Diy Inlet Manifold Pics

[getuted]

I've been busy in the shed last couple of months machining parts for a 6061 billet inlet manifold for an engine I'm building for my BA 2 turbo ute, I still have a lot of machining to go but its getting close to welding the runners to the plenum plate and cylinder head plate then I can start on the plenum. The end result should be something similar to a hypertune manifold except it will be welded together.

[Justa6]

Wow that's smick. Got some skills, well done. keen to see the end result.

[spinr33]

Looks good mate good job

[Mr_4.0]

Have you done computer modelling for this yet?

[getuted]

I spent about 20 hours taking measurements and doing drawings on my PC. I didn't have access to flow modelling software however once the manifold is finished the head and the manifold are off for cylinder head porting. I want to get get the head and the manifold runners flow matched so each cyl is getting equal air distribution. This is the one reason I made the runner wall thickness .170" so they have some wall thickness to play with. I also dropped the port height .060" so more of the valve top faces are exposed by taking more out of the bottom of each cylinder head port.

[Mr_4.0]

The shape and size of the plenum will help determine the air distribution as well. Try get a hold of some modelling software. It's well worth it. A lot of aftermarket plenums on the market that due to their shape, do not distribute air evenly at all.

[BRK]

Looks great. The flow matching will not be easy if you go for a front entry for the throttle body. Saw this sort of work done on on a manifold built for an RB30 that was supercharged and it took the builder a fair while to get this sorted. Without lecturing, their are clearly air currents in intake manifolds caused by each cylinder drawing on each intake cycle and the longer the manifold, with the throtle body at the front, the more severe these get. Replicating this on flow benches is pretty hard. However, if you get the head and intake tubes to be "neutral" - all ports basically even - then you can work in the intake manifold plenum design to try to get this sorted. Software will help with this. When you look at the aftermarket for, say, early Nissan 2.6LGTR's, you can see what they do in terms of design and I guess we cannot argue with their success. The Ford FG "log" seems to work pretty well despite its' basic look and there are some who say that this centre feed design is the best option for forced induction.

BTW - The VL manifold worked out pretty well. It wound up with a teardrop shaped plenum ( larger volume at the rear) along with some metal pieces inside to help direct flow plus short ram tube tops on each of the runners. On the engine dyno, the exhaust port temps were about the same and it ran pretty well in the car. It was ages ago now but it was a lot of work back then and not that scientific, but it worked out. All power to you for doing this - good luck!

Edited 10/06/13 11:25 PM by BRK

[Skids4kids]

The shape and size of the plenum will help determine the air distribution as well. Try get a hold of some modelling software. It's well worth it. A lot of aftermarket plenums on the market that due to their shape, do not distribute air evenly at all.

The bottom half of the BBM manifold is not even in flow just in case you weren't aware:)