Why Racing Beat Header design?
#1
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Why Racing Beat Header design?
Maybe this has been covered before but here goes. After reading quite a few exhaust threads it seems the consensus is and has been proven that you need 3" after the exhaust port before the bend on your header. Thus bending right after the flange as the RB header does is not a good thing( and seems the main critique of it). I have to think that with RB's rotary experience and history of racing success in the 80's that they know this. Why don't they build their header this way? Is it fitment? Would it not fit in a SA/FB chassis and it just carried over to the FC? Because there is room in the FC to do it.
#2
Old [Sch|F]ool
There are acres of room in an FB engine bay too. If anything the SA/FB may have more room because I am fairly sure the 1st-gen has more engine offset for clearing the RHD steering box, which is more of a space liability than the FC's steering shaft.
The answer is probably that they determined X to be the best overall header length, and designing it that way allowed the headers to fit to the original midpipes. Or ease of manufacture/packaging. Or that at the expected power levels, it really doesn't matter all that much. Or they were expecting to sell worldwide and they wanted the headers to clear RHD vehicles.
Take your pick and you probably won't be too far off.
The answer is probably that they determined X to be the best overall header length, and designing it that way allowed the headers to fit to the original midpipes. Or ease of manufacture/packaging. Or that at the expected power levels, it really doesn't matter all that much. Or they were expecting to sell worldwide and they wanted the headers to clear RHD vehicles.
Take your pick and you probably won't be too far off.
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i would add ease of install to the list, you can RnR the header without taking anything else off, like OEM
not sure about ease of manufacture, it wouldn't be any harder to have a 3" section straight out of the engine, although putting the thing on the car would get interesting
not sure about ease of manufacture, it wouldn't be any harder to have a 3" section straight out of the engine, although putting the thing on the car would get interesting
#4
Old [Sch|F]ool
3" of straight per header is half a foot more tubing, at least two more welds to make and grind smooth... In a production environment, you want to minimize the time sinks and materials costs. Add materials, add labor, add multipliers for expected profits per expenditure, we're talking maybe $40-50 more per header. (If something costs $15 more to make in materials and labor, you don't charge only $15 more at retail! That would be silly and a great way to drive down your profit margins.)
How much did SDJ headers cost, again? How much does Defined get for a set of work-of-art headers? How INEXPENSIVE are Racing Beat headers, in comparison? Expensive headers aren't expensive for the hell of it.
How much did SDJ headers cost, again? How much does Defined get for a set of work-of-art headers? How INEXPENSIVE are Racing Beat headers, in comparison? Expensive headers aren't expensive for the hell of it.
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I think i am the one that sparked this in my thread on the second gen forums. By my math, and i could be wrong, I ended up with a short length of 28.08 with a 6800rpm header design. This seems longer than what a lot of the numbers I have been looking at suggest. I am on a stock port as well and and in the understanding that the header needs to be unequal length unless i read something wrong. If that is correct how to you figure the math for the amount of unequalness(is that a word?)
I am going to build a short style header into an exhaust box with dual mufflers to try and keeps the numbers up but the noise down.
I am going to build a short style header into an exhaust box with dual mufflers to try and keeps the numbers up but the noise down.
#6
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3" of straight per header is half a foot more tubing, at least two more welds to make and grind smooth... In a production environment, you want to minimize the time sinks and materials costs. Add materials, add labor, add multipliers for expected profits per expenditure, we're talking maybe $40-50 more per header. (If something costs $15 more to make in materials and labor, you don't charge only $15 more at retail! That would be silly and a great way to drive down your profit margins.)
How much did SDJ headers cost, again? How much does Defined get for a set of work-of-art headers? How INEXPENSIVE are Racing Beat headers, in comparison? Expensive headers aren't expensive for the hell of it.
How much did SDJ headers cost, again? How much does Defined get for a set of work-of-art headers? How INEXPENSIVE are Racing Beat headers, in comparison? Expensive headers aren't expensive for the hell of it.
i would add ease of install to the list, you can RnR the header without taking anything else off, like OEM
not sure about ease of manufacture, it wouldn't be any harder to have a 3" section straight out of the engine, although putting the thing on the car would get interesting
not sure about ease of manufacture, it wouldn't be any harder to have a 3" section straight out of the engine, although putting the thing on the car would get interesting
#7
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I did a header that had some extra outlet length, made from an RB disassembled kit for Gavin. It made it harder to get the header in and out. Wasn't much, like maybe 1.5" to 2" of straight, but it caused issues with the stock heat shield and possibly the idler arm. I had to trim the heat shield which is not necessary on an RB road race header.
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3" of straight per header is half a foot more tubing, at least two more welds to make and grind smooth... In a production environment, you want to minimize the time sinks and materials costs. Add materials, add labor, add multipliers for expected profits per expenditure, we're talking maybe $40-50 more per header. (If something costs $15 more to make in materials and labor, you don't charge only $15 more at retail! That would be silly and a great way to drive down your profit margins.)
How much did SDJ headers cost, again? How much does Defined get for a set of work-of-art headers? How INEXPENSIVE are Racing Beat headers, in comparison? Expensive headers aren't expensive for the hell of it.
How much did SDJ headers cost, again? How much does Defined get for a set of work-of-art headers? How INEXPENSIVE are Racing Beat headers, in comparison? Expensive headers aren't expensive for the hell of it.
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I think i am the one that sparked this in my thread on the second gen forums. By my math, and i could be wrong, I ended up with a short length of 28.08 with a 6800rpm header design. This seems longer than what a lot of the numbers I have been looking at suggest. I am on a stock port as well and and in the understanding that the header needs to be unequal length unless i read something wrong. If that is correct how to you figure the math for the amount of unequalness(is that a word?)
I am going to build a short style header into an exhaust box with dual mufflers to try and keeps the numbers up but the noise down.
I am going to build a short style header into an exhaust box with dual mufflers to try and keeps the numbers up but the noise down.
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did you read the whole thread? there is a disclaimer at the end where it says its wrong
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that being said, we know empirically that, 28" is in the ballpark, so its not completely wrong.
#17
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I just added 3 feet.
we shall see, I have no dyno and the engine is tired but there is an autoX this Sunday so I will cruise it around a bit and see.
step 1. start over (kind of a common theme recently)
step 2. Add runner length. (approx 3 feet added)
step 3. Add resonator
step 4. add tape?
step 5. stop and compare (while still tacked)
step 6. re-install, inspect for leaks (NONE!)
both headers are RB designed and the street header is absolutely the road race one right before the street header collects you see the slip joint they weld on to the make the change of pipe to the collector, before that they are the same. As stated prior its likely to streamline manufacturing process and cut costs. Like most things.
we shall see, I have no dyno and the engine is tired but there is an autoX this Sunday so I will cruise it around a bit and see.
step 1. start over (kind of a common theme recently)
step 2. Add runner length. (approx 3 feet added)
step 3. Add resonator
step 4. add tape?
step 5. stop and compare (while still tacked)
step 6. re-install, inspect for leaks (NONE!)
both headers are RB designed and the street header is absolutely the road race one right before the street header collects you see the slip joint they weld on to the make the change of pipe to the collector, before that they are the same. As stated prior its likely to streamline manufacturing process and cut costs. Like most things.
#18
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Fidelity101 I'm curious about how that system will work as it is almost the same as a setup I had been curious about awhile back in this thread. https://www.rx7club.com/naturally-as...-dual-1027848/
Only difference is it would've split back into duals. I'm debating on a single similar to your setup now though. Either way from what I've read since I'm ported now I need to collect it somewhere so it's more of a mid-collected vs. collecting around the rear axle now.
Only difference is it would've split back into duals. I'm debating on a single similar to your setup now though. Either way from what I've read since I'm ported now I need to collect it somewhere so it's more of a mid-collected vs. collecting around the rear axle now.
#19
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I wanted the less weight and easier serviceability. I had to quiet my exhaust down per the event coordinators I run with. so I added a resonator but I wanted to remove my rusted *** ancient RB header. So I just did it all at once. if I wanted it to be split it into duals I would not have collected it at all and just bought RB true duals.
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I wanted the less weight and easier serviceability. I had to quiet my exhaust down per the event coordinators I run with. so I added a resonator but I wanted to remove my rusted *** ancient RB header. So I just did it all at once. if I wanted it to be split it into duals I would not have collected it at all and just bought RB true duals.
#22
Coming to a track near u!
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Mine:
https://scontent-b-lga.xx.fbcdn.net/...98&oe=54B52E62
https://scontent-a-lga.xx.fbcdn.net/...fc&oe=54B6F389
Stainless, optimal length, long radiuses out of the flange, dual Borla XR1's...
https://scontent-b-lga.xx.fbcdn.net/...98&oe=54B52E62
https://scontent-a-lga.xx.fbcdn.net/...fc&oe=54B6F389
Stainless, optimal length, long radiuses out of the flange, dual Borla XR1's...
Last edited by RacerJason; 10-17-14 at 09:34 PM.
#23
I'm finally at the stage of building the exhaust system on my PP engine and still unsure to go with short or long system. I'm running a rx8 box so I'll have quite a drop in revs with each gear change. So will need good power form 7000 to 9000rpm. Is a long system good for good mid to top and short just for peak hp? Any help guys would be great.
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Mine:
https://scontent-a-lga.xx.fbcdn.net/...fc&oe=54B6F389
Stainless, optimal length, long radiuses out of the flange, dual Borla XR1's...
https://scontent-a-lga.xx.fbcdn.net/...fc&oe=54B6F389
Stainless, optimal length, long radiuses out of the flange, dual Borla XR1's...
#25
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I'm finally at the stage of building the exhaust system on my PP engine and still unsure to go with short or long system. I'm running a rx8 box so I'll have quite a drop in revs with each gear change. So will need good power form 7000 to 9000rpm. Is a long system good for good mid to top and short just for peak hp? Any help guys would be great.
i want to buy 3, 4 foot sections of pipe, and cut one in half. this gives me the header 32", header + 2 feet, ~50", header + 4 feet, ~70", and then header +2 foot + 4 foot, which is 90"
that's 4 runs on the dyno...
once you get to the approximate length you can fine tune it a little.
i'm hoping mine wants a shorter header, so i can run more muffler, but i guess we'll see