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Hi
Our new Fiesta High Flow Inlet hoses will be in the USA in about a week. These are produced from high quality UK silicone and feature stainless steel wire reinforced areas to prevent deformation under engine load. We've seen a nice improvement in air flow , over 35% . These are the perfect foundation for further upgrades and complement our Fiesta Induction kit. Fiestast.net members can use coupon B299hose for 10% off for the next 30 days (ends Feb 28 2014). Thanks

More information here.


b299st_ind.jpg
 

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Sweet I'm order 74, same year as I was born.
 

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I sent Ken an email about a blue hose, he said they will available in a few weeks. So he's going to hold my order till blue comes in. I think the blue hose will go nicely with my PB FiST.


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Should utilize some more colors from the ST line-up :troll:
 

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Hi
Our new Fiesta High Flow Inlet hoses will be in the USA in about a week. These are produced from high quality UK silicone and feature stainless steel wire reinforced areas to prevent deformation under engine load. We've seen a nice improvement in air flow , over 35% . These are the perfect foundation for further upgrades and complement our Fiesta Induction kit. Fiestast.net members can use coupon B299hose for 10% off for the next 30 days (ends Feb 28 2014). Thanks

More information here.


View attachment 613
Hi Ken;
Can one expect any gains using this hose with the soon-to-arrive :D MP215 kit ?
Thanks in advance :)
 

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I am guessing they'll certainly be complimentary to each other.. But I would think the gains from each would be the same whether individually or paired. I don't think putting them together would make one or the other "significantly" more potent than they are on their own. Correct me if I am wrong.

I am... curious to see what exactly this 35% is calculated based on?...How is this impacting PSI, torque/HP #'s, pull @ both low end and high. 35% more air in there sounds like it should actually be providing pretty ridiculous gains for just a tube in a turbo unless I am misunderstanding something..... I didn't think gains that significant were common place for an inlet tube replacement. 35% seems massive.

Shouldn't that produce at least half to all of what the whole mp215 kit is producing in power gains?

Any knocking? Or need to step up in fuel grade? Better off adding a tube after other upgrades? Or is it fine as a standalone upgrade too?

Feel free to school me here, I am not being a smartass. I would like to hear more about how this 35% translates into real world gains. And what the result of such a seemingly significant gain is.
 
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A flow bench measures air flow at a pressure differential.

Typically an engine has "manifold vacuum" created by the piston traveling down the bore while the intake valve is open, sucking in air. A turbocharged engine is similar but the spinning compressor creates a vacuum at its inlet even when it is pressurizing the intake at the compressor outlet.

The thing to understand is that in an engine, air flow is pretty much constant if rpm and load are held steady while a flow bench is designed to hold pressure steady across a variable restriction.

Air flow and pressure are proportional when the velocity is much lower than the speed of sound.

If your engine is not pumping 500 cfm, the vacuum at the compressor inlet is going to be lower than the vacuum they were using on the flow bench.

Long story short, the pressure differential across the pipe will never be very high but if you can reduce it, you might be able to get more boost out of the compressor by a similar amount. It will be fractions of 1 psi, not 35% more air flow or 35% more boost.

Every little bit helps but this one is just a little bit.

If you did something like a turbo upgrade and the peak flow increased greatly, it might become a bigger deal.

I'll probably get one but I'm not expecting much change, especially when I have no way to tune for it.
 

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wash, if I understand your post correctly--thanks for it, by the way--this is my reading of how the bench testing corresponds to real world:

The bench test used a vacuum system to establish a delta pressure through the hose that yielded, at constant delta pressure, a constant flow rate. Given the same delta pressure when testing both the OEM hose and the mountune hose, the mountune hose achieved 35% greater air flow. BUT, this doesn't translate directly or particularly well to the real-world system. The actual vacuum achieved by the turbo and thus the delta pressure achieved during engine operation is much lower than the vacuum and resulting delta pressure applied in the bench test, and since, as you point out, pressure and flow are proportional at speeds well under the speed of sound, a small change in delta pressure as seen in the engine system will result in an equally proportionally small change in flow.
 

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Pretty much.

To put it another way, the theoretical maximum airflow through an engine (neglecting ram effect) is this:

(Rpm/2)*displacement*((manifold pressure + 1 atmosphere)/1 atmosphere)

The Rpm/2 is because its a 4 stroke engine and when I say manifold pressure, its gauge pressure not absolute.

In the real world, there is restriction. In a naturally aspirated engine that means the pressure inside the cylinder is lower than at the air filter. In a turbocharged engine, that means there is less pressure inside the cylinder than at the compressor outlet and less pressure at the compressor inlet than at the air filter.

Reducing restriction decreases the delta pressures and increases flow but a good modern engine like ours already is well in to the area of diminishing returns unless the design is restricting flow purposely.

Lastly, if the waste gate is being actuated at all, there may not be any increase in air flow, just slightly lower exhaust back pressure which is still good but not as sexy as increased flow.
 

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So, to really simplify: The tube is capable of 35% more airflow, but we don't need/can't use all that increase. Not saying it doesn't improve things, just not a full 35% increase on our engine.
 

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If you simplify it that much you could get very cynical over a "35% increase" rather than understand what that flow bench testing means to you.
 

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Your statement is kind of like the flow bench result, absolutely true in one single condition.

Change a condition and the conclusion can change.

Its tempting to grab an absolute and stop thinking about things but reality is hardly ever black and white.

Our engine surely will respond to the hose in almost every operating condition but the effect won't be 35% more power which is what would happen if we were burning 35% more air/fuel mix.

That doesn't mean flow bench testing is bogus, its a tool that allows us to compare things under artificial controlled conditions. We just have to remember that real operational conditions are different so flow bench results need a little interpretation.
 

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OK, I never said it was bogus and I never said it wouldn't help our cars. I purchased a similar one, so I agree with the principle and I do notice a difference. I was just trying to make it clear that a 35% increase in TUBE capacity does not translate to a 35% increase in overall performance. I think we're saying the same thing, I'm just saying it in a manner that helps prevent people from buying it and then complaining that their car isn't 35% faster.
 

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Thanks, wash. Appreciated. And Scott, I think you were simply trying to boil things down to a simple statement of a reasonable conclusion based on the discussion, and I think you were basically correct, as I understand things. I suspect wash knows quite a bit more about this sort of thing than I do or ever will, and thus he can see how we--or at least I--are/am perhaps not quite correct on some things, and sometimes it's hard to let such things go. But wash, if I'm wrong on this, I apologize.
 

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I may be beating Ken to the punch here. But here are the colors for the hoses. Apparently on back order in the UK but they are throwing in a wipe and a keychain for new orders too... Not sure if that's UK only.
 
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