Quote:
Originally Posted by SenorFunkyPants
Hmm I've seen other comprehensive dyno tests of these scoops that showed absolutely no gain whatsoever.
But as snake oil goes it not too expensive.
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Quote:
Originally Posted by acuteperformance
Do you happen to know where? I'd love to take a look. 
Michael
Acute Performance |
Excuse the delay in replying:
"Experiment :
To see if Rpi Scoops;
- Help lower intake temperatures
- Help engine consume more air
- Help with airflow
- Help with power
Test 1:
Using fan with approx wind speed of 90-100mph directed straight at front kidney grills with and without scoops.
To test if any change in air mass sensor readings in kg/h over a period of 2 mins under static full load @ 3100rpm.
Result:
Average consumption of air increased by 0.5 kg/h with scoops. This basically means the scoops don't create an effect where any additional air, or anything that can be called even close to minute, is forced into the engine. The air mass meter readings clearly tell us this.
Test 2 (done in conjuction with Test 1)
To see if Rpi scoops lower air intake temperatures AND if they allow temperatures to fall faster from 41 over a 2 min time span under full load @ 3100 rpm
Result:
No reduction in air intake temperature over a 2 min period. Air intake temperatures not falling any faster.
Test 3 - Full Power Dyno run
Result - zero difference accross the entire rpm range. With and without scoops overlay each other perfectly. Even the fuelling is exactly the same.
Conclusion:
The scoops do absoltely nothing whatso ever. Air mass meter readings don't change, air intake temperatures don't change, fuelling is exactly the same.
The engine is consuming the exact same amount of air as per the air flow sensor.
I have one further test to do and I'll do it on the way home - data log the average intake temperature with and without scoops (25 miles each). All A road and motorway driving.
If anyone wants the dyno charts or excel sheet with the logs on there please do not hesitate to contact me.
Finally, we already knew these things don't work because of how effective the factory airbox is and how well it flows.
Just have a think about this and I'll put it in very basic terms.
This engine has the capacity to 'suck' as much as 1000 kg (without even thinking about it) of air per hour. Do you really think your going to force feed it anymore with a bit of air pressure?
The standard factory airbox already has external air feeds and it's a well pressurised system. How much more pressure would you require to actually increase to a level where it's forced in?"
"Back to the scoops. Just delivered the car back to the customer with all of the datalogs represented in excel.
He is not happy and wanted to see the data for himself so I've just come back from 1.5 hours with of road driving with him recording differences in temperatures and air mass readings with and without the scoops. Not surprisingly, the road data matches up to the dyno data quite well but the on road testing clearly shows coolant temperatures to be affected more.
Some information that shocked me though - the difference between ambient and intake temperatures are larger on the road than on the dyno.
On road the difference is always 7+ degrees even at xxx+ speeds.
On the dyno the intake temps are only 3-4 degrees higher than the ambient."