Another custom inlet thread!! with a carbon twist!!

[warrenpenalver]

yes another lunatic is looking to make a new inlet!

Now i dont have a Zetec SE engined puma, but i am soon starting to build a Zetec SE for my KA.

What i am doing is to make a large log type plenum to withstand turbo boost. Initially i am going to use the mounting method seen on the LMS inlet, ie mount the plenum chamber to the upper part of the inlet.

That should be fairly simple to do and make.

Secondly i am looking at a compact inlet manifold in carbon. On the KA the engine bay curves down sharply further back than in the puma, so a FRP inlet is too high to clear the bonnet, and a lms style inlet needs the cross member hacked apart.

I will custom route the tubes so i can bring the plenum chamber a bit lower and closer to the engine while just clearing the alternator.

With my work, i already have a mould i can borrow for a massive plenum chamber, so half the work is done. This is what the plenum will look like:

I just need to make a baseplate for it to mount to the inlet and a flange for the throttle body end. This plenum has a 100MM intake so plenty of space for people to fit a bigger throttle body if ever needed.

 

[CherryVimto]

This will be a nice one to keep an eye on!

 

[Wild E. Coyote]

Hm, I am toying with the same idea! Is there anything inside the plenum, or is it just hollow? Are there any air deflectors, turbulators etc? May I trouble for some scetches with dimension lines on it?

Thanks in advance,

 

[warrenpenalver]

The plenum mould has no interior features. I will be putting trumpets on the plenum backplate.

Basic untrimmed dimensions are:
http://www.carbonmods.co.uk/downloads/airbox-ram-air-Dimensions.pdf" onclick="window.open(this.href);return false;

 

[Wild E. Coyote]

Thanks a million. Now, the second and more important question: you will be using it in turbocharged version, ie the pressure in plenum will be above outer.
I am thinking about NA version. If I put it on inlet, the second part is about 22-23 cm long. The total length of inlet manifold is 42-43 cm and that is the length of inlet manifold after the plenum on FRP as well. If I bolt this plenum just to the 22-23 cm tubes behind it, I am affraid I will kill the low end power and driveability?
What do you think?

Thanks in advance,

 

[Kungfugerbil]

What do you think?

Have you seen this page?

http://josephrinek.com/intakemanifold.html" onclick="window.open(this.href);return false;

It's an interesting modelling of flow in a custom intake manifold on an (admittedly turbocharged) engine. It's not definitive or a template, but the design principles are sound.

Another piece I saw a while back was discussing the need for the intake pipes or trumpets to be clear of the walls of the plenum as flow is disrupted and slowed in those areas. You effectively want the trumpets sticking proud of the baseplate and to ensure that there is space at the opposite end of the plenum from the throttle body. The intakes want to draw air from the 'middle' of the plenum body for the best effect. Of course experimentation and modelling is required if you are to obtain the pulse effect to increase the pressure above atmospheric!

Very interesting topic for the curious DIYer

 

[Kungfugerbil]

if I bolt this plenum just to the 22-23 cm tubes behind it, I am affraid I will kill the low end power and driveability?

I thought that the longer the inlet length, the better the low revs performance? As the fast moving air bounces off the closed valve and travels back along the inlet, bounces off the far side of the plenum and back down...so the maximum pressure enhancement occurs at lower engine revs with a longer intake, and higher engine revs with a shorter intake...

It's been a while since I slept so my memory may be wrong!

Of course a fun project would be designing and building a DIY variable length inlet manifold... I don't see why it couldn't be done...

 

[warrenpenalver]

To be fair that design process is all very good for gaining the maximum performance but most designs are limited by other factors.

take the rs200 plenum:

simple inspection of the (badly damaged) inlet shows that the flow will be much more consistant and even.

Space for most front engined cars is the limiting factor, hence large log type plenums are often the best performance solution with the minimal practical compromise.

For my application i will be going for compound boosted.

I may well play with the trumpets a bit, perhaps angled trumpets within the inlet, but im thinking of keeping the basic plenum the same shape.

 

[Sjoerd]

Of course a fun project would be designing and building a DIY variable length inlet manifold... I don't see why it couldn't be done...

Definately on my list. First finish the complete vehicle aerodynamics analysis and the chassis simulation I've been making for the past two years or so. It's nearing near perfection Might start a simple design though for changing subject's sake. I've got a 3D-printer so prototyping should be too big of a hassle too :twisted:

 

[Wild E. Coyote]

if I bolt this plenum just to the 22-23 cm tubes behind it, I am affraid I will kill the low end power and driveability?

I thought that the longer the inlet length, the better the low revs performance? As the fast moving air bounces off the closed valve and travels back along the inlet, bounces off the far side of the plenum and back down...so the maximum pressure enhancement occurs at lower engine revs with a longer intake, and higher engine revs with a shorter intake...

Exactly that is what I said, haven't I? Maybe you missed the first part: on regular puma and FRP the length of intake is 42-43 cms! That is why I am cautios about that! Warren has different situation; he is boosting the engine and the pulsations in intake are not so important; you are forcing the air in anyway. But in NA the resonances within intake and exhaust determine the filling of a cylinder...

 

[Kungfugerbil]

Exactly that is what I said, haven't I?

Sorry, I misread your post. That's the thing with 'race' type plenums - they are all about the higher rev ranges as on a track that's all you will ever experience. Personally on the puma I think the gear ratios and nature of the engine are such that you wouldn't be missing out if you had one fitted - the amount of time in my puma I spend below 3500rpm is extremely limited. Personally I would trade it feeling a little flatter at the bottom end for greater high-rpm shove.

Actually I think the Puma would benefit more from enhanced midrange rather than being stronger at 6000rpm

 

[lightning motorsport]

yes another lunatic is looking to make a new inlet!

Now i dont have a Zetec SE engined puma, but i am soon starting to build a Zetec SE for my KA.

What i am doing is to make a large log type plenum to withstand turbo boost. Initially i am going to use the mounting method seen on the LMS inlet, ie mount the plenum chamber to the upper part of the inlet.

That should be fairly simple to do and make.

Secondly i am looking at a compact inlet manifold in carbon. On the KA the engine bay curves down sharply further back than in the puma, so a FRP inlet is too high to clear the bonnet, and a lms style inlet needs the cross member hacked apart.

I will custom route the tubes so i can bring the plenum chamber a bit lower and closer to the engine while just clearing the alternator.

With my work, i already have a mould i can borrow for a massive plenum chamber, so half the work is done. This is what the plenum will look like:

I just need to make a baseplate for it to mount to the inlet and a flange for the throttle body end. This plenum has a 100MM intake so plenty of space for people to fit a bigger throttle body if ever needed.

LMS180 inlet does not need the cross member hacking apart just so you know fits perfectly in a standard fiesta -puma bay.

 

[warrenpenalver]

Its going in a ka, which certainly does need hacking even for an FRP inlet.

Thats why for testing in someones puma it will just bolt on the upper inlet tract, but for the KA will need a custom inlet to fit in the bay in a sensible position.

 

[Wild E. Coyote]

Just found this… http://www.pumapeople.com/forum/index.php?showtopic=103823&hl=frp%20inlet&st=" onclick="window.open(this.href);return false;

Might be helpful. Does anyone know what happened with that project?

 

[warrenpenalver]

Shame nothing came of it.

My project will be started soon. Thanks to stumc I have the inlet gaskets from which i can template. I also have some 45mm round flexible alloy ducting i can use to mock up the inlet design as i need to fit it in around the alternator yet bring the plenum as close to the engine as possible and as low as possible to take into account the KA bonnet which curves down a lot earlier on a ka compared to a puma. I am also thinking of experimenting with inlet trumpets. Perhaps an angled design with maybe oval trumpets to maximise surface area of the flow captured. I could tweak the angles and hieghts to balance the flow over the four ports.

 

[Milkie]

I've just found out about a the 3D Carbon Fibre Printing Firm...
http://markforged.com/
It may be worth a look, I can't get a quote as I do not have any dimensions for the inlet.

If only we could get our hands on the dimensions of the FRP Inlet or something similar.

 

[warrenpenalver]

You seen the cost?? :evil: makes pre-preg look poverty spec!!

Plus it can only lay its carbon in layers, so there is little interlaminar strength on say a curved complex 3d shape. When laid up in a mould normally, carbon follows the contours in a 3D fashion.

Sure fibre reinforced plastics are still massively stronger than plain plastic but that links 3d printer would only be useful for certain applications.

 

[warrenpenalver]

Finally got my tube to mock up with:

just metal convuluted tube but it can be bent to curves and holds its shape.

Next stage is to make a jig to mount the gaskets so i can mock up the tube shapes for the space ive got.

 

[Sjoerd]

As I mentioned before, let me know the dimensions and I'll see what I can do when it comes to CFD. My company has all the resources available, I guess I can stay late some day and use our CFD stations