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[Jeepthang]

Just want to get some thoughts on this.

I've got a Safari snorkel that uses a factory adapter to connect to the airbox. The internal diameter of this adapter is 2.5". I want to reroute the piping from the snorkel into the airbox (to remove some of the bends) and go into the airbox from the side. To do this I'm having to make up a new adapter from plumbing parts. The issue is that the new adapter will have an internal diameter of 1.75". I can't find a part that gives me an internal diameter of 2.5"

My question is will this have an impact on the performance output of the engine as effectively I'm reducing the size of the air intake pipe into the airbox by 3/4"

Just to clarify:- The hose through the snorkel to the airbox will be 2.5" (internal diameter) and the hose out of the airbox to the manifold will be the standard XJ hose which I beleive is also 2.5". It's just where the snorkel to airbox hose actually enters the airbox, the fitting that I plan to use only has a 1.75" internal diameter.

I'm wondering whether this will cause any venturi/pressure problems and therefore affect the performance of the engine.

Ta

[Dave69]

the snorkel is just a tube feeding a still airbox with air. the engine will only take what it needs and it is not a ram air setup. so dropping the intake bore 3/4" should not have any adverse effect.

[tim_aka_tim]

At 2.5 inches, the cross sectional area is 4.9 cu in.
At 1.75 inches, the cross sectional area is 2.4 inches.

Thats less than half, so you'd be choking your engine. It would tick over fine, but when you need some air, there's no
room to get enough down the pipe, which is less than half the cross sectional area it should be.

[Jeepthang]

At 2.5 inches, the cross sectional area is 4.9 cu in.
At 1.75 inches, the cross sectional area is 2.4 inches.

Thats less than half, so you'd be choking your engine. It would tick over fine, but when you need some air, there's no
room to get enough down the pipe, which is less than half the cross sectional area it should be.

Oooooooooo! That's very tech but I understand what you are saying! So I'd better continue my search for a 2.5" pipe!

[Bubba]

i agree with tim

[BK]

My mate put a smaller snorkel pipe on his shogun by mistake and now it wont rev over 4,000 rpm!!!

[Jeepthang]

I've sorted the problem now. I managed to fabricate something to give me an internal diameter of 2.5". Once I've installed the airbox into the XJ this week, I'll do a write up on here in case anybody else has a Safari Snorkel and wants to re-route the XJ air pipe differently into the airbox and the benefits of doing so.