I've heard this before. The stock manifold is only efficient to a certain point. It is very restrictive at high power levels. You could have a winner here Martin should you choose to make some more.

 

Did a bit more with the car yesterday after swapping race fuels.
The C85 is great but using approx 35% more of it meant I couldn't run the nitrous.
I've now swapped to Sunoco MAXNOS fuel mixed with 20% methanol. This gave me the headroom reqd to run the nitrous so in went a 40 shot and this is the result.

 

Got the car to a local drag event ran by Straightliners today.
Ran a new PB of 10.06 @ 165mph although the terminal is a little questionable.
Ecu logged 157mph so I think that's probably closer.
9s are beckoning

 

Them figures are amazing.Is this car still road legal

 

<<<@!1!@>>>

Shy of an MOT but yes essentially it's road legal

https://www.youtube.com/watch?v=LUfo...ature=youtu.be

 

I think the point has already been made but if this weird effort (no offence!) can work so well how inefficient must the OE manifold be? Has anyone actually built a totally redesigned manifold starting with a clean sheet? It looks like a key area for serious power gains.

 

Yes, Cosworth, Tomei, AMS, Magnus have all had a crack at it.
The guys on NASIOC seem to have a lot of love for the NASP manifold too.

Cosworth



Tomei, very interesting as this one used throttle bodies on each port.



AMS



Magnus



NASP manifold



Martyn

 

That's very interesting. In common with your version, although all different shapes, all seem to be creating a 'holding tank' for the charge so that it has a more direct shot into the engine, eliminating the very abrupt and inefficient initial turns of the standard manifold. Was this the thinking behind your experiment? Do these other versions yield similarly good results to yours? It would seem from the pictures that perhaps any 'tank' shape would do the job provided it allowed a straight exit for each port.

Congratulations, I bet your manifold experiment has got a lot of people thinking!

 

Just been checking out this subject on NASIOC, they go into it quite deeply and some of the pictured manifolds earlier get the thumbs down, mostly for poor fit but some for unsatisfactory results. Interestingly it opens up the possibility of twin turbos and all that might entail!