Thread: Snorkels

Originally Posted by BadCo.

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I was looking at the Safari Snorkel for the County V8.

Would this be big enough for the 4BD1? I can't get anyone to confirm the diameter of it.

Any other suggestions?

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That's was an interesting enough question to get the brain kicking over, so I fired up Excel.



The way I see it, you're interested in comparing flow rates through the snorkel between the different engines. For a simple (good enough) calc; you need the Max RPM, engine swept capacity and the intake pressure.

Now it's important to note that this ignores the volumetric efficiency of the engine - as well as the fact that fuel enters the cylinders with the air - but as we are ignoring that with all of the engines and as we are only interested in comparing them it is acceptable IMO.

So as you can see, the N/A 4BD1 uses less air than a 300Tdi when going all out. A 4BD1T at 15PSI uses more, but still only as much as a V8 (which uses the same snorkel). Even then I think there's still a fair safety margin built in.

To check my results I went looking for somebody else who had tried to figure out the same thing. Donaldson have this information sheet on the topic and their method gives the same results, but they use magic numbers and imperial units and we can't have that

[ame="http://india.donaldson.com/en/engine/support/datalibrary/065857.pdf"]here[/ame]

For some real world info. The existing 4BD1 intake tract (3") mates up to the Safari snorkel well, but the snorkel is designed to mate to the 300Tdi (2.5" from memory) intake tract as well. The snorkel is tapered where it joins to the tract, so you trim the 2.5" diameter part off up to the 3" diameter part.

Awesome info, thanks for that Dervish. I was hoping the safari 3.5" and tapered down to 3" but by your calculations the three inch should be enough.

I would have thought that the snorkel would need to be larger then the intake diameter to compensate for the added length...

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Originally Posted by BadCo.

Awesome info, thanks for that Dervish. I was hoping the safari 3.5" and tapered down to 3" but by your calculations the three inch should be enough.

I would have thought that the snorkel would need to be larger then the intake diameter to compensate for the added length...

I wasn't referring to the actual snorkel bit - I don't know what diameter it is - I was referring to the bit that sticks out inside the guard. It is 3", then steps to 2.5" so you lop the 2.5" bit off.

Ah I see what you mean now. So the hose that comes with the V8 kit is only going to be 2.5", as it looks like it comes with a reducer.

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Originally Posted by MVFrancis

I won't be home till sunday, but ill take some notes when I get into the shed then.

Ive also got a v8, so out of interest I'll measure that up too.

Cheers

Its suuundayyyyy, have you had a chance to look?

I did indeed.

The one on the county only has defender written on it, not safari like the perentie one does. Couldn't find a part number either unfortunately. But I'm pretty sure it's a safari as otherwise it looks identical. The only exception is that where the tdi one has the step down to 2.5", the one on the county is a 3" with no step down. I thought it was a bit strange and someone may have cut it off, but had a really good look and it appears to have been made like that.

So, with that in mind, if you were going to lop the end off the tdi one anyway, I'd just be buying whichever you can get cheaper.

Cheers

Awesome, thanks for that. I have seen that defender one in person and it looks all good and about the same price.

Did you manage to measure the inlet/ snorkel head?

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Didn't think to do that sorry. Ill do it tomorrow when i fit the pre cleaner though!