Efficiency Spreadsheet

I made this spreadsheet a while ago, trying to illustrate why cold air intakes are pointless and it got burried on my laptop somewhere. Anyways, I dug it out for MINI2 thread and figured I'd share it with you guys too (aint I swell?). let me know if you have any questions. Tweak it as you see fit, all the cells should be unlocked.

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Cheese

 

That's very Krafty, MacnCheese.

I posted awhile back questioning why almost none of the European tuners, including JCW, were using an intake given that it is such an easy modification. Is this my answer?

If this is true, why do dynos show gains with intakes?

See ya,
JS

 

dynos show gains on intakes due to increases in flow/decreases in restriction (negative boost), this is an adiabatic (temperature) thang.


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Cheese

 

This is for a boosted/blown/turbocharged vehicle just to make that clear.

The 'adiabatic' effects on an N/A engine will be very helpful, while the air going through a supercharger will get heated up regardless, and then cooled at the intercooler, so a 'cold air intake' will do almost nothing, save for the potential for higher flow filters.

 

I think I kinda sorta understand...maybe. :smile:

See ya,
JS

 

What type of charge cooler (intercooler) is being used for these numbers? Air-to-Air? Water-to-Air? No intercooler? I'm not much of an air scientist, does the spreadsheet already have an area for temp drops due to good intercooler workings?

 

are you saying air intakes dont add hp period? if so why would racing teams use them? i dont quite follow what you are saying.

jstines this could be your answer. it came from a previous post.

hope this is helpful

 

>>What type of charge cooler (intercooler) is being used for these numbers? Air-to-Air? Water-to-Air? No intercooler? I'm not much of an air scientist, does the spreadsheet already have an area for temp drops due to good intercooler workings?

The spreadsheet accounts for an intercooler with an efficiency of 72% being cooled by an ambient air temp of 65F. You can download the sheet and tweak this numbers as you see fit. I think low 70s is an average efficiency for an intercooler.


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Cheese

 

>>are you saying air intakes dont add hp period? if so why would racing teams use them? i dont quite follow what you are saying.
>>

Im not saying that intakes dont add power. I'm saying that there is little to no benefit from a "cold air intake" compared to a short ram style intake. The heat shield is doing little but emptying your wallet (And holding up the battery cable :smile. Hope that clears it up.

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Cheese

 

Most race teams don't use an open element style of intake. Look at a formula 1 caror a CART or IRL car and they all have carbon fibre air box's. With a big ole scoop pulling in fresh air.

Cheese hit the nail on the head, the other day at the track I felt the inside of Andy's heatshield and it was hot. I'd venture to say the temps right aorund the filter were the same as in the rest of the engine bay. The metal in the heatshield acts as a heat sink just taking in the heat. I'm going to try just sticking a big K&N cone in the bottom of the air box and running a fresh air feed from the vent near the window.
Mike

 

hey macncheese, can you repost the spreadsheet?

 

http://www.ross-tech.net/andy/mini/C...Efficiency.xls

 

. I'm going to try just sticking a big K&N cone in the bottom of the air box and running a fresh air feed from the vent near the window.
>>Mike

I have actually been considering doing just that but havent had time to take the air box apart. Is there anything the connect the cone to? I figured a small pipe connected to the tubing from the intake through the air box and on the cone filter. A little metal to plastic glue and bang, $50 K&N kit.

BC

 

Ie tried the BMP,K&N Typhoon and rogue and now the Pipercross Viper By using the indoor /outdoor thermometer as per the original post in this thread I have ambient temp hitting the face of the filter element. If you can see it the entry for the filter is actually thru the rear bulkhead and drawing air from the vent at the base of the windsheild.I have also inuslated the inside of the aluminum box on the inside with styrofoam to prevent the transistion of heat further. The first pic shows the box with the styrofoam liner and the second older shot shows how the intake goes thru the bulkhead..
Page Title maxmini home site

 

So does it make any performance difference?

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Cheese

 

One suggestion. Do not use styrofoam, use only foil backed fiberglass. Stryofoam has a very low ingition point. I work work for a tier one automotive supplier and you must be very careful when insulating in the engine compartment of todays automobiles.
Neal