Log manifold - tube sizing
 

I'm in the beginning stages of putting together a log manifold for a single T4 turbo 5.3 build. I work for a tube fabrication company so I have just about every tube/pipe size option at my disposal. My intention is to design a simple passenger side log that fits the fox chassis with an AJE k-member, because it's what I have to work with now.

So the questions I have now are what ID tube or pipe is preferred? Has there been any testing done that supports a certain size?

3" OD is the largest I'd consider since I'm running a T4. I'm thinking something between 2.5" ID and 2.875" ID but honestly, I'm just guessing at it. Fortunately I have several options in this range.

Anyone have any knowledge of log manifold design they'd like to share? Any input is appreciated.

Holley has a new cast log coming out that will fit the Fox body chassis...just saying...

Andrew

Yeah, I'm aware of it but I'd rather have something cool to look at, like a fabricated stainless piece.

personally i'd go with the .125 wall since that'll fit up to a t4 flange pretty nice.
post pics as you make it plz

factory truck manifolds have been 200mph in the 1/4 on a 3500lb drag LSx turbo Fbody..... If you can get past their looks.... they work!

Here's a thread on it.
https://ls1tech.com/forums/forced-in...manifolds.html

Pass thru log on one bank or two individuals that mere at the turbo.

Drivers side crosses over under engine (stock type arrangement) and feeds into a log on the passenger side.