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Discussion Starter · #1 · (Edited)
I'm not a mechanic or an automotive engineer, so please pardon me for asking some questions to help me learn about these products. And thank you for your knowledge and experience.

A cursory check of the interwebs shows modern gasoline fueled engines use 14.7 parts of air to 1 part fuel for combustion. This ratio may be different for any number of reasons, but let's just use this.

#1- Aftermarket air intake systems promise more air actually getting to the turbo unit. Does this also mean an increased volume of air going *through* the turbo in the same amount of time, or just a greater volume available at the intake end of the turbo for the turbo to draw upon? (Comparing the sizes of OEM and aftermarket intake piping, there is no doubt that more air volume is provided up to the turbo.)

#2- If more air per unit of time is actually going through the turbo with the aftermarket air intake systems, would this also mean more fuel needs to be introduced into the air stream as it enters the combustion chamber? (Edit, with claims of better acceleration and increases of power, I'd think more fuel is being delivered to maintain the proper air:fuel ratio.)

#3- Are current users of aftermarket air intake systems noticing changes in your fuel economy numbers (figured manually, using actual miles driven divided by actual gallons used, not via dashboard mpg meters)? If so, what are before/after upgrade mpg figures?

#4- Unless I've missed something in message conversations or mfr. product details, when using aftermarket air intake systems, is re-mapping of the engine's computer required, or at least suggested? (Edit, or is the factory mapping able to compensate for the greater air delivered with added fuel to maintain the proper air:fuel ratio?)

Thanks for your help...
Steve.
 

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Steve I'm no engineer either, and find considering the engine as a pump makes this easier to understand. The engine is between the intake and exhaust and each are a constraint to efficient flow. I installed the EC v4 system and they have data that demonstrates the improvement it makes. If I choose to exploit this improvement (by sticking my foot in it) I'll consume more fuel while enjoying the results. You gotta pay the band if you want to dance. :)
The exhaust has a catalyst, and noise reduction features. Wide open isn't a reasonable alternative anymore. Even pure track cars have some noise limitations. So the sweet spot is being legal, and as loud as you, or your neighbors can tolerate. Our turbocharger eliminates much noise energy, so it makes the "muffler delete" options a viable alternative for some. So you can't forget the "back end" if you want the most out of the "front end".
The ECU is able to manage the improvements we make with these improvements. But, clever engineers have provided "tunes" that re-map the engine performance in varying degrees for different purposes. The serious high-performance ones need the intake and exhaust as unconstrained as possible, but they aren't the best choice for those of us with more leisurely intentions.
I hope this was helpful.
best regards
Pete
 

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I have installed the V1 plus with stock air filter and changed the DV+, I can tell you the car is very responsive and feel the power that I haven't used the sports boost switch yet. one day,Maybe on the highway I'll use it.
 

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1. Yes, more air.

2. Yes.

3. My MPG has gone down because I can't keep my foot out of it.

4. No, the engine computer will adjust for an aftermarket intake.
 
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Discussion Starter · #5 ·
Good, thank you for the replies.

At about 1100pm on a Sunday night, here is what I'm thinking of changing on my Classica once it arrives in a few weeks. (Subject to change after a night of sleep...)
EC V1 intake kit, maybe with their AFE dry air filter.
EC oil catch can.
GFB DV+.
Turbo blanket, probably PTP's blanket which will be available in the coming weeks.
Cravenspeed stubby radio antenna.
And of course one of my homemade wood gear shift knobs!
Any exhaust modifications are pretty low on the list at this time. Actually, not on the list at this time.

Steve.
 

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Hi Steve, I Appreciate this post. Sharky already answered it pretty well, but I'll add a little to it.

I'm not a mechanic or an automotive engineer, so please pardon me for asking some questions to help me learn about these products. And thank you for your knowledge and experience.

A cursory check of the interwebs shows modern gasoline fueled engines use 14.7 parts of air to 1 part fuel for combustion. This ratio may be different for any number of reasons, but let's just use this.

#1- Aftermarket air intake systems promise more air actually getting to the turbo unit. Does this also mean an increased volume of air going *through* the turbo in the same amount of time, or just a greater volume available at the intake end of the turbo for the turbo to draw upon? (Comparing the sizes of OEM and aftermarket intake piping, there is no doubt that more air volume is provided up to the turbo.)
This is actually really complicated. In the case of our intakes on this car it's two main things. First the air at the turbo's inlet is more dense because of higher pressure and lower temperature. That means that the turbo doesn't have to spin as fast to build up the full amount of boost. The second is that the air going to the intercooler is a little cooler, thus the air after the intercooler is a little cooler. The result is a more dense air charger per pound of boost, so yes, more air, but also more ignition timing since the engine is farther from the knock threshold due to the lower temperature.

#2- If more air per unit of time is actually going through the turbo with the aftermarket air intake systems, would this also mean more fuel needs to be introduced into the air stream as it enters the combustion chamber? (Edit, with claims of better acceleration and increases of power, I'd think more fuel is being delivered to maintain the proper air:fuel ratio.)
Yes, the ECU will automatically add more fuel. Exactly the same way it knows to add more fuel when it's cold outside, or to add less fuel with less boost.

#3- Are current users of aftermarket air intake systems noticing changes in your fuel economy numbers (figured manually, using actual miles driven divided by actual gallons used, not via dashboard mpg meters)? If so, what are before/after upgrade mpg figures?
If you keep your foot out of it you won't have a decrease in fuel economy

#4- Unless I've missed something in message conversations or mfr. product details, when using aftermarket air intake systems, is re-mapping of the engine's computer required, or at least suggested? (Edit, or is the factory mapping able to compensate for the greater air delivered with added fuel to maintain the proper air:fuel ratio?)
Remaping is not required. The ECU is more than capable of noticing this change. To the ECU is essentially looks like slightly superior weather conditions.
 

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Discussion Starter · #7 ·
Thanks for your detailed reply, Greg, just what I was looking for!

Steve.
 
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Greg nailed it, as usual.

Lower intake temperatures are always desirable, especially when they are consequential. Any effort to improve that, especially in warm climates or on warm days, is a worthwhile investment.

Reducing intake temperatures has a secondary effect of allowing the turbo to move more air at a lower pressure. Remember, PSI is just resistance to flow, and any compressor becomes less efficient the more pressure it has to produce to overcome that flow resistance.

The improvement in flow from a different air filter may not be consequential, but every little bit helps. Look at it in terms of how your modifications affect the whole system, not a single metric. All of these performance-improving modifications work together.

You really ought to consider exhaust work. The Abarth picks up 4hp from exhaust alone, and this engine really does produce a rather nice exhaust note.
 
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