exhaust manifold design ???

[rburnham11]

Hi there
Quick question. Has anybody built a exhaust manifold that joind the cylinder banks off center creating a uneven manifold. Just wondered because as we all know its the sound of a thumping v8 is the main reason why we buy the chimaera and risk the backlash from the missus, I had a impreza sport years ago and it sounded amazing (rivaled the chim) however when I first got the impreza it had a manifold that joined in the middle and sounded poop, like a angry fiesta, once I changed the manifold for a nice stainless uneven length one it totally transformed the car. Now im wondering what v8 would sound like using a similr approach. Any input on this idea would be great as I plan to build it in the near future....
Thanks
Rich

[fausTVR]

I'm no expert but an asymmetric manifold may actually cancel out the v8 throb we get as standard, if you get what I mean.

[rburnham11]

I get what you mean.... or is it possible it will make it sound like a complete monster. Any more views on this??? Again going back to the subaru's with a asymmetric manifold you could just make out the flat four sound however unequal ones made it burble. Take a look at the impreza sport manifold sure there will be one on ebay. Non turbo ones. Thats what im thinking of but obviously for a v8 design.

[griffdude]

I've got some of CliveF's tuned length manifolds- recent video here-

http://www.youtube.com/watch?v=DmOZJdqb0I4

Quite a different noise. Although still sounds 'burbly' at low revs.

[rburnham11]

Id like to hear that at low revs and just ticking over. Any chance of a couple of pictures of that cliveF manifold please. Still love to see how a asymmetric manifold sounds.
There was a manifold picture posted on here recently that looked interesting, was possibly built by cliveF too actually. Never got to hear how that sounded, have one of you good people got a linky to a video of it?

[NickM450]

Do you mean this one?



A better picture, shamefully stolen from another thread:



Chimaera Video Here

[rburnham11]

Thats the one I meant, is there a YouTube video of this one making some noise. Thats one pretty looking manifold.

[NickM450]

It is very pretty

No YouTube, just the TinyPic video in the link I posted.

[spend]

Clive went to extremes to achieve equal lengths, the aim was to match cylinders to 'blend' the exhaust flow rather than have adjacent ports firing close together in paired primaries...

I'd tend to agree that with the length of primaries in the TVR system equalizing the lengths is probably not too critical (as standard they are not anywhere near equal), other factors are quite sensitive.

[rburnham11]

Unfortunately I haven't been able to play that video yet of this manifold so I havent heard it yet. I assume clive went to these extremes purely with performance in mind which makes sense. Same as the imprezas, equal length makes more for better performance especially when a turbo is involved but its the unequal ones that induce that burble.

[Discopotatoes]

rburnham11 said:

Unfortunately I haven't been able to play that video yet of this manifold so I havent heard it yet. I assume clive went to these extremes purely with performance in mind which makes sense. Same as the imprezas, equal length makes more for better performance especially when a turbo is involved but its the unequal ones that induce that burble.

Which is what were trying to achieve here

[rburnham11]

Unfortunately I haven't been able to play that video yet of this manifold so I havent heard it yet. I assume clive went to these extremes purely with performance in mind which makes sense. Same as the imprezas, equal length makes more for better performance especially when a turbo is involved but its the unequal ones that induce that burble.