Custom manifold - loooooong runners!
 

I've come across a custom manifold ... Its interesting as it appears to have been made to quite a high standard. It has very long runners and an external wastegate, T25 flange ... well pics are probably more use right now, its just quite a bit different to anything I've seen before, anyone know what it is?

https://www.miataturbo.net/attachmen...ine=1386962204

https://www.miataturbo.net/attachmen...ine=1386962204

https://www.miataturbo.net/attachmen...ine=1386962204

I'd just be intrigued to know if anyone recognises it or knows who made it?

Russell.

WAT


THE


HECK




:laugh:

wow



If that thing lasts more than a few weeks without a crane I'll be impressed

Its apparently been running a standard T25 turbo, about 210bhp at 10psi for just over a year but no details on if its been welded up.

Edit - I'm intrigued why you'd design it like that though. By the sound of things it was made by a specialist exhaust maker, I'm trying to find out who and what material etc.

Russell.

Wow... and no supports whatsoever from what it looks like. Thats insane... im sure it flows like no other... but...... WOW.... hahaha

That is really cool. That length should be good for power, although the collector isn't to great and the cylinders are paired wrong.

I was wondering about a brace, but I guess that could cause problems as well ... its mine if I want it (coming off a car thats being broken) so I might give it a go as I have everything else and all I need to find is a turbo

Russell.

its a t25 flanged turbo. pairing doesn't matter to whoever said that.

Long runners like that will make a lot of power, but your spool will suck more.

I agree that the collector isn't that great.

nice collector.

speed up all those exhaust gasses so they collide with one another more violently

wait

RHD vehicle.

Yep, its in the UK. Made by an exhaust specialist by the sound of things, but can't find any information on where the design came from ...

Russell.

I dont think that the collector is bad at all.

Collectors are FAR more complicated that just minimum angle is best.

Dann

I've seen enough Hentai to know where this is going.

someone link Fae to this so he can bust a nut

Will it work with LHD steering shaft?

Believe the correct answer is: Who cares?

It wasn't a question so much for me as for OP. Might help him sway away from the tempting manifold.

Don't know OPs location though. Might be UK.

In addition to steering shaft, can you imagine what that manifold would do to a LHD brake reservoir?

It wouldnt be that bad if cylinders 1-4 and 2-3 were paired. As it is, its not that great.

No one here knows without looking at a dyno sheet.

Many F1 turbo headers had crazy combined collector angles. This gives greater area inside the collector, which has it's benefits.

Here is the RBR header, with around 90* combined angles.

https://www.miataturbo.net/attachmen...ine=1386983207

A turbo F1 engine with some crazy collector angles.

https://www.miataturbo.net/attachmen...ine=1386983207

Dann

This just in: BPs are F1 motors.

https://www.miataturbo.net/attachmen...ine=1386987137

Go build some manifolds and then come back and talk.

Dann

Sorry, too busy dead-hooking every gear in my 250whp Miata on street tires.

And it has a power curve like this too right? And circuit racing spring rates and camber too?

https://www.miataturbo.net/attachmen...ine=1386990835

Look a back and forth troll does neither of us any good, the point is that not a single person on this forum has or has built or has tested a manifold with the OP design, so none of us can possibly say how it will perform.

Dann

Do you have anything constructive to add to this discussion ?

Look, whatever, again, why the fuck can't MT discuss something that isnt the norm without banging on about how its probably shit over and over with no positive consequences for anyone..

Not the same, but still cool.

https://www.miataturbo.net/attachmen...ine=1386997173
https://www.miataturbo.net/attachmen...ine=1386997173

Other Projects

Yeah but how good of an idea is it to pair cylinders that fire one after another? We're not even talking about the collector on this manifold, we're talking about what happens just before it.

Now that's a much better looking octopus header. Very nice. I kinda don't get his W/A intercooler but that's a different topic

And yet log manifolds are 100% acceptable when running at or below 80% of the flow of the turbo..

I bet this manifold makes more power than the FM or begi ones, and at least as much as the standard absurdflow deisgn.

The runners aren't paired any more of less than any of the following manifolds in practice.

https://www.miataturbo.net/attachmen...ine=1387007406

https://www.miataturbo.net/attachmen...ine=1387007406

Etc,

Dann

People that are running log manifolds know they are leaving power on teh table but they are running logs because they are cheaper. Compare apples to apples dude.. Compare it to absurtflow and begi S4 manifold. Do you see a 4-1 manifold in post 1? Theres just no way a sane person would pay money to have a long runner manifold built thats only as good as a log.

Just to clear up a bit, yes I am in the UK so the manifold will fit on fine. The only reason I'm looking at this manifold is because It's a lot cheaper than any other manifold out there that I can find... the shipping and import tax puts an fm or begi log manifold at about $650 so as I can fit and test this for less than half that (including sourcing a T25 turbo).

As it looks like the results will be interesting I may as well give it a go... so the manifold will be with me in a few days. I'll update with progress and a dyno sheet once its done. Hopefully won't take too long but I'm fitting a new diff and inlet manifold at the same time so don't hold your breath!

Russell.

I am comparing apples to apples, I said it would make more power than the FM and Begi cast manifolds and I said at least as much as the absurdflow one pictured above.

The difference between a log and a tubular setup is 1-2psi of boost at the very most, to achieve the same whp.

And there is NO WAY this is only as good as a log, again I bet that it makes as much or more power than the absurdflow style manifold that is so popular here.

Dann

I get danns points.

the manifold is going to work well... but I think that the collector could have been optimized, but thats another topic. longer runners allow smooth flow... your going to make power.



triple88a, give it up on the cylinder pairing. its not an all motor header... turbo manifolds are pressurized and pairing really doesnt matter. neither does equal length on any kind of standard placement.
think about how subarus have like 4 feet of extra pipe (x2) on the longer runners and changing to equal length only gets like 2hp on an already powerful engine. shit doesnt matter, just get the air into the turbo from the engine smoothly and you will make power.





LOL log manifolds. I have vowed to never build another log since the one i built late this summer. there is nothing good about a log manifold and there is always a way to fit something else in...even with a bmw where space is hella tight. That being said, the only thing that this manifold in the OP posted will loose to any of the other manifolds mentioned here is turbo lag.... long pipes mean more volume to bring up to pressure. not a big deal road racing, but if its a street car you should notice a difference... it will be less than 500rpm though if doing a loaded pull.

Actually they gain around 25hp from going to an equal length well designed header.

U're missing a 0 buddy. Subbies get 20-25 hp from switching from the goofy unequal manifold to an equal one and keeping everything the same. They also get better spool.

Thanks for all the info / discussion guys, I'm learning fast on this ... reading all the pinned threads like crazy so hopefully won't ask too many dumb questions! I'll post again once I have it in my hands, my car is off the road at the moment anyway so I'll pull the old mani off it tomorrow ... thats a cool side effect, my hillclimb car can inherit my Fujitsubo!!

Russell.

If it doesnt have bracing, i would weld a few in, maybe between the space on each tube... just for some extra support. That looks like a crack waiting to happen.

Also, if you are doing it, we want results and all that jazz. Im curious about how it will do. So, keep us informed if you can

He's going to need a crane, not just gussets.

haha... definitely...
Ok... So, steel strut tower brace, with a heavy duty loop welded to the bottom above the manifold...
Then Weld a loop to the top of each runner on the manifold....
Attatch a decent chain from each runner loop, to the loop on the brace.... BAM... problem solved... lmao

That collector kills an otherwise sweet manifold. That manifold is going to perform very similarly to a "flowy log" manifold. With different off boost characteristics and a different location of the torque peak. But should still make the same peak power and torque. The collector is the most important part of the manifold. That thing has a "collector" at best, in essence what they did it take a "flowy log" and make the runners really long.

No, it needs to be braced from below. I have talked to JKav about it and he thinks a brace from below will hold the weight and help with vibration more.

Can someone just dyno it and find out?

Dann

Not that I have a great understanding of engineering, but bracing it from below does seem to make sense. I'll put that to the guy doing the work when he looks at the manifold.

I've put a similar thread on my local forum, and while there isn't the depth of knowledge found on here (I got mostly "oooohhhh" and "aaaaaaaahhh" and "what does that do then"), a few seem to know a bit... one of them has similar thoughts to most of you, and also wants me to get a shift on and dyno it, so he's donated me a "GT28 replica" turbo, it apparently made about 300bhp on his last car (not an MX5) and "its a ball bearing one" ... thats all I know so far but it looks like this will move faster than I'd thought, I just need to get a 38mm wastegate (tial was recommended).

If the post hasn't been too delayed by all the christmas stuff, I may well get the manifold tomorrow... if so I'm taking a drive to C1-r and chucking it straight at Chris (the guy doing the prep work for me) so he can get started!!

Russell.

There's some very blatant differences between those two manifolds and the manifold in question.

I'll let you figure it out.

leave it to dann...

I think it's because it's a piece of shit, and he's gotten so used to defending pieces of shit that he just does it automatically now, whether he has any vested interests in it or not.

sounds about right.

This is an awful piece of shit. I mean... just look how bad it is.

https://www.miataturbo.net/attachmen...ine=1387220237

Manifold arrived this morning so I should be able to do a test fit on friday. We'll use the donated turbo for the mock up and maybe a basic test run but will start looking for something a bit nicer ... so far so good anyway, it looks as well made as the pics suggested and the runners don't look quite as long as I thought they would be. There is a small brace on the inside by the wastegate that wasn't visible from the pictures but it only braces 2 runners. It looks about the right place so possibly replacing it with a bigger one and duplicating it on the other side could work ... as long as the wastegate isn't in the way.

I'll add some pics when I test fit it with the turbo.

Russell

My guess: the turbo will spin and you'll say the manifold is a brilliant success.

Other than possibly some time and money on a dyno, no harm in trying it for the right price, especially if you actually gather some data on it versus just providing subjective feedback.

This.

People saying it'll be rubbish because that's what they percieve it to be doesn't make it true. :vash:

It's similar to the MS devs being adamant the ideal gas law was perfect for air temp corrections.

We all know how true that turned out don't we :brain:

He got it cheap and its a tubular made out of quality materials not soda cans.

I'd give it a shot too.

You are all just mad that you dont have a sick long radius tubular like this.


Okay, so Im trolling, but just let the man dyno it and see, I still think it will perform really well.

Dann

Basically yes, its cheap and its my first go at a turbo, so why not see how it goes. Fingers crossed it'll do ok, but the guy doing the tuning knows his stuff so if its not up to scratch I'll sell the manifold (almost impossible not to make a profit) and go again with something better. Worst case scenario I have to spend extra time and money on more dyno time, but I'm learning as I go so its all worth it I think

Russell.

Oh I'm just being a hater. So long as it doesn't crack, it's a manifold, it works, boost will ensue.