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-   -   Your header pictures. (https://www.rx7club.com/1st-generation-specific-1979-1985-18/your-header-pictures-944176/)

Crispin38 03-02-11 09:01 PM

Your header pictures.
 
Currently building my own header. Wanted see some pictures of others custom headers,
Thanks,

Crispin38 03-04-11 10:48 AM

Guess I'm sticking with my own idea's.. Anyone?

Ken7102 03-04-11 10:51 AM

Custom eh. which materials are you going to use?

xShiFTx 03-04-11 11:16 AM

Why are you building your own? Just because you can?

Do you have some specific design goals?

j9fd3s 03-04-11 12:12 PM

check out dj55b's header and um rx7gto's headers.

https://www.rx7club.com/showpost.php...36&postcount=1

Crispin38 03-04-11 12:36 PM


Originally Posted by Ken7102 (Post 10500096)
Custom eh. which materials are you going to use?

Building a copy of a downing designed header for my Monster Port 12A.
Using regular ol' stainless, and a munch of tubing I have lying around. Won't really matter.
And yeah, I'm building it simply cause I can, I don't care for RB headers, and my exhaust ports are ported so large that they're about 1/4 bigger round than the RB primaries, at least. Running a ported manifold ATM, going with a large primary header now.
Not sure on the primary size, at least 2 1/4".. 3 1/2" collector all the way back to the stock muffler.

Crispin38 03-04-11 05:58 PM

1 Attachment(s)
What i'm attempting to copy.
Also a Downing Design.

flight_of_pain 03-04-11 07:59 PM

Holy short primaries batman!

A ported rx with any sort of overlap is going to want long primaries to do any sort of scavenging. Old school BP and PP race cars typically had ~102" before the collector. Coming straight out of the block before curving has shown impressive gains over the headers that start to curl just out of the flange (this is the problem with the RB header).

Isaac

Crispin38 03-04-11 09:23 PM


Originally Posted by flight_of_pain (Post 10501030)
Holy short primaries batman!

A ported rx with any sort of overlap is going to want long primaries to do any sort of scavenging. Old school BP and PP race cars typically had ~102" before the collector. Coming straight out of the block before curving has shown impressive gains over the headers that start to curl just out of the flange (this is the problem with the RB header).

Isaac

All backwards.
If you think you're right, great. I won't argue.
I'll stick with my 7" inch primaries on my overly overlapped 12A.

flight_of_pain 03-04-11 09:37 PM


Originally Posted by Crispin38 (Post 10501155)
All backwards.
If you think you're right, great. I won't argue.
I'll stick with my 7" inch primaries on my overly overlapped 12A.

Do you have any data to back that up? In my own personal experience primaries that short have resulted a significantly noticeable loss in low/mid range torque. I am running a large SP 4-port 13b, and even the standard RB header worked better than a similar header to what you have there.

Isaac

Crispin38 03-04-11 09:56 PM


Originally Posted by flight_of_pain (Post 10501170)
Do you have any data to back that up? In my own personal experience primaries that short have resulted a significantly noticeable loss in low/mid range torque. I am running a large SP 4-port 13b, and even the standard RB header worked better than a similar header to what you have there.

Isaac

I have no data.
But I have the opposite experience, everytime I go long primaries, I lose sooooooo much low end. With these short primaries, broad power becomes friendly. Keep in mind, these primaries are extremely short, straight as my dick and the collector is also massive. And it stays 3.5" all the way through the muffler.
This specific header was designed by Jim Downing( I shit you not) for a tube chassis car with my Monster Port in it, that tube chassis car now has a 13B PP with another downing designed header with even shorter primaries, but, the length from the collector to the header is much much longer in fact it actually has a U-Bend in it solely to increase length, therefore improving torque.
A while back I and my Grandfather tried building a long primary header with a H-Pipe Balancer in it, and, it did exactly what u describe a short primary system should do.. I just posted pictures of these headers I describe in the 'how much can a rotary take?' Thread in the non tech section..

I've also tried running a RB header on my monster port in my DD and was unpleased with the results so I went back to my heavily ported manifold and open downpipe.
Sorry for the horrible post, I do everything from my phone.
Just stating my experience. I very much lovee this header design inparticular. And really hope I can keep it very similar even though it's going in my unibody car.

flight_of_pain 03-04-11 10:38 PM


Originally Posted by Crispin38 (Post 10501189)
I have no data.
But I have the opposite experience, everytime I go long primaries, I lose sooooooo much low end. With these short primaries, broad power becomes friendly. Keep in mind, these primaries are extremely short, straight as my dick and the collector is also massive. And it stays 3.5" all the way through the muffler.
This specific header was designed by Jim Downing( I shit you not) for a tube chassis car with my Monster Port in it, that tube chassis car now has a 13B PP with another downing designed header with even shorter primaries, but, the length from the collector to the header is much much longer in fact it actually has a U-Bend in it solely to increase length, therefore improving torque.
A while back I and my Grandfather tried building a long primary header with a H-Pipe Balancer in it, and, it did exactly what u describe a short primary system should do.. I just posted pictures of these headers I describe in the 'how much can a rotary take?' Thread in the non tech section..

I've also tried running a RB header on my monster port in my DD and was unpleased with the results so I went back to my heavily ported manifold and open downpipe.
Sorry for the horrible post, I do everything from my phone.
Just stating my experience. I very much lovee this header design inparticular. And really hope I can keep it very similar even though it's going in my unibody car.


That is actually pretty neat, it shows the difference between what two different ports apparently like as far as exhaust tuning.

Isaac

Crispin38 03-05-11 07:00 AM


Originally Posted by flight_of_pain (Post 10501231)
That is actually pretty neat, it shows the difference between what two different ports apparently like as far as exhaust tuning.

Isaac


I'll post my results when I finish this header. I'm afraid I won't be as sucessful because the amount of 'room' I have to work with and I won't be afraid to admit failure if I do fail. But, all in all, it'll be loud. That's the most important part. :nod:

Ken7102 03-05-11 08:51 AM


Originally Posted by Crispin38 (Post 10501488)
I'll post my results when I finish this header. I'm afraid I won't be as sucessful because the amount of 'room' I have to work with and I won't be afraid to admit failure if I do fail. But, all in all, it'll be loud. That's the most important part. :nod:

over here loud = big ticket, but may you have the best of luck, because that would be pretty cool

Adsy01 03-05-11 05:30 PM

4 Attachment(s)
Here's some i used to own.
They were on a frontrunning Improved Production car (IPRA) here in Australia and the car held several lap records while wearing these. The engine was a 13b J-port with quad t/b's.

The're pretty simple in design. keep them straight as long as possible as they come out of the engine, then route the bends so thety are equal legnth.

Crispin38 03-05-11 05:40 PM

Primaries aren't super straight, not like mine anyways, and, they're about mid length. Nice work for sure. :nod:

rxtasy3 03-05-11 07:00 PM


Originally Posted by Ken7102 (Post 10501543)
over here loud = big ticket, but may you have the best of luck, because that would be pretty cool

interesting how cars with loud exhausts get ticketed while harleys continue to get away with it.

DarrenTRS 03-05-11 07:37 PM


Originally Posted by rxtasy3 (Post 10502242)
interesting how cars with loud exhausts get ticketed while harleys continue to get away with it.

"loud pipes save lives" remember...ya can't see em if ya can't hear em :scratch:



seriously...it's ridiculous.
pardon the topic deviation

Crispin38 03-05-11 07:39 PM


Originally Posted by rxtasy3 (Post 10502242)
interesting how cars with loud exhausts get ticketed while harleys continue to get away with it.

It pisses me off,
My dads Buell is loud. Just as loud if not louder than my Late Model Stock car, and it has two three inch dumped collectors unmuffled. I don't understand why they can be so loud and we can't. I honestly enjoy my loud Rex.

Crispin38 03-05-11 07:41 PM


Originally Posted by DarrenTRS (Post 10502295)
"loud pipes save lives" remember...ya can't see em if ya can't hear em :scratch:



seriously...it's ridiculous.
pardon the topic deviation

It's true ya know.

Rotospeed 03-05-11 08:41 PM

http://i725.photobucket.com/albums/w...l/IMG_2338.jpg

a pick of my old RE header.

Crispin38 03-05-11 09:06 PM

Looks pretty similar to RB really,

1badFB 03-05-11 10:02 PM

My cheap and lazy header built from the RB "kit":

http://i64.photobucket.com/albums/h1...7/DSC02805.jpg

Hasnt seen the dyno yet, but paired with a well tuned 48IDA the car feels like a monster :)

Crispin38 03-06-11 07:46 AM

I'll admit I like that. :)
Still going to stick with the short primaries but I the way you kept yours straight starting out is nice. Definetly bet that's beter than the normal Racing Beat design.

j9fd3s 03-06-11 12:09 PM


Originally Posted by Crispin38 (Post 10502844)
I'll admit I like that. :)
Still going to stick with the short primaries but I the way you kept yours straight starting out is nice. Definetly bet that's beter than the normal Racing Beat design.

+1...

step 2 would be to try some different lengths, but geez for something off the shelf its good!


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