c/x16xe exhaust ports & intake plenum designs

[Sirnixalot]

I'm doing some preliminary design work on some bits i want to fab up for my c/x16xe conversion later on in the year.

Looking at the exhaust manifold gasket the ports are kinda shaped like a pair of tits.



Is it possible to remove this rise in the middle and make the ports oval?

I'm trying to design a log manifold for a turbo....just bored and practising CAD really. This is what i have so far


I'm also designing an intake manifold (on that note does anyone know how long the runners are on the lower part of the c/x16xe intake manifold?)

I need to adjust the dimensions on the upper half of the plenum but you get the idea




Hazarding a guess at a 12" runner length and an equivalent 1.8" runner diameter a 1920cc plenum volume with a TB with a 60mm plate it would be ideal for peak torque around 5000rpm, ive tried to design it as a hemholtz chamber as well but im only guesstimating at the standard camshaft duration (if anyone knows it would be a great help as well).

[maccas]

the lump in the bottom of the exhaust ports is to do with the egr system, it can be removed as far as i'm aware as the lump only rises up about half an inch back into the head if you get me? before the lump in the head the port is an ordinary oval shaped port if that makes sense? if i was at home i would measure the lengths of the runners for you but i'm at uni so i can't help with that sorry, hope that helps

maccas

[Adam]

The ports in the exhaust manifold are nothing do with the egr system. EGR is all on the inlet side of the head.
They are for the secondary air injection system.

Not sure if you could make the exhaust ports an oval, i dont really see much point in that tbh.
Just get an exhaust manifold that blocks the SAI ports....

I could measure you the runner length of my x16 lower inlet(the c16 lower inlet is different, the top isn't flat)

Std cam duration is 241deg, 8.45mm lift iirc.

If you need any pics of anything let me know, as my x16's in bits atm,Lol.

[maccas]

apologies

[Adam]

Lol

[maccas]

sorry to hijack the thread slightly but it is along the same lines, am i right in thinking that the c16xe doesn't have the secondary air injection system? and if it doesn't does that mean that it doesn't have the same shape exhaust ports as the x16xe? would the c16xe exhaust manifold enable me to block up the SIA holes? many thanks

maccas

[Adam]

I think a c16xe exhaust manifold would block them yeah.

Its easy block on a x16 tho, just remove the valve from the top of the manifold, and make a alloy plate(ive used 5mm plate), and bolt that over the hole with the gasket.

Ive done the same for the egr too.

[Sirnixalot]

LLTN, can you take a pic of the standard exhaust manifold flange looking into the runners?

also the same with the head ports if its not too much trouble.

the reason i would like to grind those bits down is it will take alot more work to make that shape. sch40 carbon steel elbows arent the easiest things to shape .

[Adam]

A pic borrowed from ebay,Lol.

The std manifold is identical ports, bar having a small oval hole under each port(for the sai)

Can do pics of mine later/tomorrow if you need them.

[Adam]

X16xe exhaust ports:
There should be a small oval hole under each port, but mine have got slightly blocked with carbon deposits,Lol.