Gonna give it a run down and up the hill this morning, will check the plugs as soon as I get back, wonder how much a cheap thermal gun would be worth?

im not sure there is such a thing as a CHEAP thermal gun?

weld Bungs onto cyl 2,4,6, and hook one up at a time to your lap top.... wont look great, but hey if they are getting scrapped once boost comes along, big deal...

There is no design fault, As you would know, you set the length of the runner to tune the harmonic of the runner. the same goes for the plenum, the size and volume of the plenum determins the tuning of the plenum, this is used in the same way as runner length. the plenum is building on what was already there.
the next sep is the pipe leading into the plenum, this too can be tuned.
A good setup will have runner tuned, then have the plenum tunned to help fill in the points where the runner are off, then have the intake pipe tunned to to help again.

then the point of the ITBs is responce. when he opens the throttle the plenum is already at atmospheric pressure, the only air that has to be moved is whats between the throttle plate and the valve. With a single throttle you have to fil the whole plenum with air.

I don't think the sizes of the runner and plenum chamber were an accident or a guess. As I know i gave him some suggested reading on the topic at the start of the thread that would have lead to his setup working so well first time around

so what happens when this becomes forced induction?
the manifold is no longer at atmospheric pressure... and the benfit of ITBs i believe will be lost. The effect of 6 throttle plates could actually hinder the setup when on boost...

When on boost you are relying more on the plenum for distribution, and i dont think this plenum will do it all that well....

Even with boost, the plenum and pipes leading to it are at atmospheric, so the initial response will be the same instant, and as I am going for a GT35/40, I am hoping by the time it would theoretically "run out" of air as such that it would be pushing + pressure anyway.

Distribution wise, possibly not at full throttle, but at part to 3/4 openings, all the plenum has to do is pressurize, as the butterflies will still be controlling the amount of air to each cylinder, unlike a single tb having to distribute the air evenly through the plenum once it's past the butterfly.

Plenum design was a mix of; looking at what's out there (ITB + Turbo) ie: GTR, plus a few track cars, advice from a couple of people who have done it on 4 cyls, available materials etc.

But if it doesn't work with boost, I'll just make another one, possibly one with a centre inlet of some sort.

But as I said, Adelaide doesn't have a 1/4 mile track, so building it based on full throttle openings didn't really appeal. However, if everyone gets their s**t together and we do eventually get a track, then it will be auto, DOT's and big a** tb + turbo time, but until that mythical day comes, I'm looking for something that can happily idle along at 1,000rpm, but tears your arms off as soon as you nail it, and just keeps pulling, linear control on the twisties is also important for me.

the plenum in the engine bay looks beautiful, very much an old school look.... i love it !!

i also like the points being raised, i dont think anyone's "having a go" at you, just having a healthy discussion on a ford modifications forum

some times people comments can all of a sudden switch on a light bulb

And im sure some of our comments (positive or negative) helped the brain juices flow which is half the reason you post this stuff up, for opinions, even if the answer is not totally correct, it makes you sit down, think, and prove it right or wrong...

if all this thread got was well done, well done, good job, good job, no one learns anything.... and no one would be interested.

I cant see how ITBs will hinder boost in any way.. The plenum will still distribute boost as per a single TB except now each cylinder can control how much air it is getting rather than all 6 cyls feeding from one intake. If anything this setup would be one of the best to stop cyl 6 fouling up.... I think under 100% throttle though cyl 6 will be running richer with any front entry plenum.

I have never thought anyone was having a go, I welcome all comments good and bad. I learn best with multiple sources of information and trains of thought.

Forums to me are a research tool as much as a social sharing recreational thing. Ya just gotta know how to sort the good from the bad (one tip for that is take ego out of the equation and just focus on the info being offered).

The support I am asking about is not to support weight, it is to stop vibrations shaking it loose.

Thats a fair point. At this stage it has no turbo and right from the start any of my advice has been from an N/A point of view.

I can see where my advice has and hasn't been taken, I'm sure we all would have done thing a little different.

The best thing about it though, is that it's being done. and it's being done by someone with a standard of work as high as this. More to that is he's not shy of of improving things ar redoing things untill it's right.

At this point the man does deserve a huge pat on the back for job very well done.

Alright, Ive been there, ive done that with turbo plenums..

I WILL bet any one of you guys who are reading this thread... that, this plenum will see a RICH #6 plug..

absolutely, without a doubt, gauranteed, it will have piss poor disribution..

But hey, ignore what I say, go with what your doing, boost it... and eventually what I say will make sense

would that whole issue be solved by having a second intake to the plenum at cyl 4? get all dazfab and merge them together where the plenum starts now?

just putting my opinion regarding individual throttle bodies and boost. The RB26DETT found in Nissan Skyline GT-Rs features individual throttle bodies. (http://www.importjap.com/tags/rb26dett-specifications)

In this picture you can see the plenum on our left. http://en.wikipedia.org/wiki/File:RB26DETT_R34.jpg

Fkn excellent work though mate (to the OP)

No one is doubting you. but at this stage it does not have a turbo and any distribution issue would be so minor that it wouldn't matter.

And just look back through the thread, If and when it gets turbo'd and has an issue like you say, do you think he will leave it or fix it?

Though whole point is it's learning process and at this stage it's all N/A and what he's doing will work for that.