Benifits of a Snorkel?

[KiwiBacon]

The mav is dual fuel and I just did a longer trip (than normal) on gas on the highway, had the snorkel head facing backwards (to stop bugs going straight in). It would only get to about 100kmh (with 36's so about 120) but no quicker. I stopped on the way and turned it forwards again. When I did, I could get it to 120 (145ish). Plus the difference in torque at lower speeds with the cooler air is definitely noticeable which is one benefit of a snorkel.

To drive a vehicle at 145km/h requires 76% more power than driving at 120km/h. You can't almost double/half an engines power just by turning the snorkle head around.

[BadMav]

To drive a vehicle at 145km/h requires 76% more power than driving at 120km/h. You can't almost double/half an engines power just by turning the snorkle head around.

I never said that, besides where do you draw those figures from? Mine are fact because the pedal wouldn't go any further. Why is everyone so down on snorkels? "dmck" asked whether snorkels are useful on lpg vehicles or to just look good. My vehicle runs on LPG and in my circumstances it is an improvement.

[KiwiBacon]

I never said that, besides where do you draw those figures from?

Basic laws of physics. Wind resistance is the biggest power draw in a moving vehicle, the force to overcome that wind resistance squares with speed.
Power is force*speed.
Hence power to beat wind resistance cubes with speed.

145km/h is 1.208 times faster than 120km/h, 1.208^3 = 1.76.
Hence 76% more power to do 145km/h than 120km/h.

[DEADZOOK]

owned

[Guy]

I never said that, besides where do you draw those figures from?

Basic laws of physics. Wind resistance is the biggest power draw in a moving vehicle, the force to overcome that wind resistance squares with speed.
Power is force*speed.
Hence power to beat wind resistance cubes with speed.

145km/h is 1.208 times faster than 120km/h, 1.208^3 = 1.76.
Hence 76% more power to do 145km/h than 120km/h.

What would for sake of argument happen to a motors output if airflow was restricted by say 10-15%.
It would be interesting to see the figures\flow patterns of a 4x4 in a wind tunnel with the head forward and head backward ..as it may not be as simple as the placement of the head itself as other interaction of flow with the roofline etc may play a role in airflow or createing a low pressure zone as well.

[KiwiBacon]

What would for sake of argument happen to a motors output if airflow was restricted by say 10-15%.

Power and torque would reduce by roughly that amount.
10-15% is a massive restriction. A snorkle won't do 1% gain at 100km/h, how bad a loss can be depends on how bad the pipework can be.

[Struth]

and if I put a small magnet on the fuel line, install a hyclone on the intake and drop a moth ball in the fuel tank I will reverse gravity and my fuel econamy will be so good it will actually reverse and start making fuel which I can then sell back to the fuel companies

Bugger me I was going to add something similar, but you have it in a nutshell

[Tiny]

and if I put a small magnet on the fuel line, install a hyclone on the intake and drop a moth ball in the fuel tank I will reverse gravity and my fuel econamy will be so good it will actually reverse and start making fuel which I can then sell back to the fuel companies

Bugger me I was going to add something similar, but you have it in a nutshell

well glad to see someone else supports my theory

[BadMav]

Basic laws of physics. Wind resistance is the biggest power draw in a moving vehicle, the force to overcome that wind resistance squares with speed.
Power is force*speed.
Hence power to beat wind resistance cubes with speed.

145km/h is 1.208 times faster than 120km/h, 1.208^3 = 1.76.
Hence 76% more power to do 145km/h than 120km/h.

Sounds pretty convincing KiwiBacon, even with that information I still can't explain how much better mine went with it facing forward. All I can put it down to is that the forward facing snorkel head was enough to get into it's optimal rev range where it could keep accelerating or maybe there's one of those madmax superchargers hiding under there somewhere.

[stripey]

back to topic benefits of a snokel for me are peace of mind that im not going to drown the engine , being in tassie i dont have the issue with dust . also i think the sound of the air being sucked into the snorkel with the muffled sound of the engine while standing next to it is tops.

[Wambat]

and the only reason people face the head backwards on their fourby is to stop mud and stuff getting flung into it buy them or a car in front

Bullshit, I have spoken to people who do it to there comp cars, and certain cars with certain snorkle setups actually improve with reverse facing heads.

well that is to be expected, most comps are not at that high a speed, so they wouldnt notice any difference between the head facing forward or backwards, at low speeds its not hard to get the air in, the only argument here being at speed(100k + ) that if its facing backwards you may get a small vacuum, which is nearly next to nothing and not worth the hassle.


and just for your info, when i eventually fab up a snorkel, it to will be facing backwards, for the reason i first mentioned, to stop shit getting in there when i play in bog holes

[KiwiBacon]

and just for your info, when i eventually fab up a snorkel, it to will be facing backwards, for the reason i first mentioned, to stop shit getting in there when i play in bog holes

It'll catch a whole lot fewer insects and leaves on the road too.

[Struth]

back to topic benefits of a snokel for me are peace of mind that im not going to drown the engine , being in tassie i dont have the issue with dust . also i think the sound of the air being sucked into the snorkel with the muffled sound of the engine while standing next to it is tops.

The main benifit is to stop water and dust getting in.

Dependant on where your cars original air pick up was it may also add a cold induction effect.

My car gained 25 Rwkw when it went from sucking air from under the bonnets to sucking air through the first 3" snorkel.

Converting that to a 4" snorkel added 5 Rwkw and brought peak power down from 4800 rpm to 4200 rpm.

It also increased power by 20% at 2500 rpm.

All of these figures were measured on the same dyno, so to me at least it is proof that snorkels and snorkel design will increase engine power.

As is to be expected whenever a better induction system is added to a vehicle.

Cheers

[KiwiBacon]

My car gained 25 Rwkw when it went from sucking air from under the bonnets to sucking air through the first 3" snorkel.

You're always going to find a far bigger difference on a dyno than on the road. On the road you've got far more air movement and far lower under bonnet temps than on a dyno with just a fan in front.

[Struth]

My car gained 25 Rwkw when it went from sucking air from under the bonnets to sucking air through the first 3" snorkel.

You're always going to find a far bigger difference on a dyno than on the road. On the road you've got far more air movement and far lower under bonnet temps than on a dyno with just a fan in front.

That is correct but 25 rwkw cannot be argued with as a benifit just from introducing cold air, nor can the drop in the rev range by 600 rpm of peak power.

Direction of the snorkel head is a completely different matter.

Cheers

[KiwiBacon]

That is correct but 25 rwkw cannot be argued with as a benifit just from introducing cold air, nor can the drop in the rev range by 600 rpm of peak power.

Direction of the snorkel head is a completely different matter.

Cheers

The only thing I can think of that will drop peak power down the revs is an airflow restriction which drops torque and power at higher rpm.

[Struth]

That is correct but 25 rwkw cannot be argued with as a benifit just from introducing cold air, nor can the drop in the rev range by 600 rpm of peak power.

Direction of the snorkel head is a completely different matter.

Cheers

The only thing I can think of that will drop peak power down the revs is an airflow restriction which drops torque and power at higher rpm.

It demonstrated more power at lower RPM, which to me could be the result of removing an air restriction (the 3" snorkel being replaced by a 4"), it is by ongoing development of my engine conversion that I am discovering these things. It has just had a larger air cannister added with a factory paper element, the results make the engine feel a lot stronger as compared to the old cannister with oiled pod in it, unfortunately I don't have the dollars to throw at another dyno run ATM.

But wouldn't an air restriction reduce power at the same time as moving it down the rev range, not increase power while moving it down the range?


Cheers

[KiwiBacon]

But wouldn't an air restriction reduce power at the same time as moving it down the rev range, not increase power while moving it down the range?


Cheers

Air restrictions are most noticable at high flows. Pressure losses build with velocity squared.
So at 4000rpm you'd have 4 times the pressure drop as at 2000rpm.

I'm thinking colder air gave you the lower end boost (exaggerated on the dyno, but still there on the road) but you picked up an extra air restriction due to the extra length of piping and extra corners.

[Struth]

But wouldn't an air restriction reduce power at the same time as moving it down the rev range, not increase power while moving it down the range?


Cheers

Air restrictions are most noticable at high flows. Pressure losses build with velocity squared.
So at 4000rpm you'd have 4 times the pressure drop as at 2000rpm.

I'm thinking colder air gave you the lower end boost (exaggerated on the dyno, but still there on the road) but you picked up an extra air restriction due to the extra length of piping and extra corners.

I see what you mean but the 4" snorkel is the same length with one less 90* bend before reaching the cannister. Probably the cannister was the major restriction I introduced as I changed this at the same time I upgraded the snorkel and it did not allow a lot of space around the pod filter.

Probably better/more flow gave me the boost as the extra kw at lower revs was between snorkel sizes

Cheers

[NQCalais]

Most new petrol 4wds will run under water as much as a diesel as long as you do not drown it. Snorkels are great but do not assume that if fitted by a professional fitter that they are fully sealed. Check them.
Cris

Easiest way to check I've seen so far (on a diesel) is grab a can of Contact Cleaner and spray it on all your joints. If there is a leak the revs will climb a little bit as the ether combusts.

Not sure if this works on a petrol, but prob should?