Ugrading The Plenum For A N/a

[useless]

So, are you trying to say that the cylinder furtherest from the throttle body is starved for air?

If so that's number 6 not 1.

I'm no expert and I'm not going to pretend to be one but if a throttle body at one end of a plenum can work for Ferrari, Porsche, Holden, Nissan, Aston Martin etc etc with up to twice as many cylinders I think it can work on a Falcon.

Correct. Number 6 is starved. If Ferrari and co read this post maybe they will change the way they do things. The ideal plenum would run 6 throttle bodies. The standard throttle body is fitted in the middle for good reason.Not perfect but better distribution.

[Adam]

Good idea.

The Grand Prix is on in Melbourne soon. Go and teach those engineers a lesson or two about engine design.

[useless]

Not all cylinders draw air at the same time.

You're making it sound like it's sealed and the only air available is what's in the plenum. Air is replaced as it's drawn in.

The cylinder itself creates the vacuum so the air will be drawn into it regardless of it's position.

The engines vacuum is not from one big hole which creates the vacuum .It is created by six.Each contributes to the amount of volume being drawn in.At the throttle body the six cylinder's vacuum is measured..not one.With the car floored and the throttle body at one end.That end will be benefiting from the total vaccum of six cylinders as opposed to one cylinder right at the end.

The plenum is a sealed unit with air entering one way and having six outlets..the intakle ports..

I might have to go to grand prix ...heheh

Edited 08/03/08 04:20 AM by useless

[senna_T]

but as adam said, each cylinder draws air at different times, so your theory is incorrect, there is always air in the plenum too, its not like the throttle butterfly closes to an air tight seal when you take your foot off the accelerator. If that happened your engine wouldn't idle

[useless]

From memory the sixes firing cycle is in pairs. 1 fires with 4 from memory.Generally when one of the front 3 cylinders fires then one of the back 3 does too. This too would have a simlar effect. I know the throttle body has idle speed controller and the throttle stop screw also holds the butterfly slightly open.

Cylinders do not fire 123456. However the constant induction of each cylinder does coincide with the sequence of the combustion cycle. The cylinders do induct front and back cylinders at the same time. As rpm increases the uneven distirbution would get worse.

[useless]

Im hiring a bus and off to Melbourne we go!!

lol

Edited 08/03/08 04:36 AM by useless

[Airmon]

Im hiring a bus and off to Melbourne we go!!

lol

They're talking Turbo's and you're talking N/A mate, I think you're all on different pages.

And I think someone needs to re-read a few posts, nowhere does it state that an engine blew up and the blame was placed onto the log plenum, useless is just saying that when this was tried on an N/A Motor the power went backwards and the plenum may have been the reason why, he goes on to speculate that the starvation of the latter cylinders may have caused other problems said person experienced. The engine did a few valve springs, didn't exactly 'lunch' itself.

I also don't think that something designed to work on a Turbo motor will necessarily mean it will work on an N/A motor. Nor do I think that the Plenums used on Ferrari are as crude as the ones we are talking about here.