dual in and out. I've asked why it's that way. The answer I got was it makes more hp/tq @ a lower rpm range. Making it more usable and enjoyable to drive. Makes sense.. The 6 into 1 looses exhaust velocity @ the collector, it is more suited for all out racing. It's best at high rpms. The 3 into 1 seems to be the best overall design for inline 6 engines.
Ma70.Ent;941868 said:
Okay I'm kool with that.
I know this link is not what you would expect. But trying to make something work that has not been changed in a decade or more is challenging. You just have to think out of the box. The relevance to engines is the same, so stick with me and you will see what I'm seeing.
http://www.rbracing-rsr.com/exhausttech.htm
http://www.rbracing-rsr.com/exhausttech.htm