November 15, 2018, 06:41:25 PM

Author Topic: Ronin RX-LS Swap Headers!  (Read 3350 times)

Offline Exidous

Re: Ronin RX-LS Swap Headers!
« Reply #45 on: July 29, 2018, 10:22:13 AM »
How close are the runner lengths? Doesn't look quite equal length from the photo but could just be the angle.

94 BB SBE LS1 Full Mamo top, MS3ProU with TC, RONIN 8.8 and another custom dual 2.5" stainless exhaust. Too loud, need bigger muffler....

Offline frijolee

Re: Ronin RX-LS Swap Headers!
« Reply #46 on: July 29, 2018, 10:59:26 PM »
How close are the runner lengths? Doesn't look quite equal length from the photo but could just be the angle.

They're as close as we could reasonably package but to be honest equal length was only a secondary goal.  To quote David Vizard, equal length is far less important than the right length.  Case in point, perfectly identical equal length "3/4 length" headers just mean that none of the tubes will achieve pulse wave tuning.  In a properly designed long tube header, length is driven by the shock wave at exhaust valve open that heads down the primary at the speed of sound, then when it hits the first major change in cross sectional area the negative reflected pulse wave heads up stream.  You want to time this negative pressure front to occur at valve overlap.  However the math only works perfects for one length, one exhaust temperature, for one ideal RPM.  In practice we see a great deal of benefit over a range of RPMs since the shock wave has some duration to it.

The key point is that, yes equal length is nice to but it's not that big a deal if one runner is ideal at 5800 rpm while the one next to it is ideal at 6500 rpm.  But that would still be a 10% runner length difference.   However, if the shorter tube only comes into play at 8000 rpm, that doesn't work so well for our engines. The RIGHT length, that matters a great deal and that's where we spent our major effort.

Joel
LS2 stroker FC, Mandeville big brakes, widebody, etc
Build thread:  http://www.norotors.com/index.php?topic=1274.0
www.roninspeedworks.com

LargeOrangeFont says: "Joel is right, and I love Joel. But his car sounds like the wrath of God."   ;)

Offline Exidous

Re: Ronin RX-LS Swap Headers!
« Reply #47 on: July 30, 2018, 02:41:42 AM »
Fair enough. If be curious if you could phase match the runners similarly to electrical length of RF cables. Meaning, as long as the length is in whole wavelength steps you get no interference.
94 BB SBE LS1 Full Mamo top, MS3ProU with TC, RONIN 8.8 and another custom dual 2.5" stainless exhaust. Too loud, need bigger muffler....

Offline freeskier7791

Re: Ronin RX-LS Swap Headers!
« Reply #48 on: July 30, 2018, 05:55:09 AM »
Nice job joel.  Always good to see a set of headers with long runners.  Are you gonna dyno test these?

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Offline Track_FC

Re: Ronin RX-LS Swap Headers!
« Reply #49 on: August 22, 2018, 05:51:02 PM »
Any updates on the headers?

Offline DailyDSM

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Re: Ronin RX-LS Swap Headers!
« Reply #50 on: August 23, 2018, 10:49:52 AM »
^What he said.  New engine is going back in my car in the next couple weeks and I've been dragging my feet a bit in order to time it with one of the prototype sets, if they will be available.

Offline Exidous

Re: Ronin RX-LS Swap Headers!
« Reply #51 on: August 28, 2018, 06:41:24 AM »
Seems like most folks are really interested in SS. Personally, I'm more interested in a mild steel(or stainless but $$$) ceramic coated version? I like the corrosion resistance of the SS but ceramic/mild steel seemed to do better with under hood heat and noise. The only downfall is under the car if you scrape off the coating like I did with my JTR's.

Oh and pics please!!!  :secret:
94 BB SBE LS1 Full Mamo top, MS3ProU with TC, RONIN 8.8 and another custom dual 2.5" stainless exhaust. Too loud, need bigger muffler....

Offline 65imp

Re: Ronin RX-LS Swap Headers!
« Reply #52 on: August 30, 2018, 02:40:33 PM »
You guys will get pics when we have some to show.  Our new bender is installed, and we should be situated with appropriate dies for proper bends soon.  We went with slightly thicker Stainless pipe for longevity and reduced noise, but then we needed non-standard dies, and on and on. 
Also Joel has interesting developments, but I will let him share.
absolute power corrupts absolutely  :yay:
93 FD widebody - destroked
69 Suburban - positive manifold pressure
65 Impala - 5.7
59 cad  - WIP
53 spartan - shed status

Offline staticx27

Re: Ronin RX-LS Swap Headers!
« Reply #53 on: August 30, 2018, 04:53:04 PM »
Depending on when these come out, I might even be down to prototype a set too ;)

Offline onefastrx7turbo

Re: Ronin RX-LS Swap Headers!
« Reply #54 on: October 04, 2018, 03:33:50 PM »
If you still need an FC for testing, I'm 100% in, tell me where to send the money!
2015 Nissan Leaf - DD
2006 Lexus GX470 For offroading
1986 RX7 - L92/T56 in progress
Past rides......
I don't really need them listed in my signature................

Offline frijolee

Re: Ronin RX-LS Swap Headers!
« Reply #55 on: October 09, 2018, 11:32:37 PM »
Thanks for your patience y'all.

Like many things sometimes you have to overcome the difficulties before you reach success.

In this case, I know I threw a pretty big wrench in the works with my new job and pending move to an island.   I haven't been able to sit down for a proper work session.  It's also been hard to get time on the bender.  Since setup took longer than they wanted (and they're still fighting heat issues with it) our shop has made a conscious choice to prioritize some easy but lucrative work over finishing up our R&D effort.  We get it, they went balls deep buying this thing and now it needs to make a return as quickly as possible... 

I'm stoked folks are into these but it's going to take some more time before we get there.
LS2 stroker FC, Mandeville big brakes, widebody, etc
Build thread:  http://www.norotors.com/index.php?topic=1274.0
www.roninspeedworks.com

LargeOrangeFont says: "Joel is right, and I love Joel. But his car sounds like the wrath of God."   ;)

Offline onefastrx7turbo

Re: Ronin RX-LS Swap Headers!
« Reply #56 on: October 10, 2018, 12:14:21 PM »
All good, Joel! Life is what happens when you're busy planning things :)
2015 Nissan Leaf - DD
2006 Lexus GX470 For offroading
1986 RX7 - L92/T56 in progress
Past rides......
I don't really need them listed in my signature................