Porting templet and matching issues 325i head

[Chuckcruzin1986]

Hello,

I made some templets, one to fit the head and a unit with larger holes so I could index accuratly on the intake manifold (325i head 885) using gage pins.

I was amazed how perfectly each port matched the next one on the head. When I put the other templet on the intake manifold I was shocked to see how much smaller it was. I am guessing that it was designed into the engine with the idea that it would be better to run into a larger hole for the air to hit and cause turbulance.

So, now what to do. I am thinking of grinding the intake ports larger but still about .5mm smaller then the head. Ideas out there?

I am looking for a swift running engine but as an example I am using the original cam (trying to keep my costs down).

Thanks, Chuck

[nando]

your idea is fine. you could make them match perfectly and that would be fine, but you definitely don't want a step up going into the head. that's probably why it was made smaller.

nice templates btw! how much did that cost to make? I have a spare intake I want to port, those would be great

[vr2jetta]

Yea, I gasket matched the ports on mine and it runs great. Stock cam as well.

[Chuckcruzin1986]

Cost of templets?

I machined them on my cnc machining center.

I am in detroit and work for free due to the depression so they were FREE :p

Chuck

PS 3 hours of work

[Aptyp]

can you makes some more of those? I'd like to have a template for my build.

[AndrewBird]

Why not just use a gasket? Then port match both the head and the manifold to the gasket.

[nando]

Why not just use a gasket? Then port match both the head and the manifold to the gasket.

gaskets are pretty flexible

[416stroker]

Why not just use a gasket? Then port match both the head and the manifold to the gasket.

Because people like to over due things.