Outer Limits 4x4 Board

Does any know where I can get hold of Flexible Air Hose Diameter 3 1/2 inch (90mm). I need to redirect my Air Cleaner to a new Snorkel?
Would prefer Vic supplier

there's probably cheaper places but "purple pig" would most likely have it.

Matt

Pirtek or similar.

evil_hitman wrote:there's probably cheaper places but "purple pig" would most likely have it.

Matt

x2

Purple Pig in Stawell will have it or get it.
Make sure its hi temp suction hose too.

Go to clark rubber, its called seeder hose.

Purple Pig. The ideal product used to be known as RFH ducting. It was dear as poison but lasts for years.

I saw something similar at Clark Rubber but didn't investigate.

Steve.

I bought some plastic ducting at Nightingale's in the city. I wasn't looking for it at the time but it was under $10 a metre so I just bought three metres.

It's not super flexy, but it works in my GQ engine bay and it hasn't melted or anything yet either.

I am certain it's not the absolute best stuff around but it is so cheap it's worth a go.

Remembering corrugated hose is about the worst possible thing you can do for an intake restriction.

Flow tests on corrugated hose shows massive drops.

45% of intake flow restriction on WRX was the section of corrugated hose before the intercooler. Paper Air filter accounted for 3%.
Other cars tested similar with manometer.

Paul

me3@neuralfibre.com wrote:Remembering corrugated hose is about the worst possible thing you can do for an intake restriction.

Flow tests on corrugated hose shows massive drops.

45% of intake flow restriction on WRX was the section of corrugated hose before the intercooler. Paper Air filter accounted for 3%.
Other cars tested similar with manometer.

I find this easy to believe, but my question is - what difference do you think it would make to real world performance in a fourby?

I can't help thinking that these threads about ram "charging" the air with the snorkel, having bends in the snorkel plumbing etc are a bit over the top for the typical 4WD engine. I drove around for a while with no hose between my snorkel and my air cleaner box, then hooked it up and there was certainly no seat-of-the-pants difference, dunno if there would have been a difference on a dyno of course.

But I could be wrong... how much do you think it matters?

2 thoughts

1. When you got bugger all to push too much, anything helps

2. Check the autospeed tests, but it made significant differences. With a turbo, anything can be overcome. With n/a vehicle, intake restrictions make a huge difference. People spend (waste) hundreds on filters, and ignore the rest. The falcon has a dual length intake runner with butterflys, that way they get "boost" equivalent to 2-4PSI at cruise. Resonant frequency gives 100% intake fill compared to the 80% of 4 valve engines, and the 60% of 2 valve. Intake flows matter enough to spend heaps of time porting and polishing.

Of course this all depends on Engine type, RPM, head design, fuel metering method etc etc.

It was suprising just how bad corrugated pipe flowed. Far more effect than a dirty filter. I know in boats (yes I know - different fluid) a bilge pump will lose approx 50% of low if you use corrugated hose.

Paul

Thanks ppl

me3@neuralfibre.com wrote:Remembering corrugated hose is about the worst possible thing you can do for an intake restriction.

Flow tests on corrugated hose shows massive drops.

45% of intake flow restriction on WRX was the section of corrugated hose before the intercooler. Paper Air filter accounted for 3%.
Other cars tested similar with manometer.

Paul

Have you got an absolute number to put that 45% into perspective?

KiwiBacon wrote:

me3@neuralfibre.com wrote:Remembering corrugated hose is about the worst possible thing you can do for an intake restriction.

Flow tests on corrugated hose shows massive drops.

45% of intake flow restriction on WRX was the section of corrugated hose before the intercooler. Paper Air filter accounted for 3%.
Other cars tested similar with manometer.

Paul

Have you got an absolute number to put that 45% into perspective?

Dig through the old Autospeed articles on flow testing. It was 5+ years ago I was watching that stuff. Doubt the physics has changed though. Search for Manometer

Paul

me3@neuralfibre.com wrote:
Dig through the old Autospeed articles on flow testing. It was 5+ years ago I was watching that stuff. Doubt the physics has changed though. Search for Manometer

Paul

This one?
http://autospeed.drive.com.au/cms/article.html?&A=0646

They've done total pressure drop and drop across the filter. But nothing about corrugated hoses (yet).

This might be the one.
http://autospeed.drive.com.au/cms/article.html?&A=0652

He had 37% of a 16" of water pressure difference across the rubber hose. That's 6 inches of water or 1.5kPa (approx 1.5% of an atmosphere)

But the hose had two bends in it and tapered in size. Replacing it with a smooth hose would be a lot of work for possibly no gain.

So it's bugger all really.

me3@neuralfibre.com wrote:Remembering corrugated hose is about the worst possible thing you can do for an intake restriction.

Flow tests on corrugated hose shows massive drops.

45% of intake flow restriction on WRX was the section of corrugated hose before the intercooler. Paper Air filter accounted for 3%.
Other cars tested similar with manometer.

Paul

I'm lazy find the article for me

45% is a big number, there is also alot of debate about turbulent air vs "smooth" air entering a motor and that the more turbulent air actually creating better fuel atomisation and more power. again this would depend greatly on the head design?

I've also been lead to beleive on a 90 degree bend corrugated is actually better, the outer air in the tubing "catches" on the corrugations causing a tunnel for the air to travel through. This was also from a corrugated ducting supplier so who knows, I'm not a physicist

Back on topic there is a place in laverton that has the high temp corugated flex at around $26 per metre when I brought it... if it's close I'll dig around and get the name for you.
Simon

You can get that canvasy looking stuff with the wire reinfocement (?) from Industrial Mining Supplies in Greens Rd, Dandenong.

KiwiBacon wrote:This might be the one.
http://autospeed.drive.com.au/cms/article.html?&A=0652

He had 37% of a 16" of water pressure difference across the rubber hose. That's 6 inches of water or 1.5kPa (approx 1.5% of an atmosphere)

But the hose had two bends in it and tapered in size. Replacing it with a smooth hose would be a lot of work for possibly no gain.

So it's bugger all really.

Similar
If my memory serves they did same with WRX. The y pipe before the intercooler was corrugated.

45% is not 45% airflow reduction, but 45% of total inlet restriction. If you want to shrug it off , but after pletny here looking for 0.0003% from a snorkel and 0.000025% from foam air filters.....

The main point I remember was the dirty airfilter accounted for some 3% of total intake restriction, versus 30 or so% from the air flow meter and another 40% from corugated pipe. I stopped worrying about paper filters after that.

Paul

shakes wrote: 45% is a big number, there is also alot of debate about turbulent air vs "smooth" air entering a motor and that the more turbulent air actually creating better fuel atomisation and more power. again this would depend greatly on the head design?

By the time the air gets into the cylinder, there's plenty of turbulence.