Heads.

[Rosssub]

 Koom said:

It\'s the inlet ports that shouldn\'t be ultra smooth as it actually decreases the flowrate. It\'s all to do with the boundary layers created as the air flows through.

But smooth surfaces on the hot side is to prevent carbon buildup which is worse for flow etc

The boundary layer of air, created by slight texture to the intake ports. Also helps stop fuel particles sticking to the port walls.

[Rosssub]

Version 7 WRX/GDA, EJ205. Heads stamped RH S20 and LH S20:

A single stripe on the camshafts and solid bucket valve lifters:

[Zach]

Cool read and thanks for the pictures

[Guest]

I've gone tt heads on my rebuild, just ported the inlet and port and polished the exhaust plus went shim less on a version 8 sti block. Good to get confirmation that the heads are indeed bigger than the v6 sti ones from factory, I was told this by my builder which is why I went that route.

[ADIKT]

 ballsrburning said:

I've gone tt heads on my rebuild, just ported the inlet and port and polished the exhaust plus went shim less on a version 8 sti block. Good to get confirmation that the heads are indeed bigger than the v6 sti ones from factory, I was told this by my builder which is why I went that route.

You must be pretty bloody close to driving yours!

[Guest]

 ADIKT said:

You must be pretty bloody close to driving yours!

yes and no, only need to wire up oil pressure and temp sensors to the digital dash and sort out vacuum lines and I can start it.

However, landlord as offered us our house to buy, misses likes the house so car waits until I get money for deposit, only two months though hopefully as got some savings for it already. But its a bloody nightmare so close to finishing it and have to wait.

[ADIKT]

 ballsrburning said:

yes and no, only need to wire up oil pressure and temp sensors to the digital dash and sort out vacuum lines and I can start it.

However, landlord as offered us our house to buy, misses likes the house so car waits until I get money for deposit, only two months though hopefully as got some savings for it already. But its a bloody nightmare so close to finishing it and have to wait.

House>Car

Epicly close though!

[slystiguy]

Thought it might help some peeps if I add some details for ej20r heads

[Rosssub]

Nice work. Here's EJ20K V3/4 STI cams/shim under buckets, courtesy of Tydon:

 tydon said:

[slystiguy]

Cheers dude! I'll upload some better pics when I have had them dipped and cleaned ect. Note the cross hatching pattern on the inside of the head. This could be present on all of the phase 1.5 heads though as I have read they all use the same casting but the valve assembly is different.

Hey Rosssub do you happen to have any more information on cam identification? Or would you be able to point me in the right direction?

It would be very interesting to document all the different types of cams so we can accurately identify heads by the markings on the cams

Added a couple from my google findings

http://bbs.22b.com/forums/showthread.php?10688-V3-sti-heads-identification

http://www.scoobynet.com/scoobynet-general-1/825436-how-to-tell-v4-sti-heads.html

[DacerX]

Ill be posting up some pics of my V2 sti ra heads tomorrow when i get ahold of them

[Rosssub]

 slystiguy said:

Hey Rosssub do you happen to have any more information on cam identification? Or would you be able to point me in the right direction?

It would be very interesting to document all the different types of cams so we can accurately identify heads by the markings on the cams

Nah sorry, hopefully we'll have most covered by the end of this thread. Kamineko mentioned on page 2 he was working on a list of cam markings.

[Rosssub]

BE5D/BH5D (Rev D) heads stamped RH H20B and LH H20B. Still using over bucket shims, with a single stripe on the camshafts. Pics courtesy of A_J_T:

[kamineko]

Ive been compiling cam ident info for years. Will be posting it up in the holidays next week

[SWAGGN]

I've got some b4 heads (shim over bucket) that I'm using for a forged build, how hard is it to convert them to shim under bucket?

[Rosssub]

You'd have to change the valve retainers over to suit the under bucket shims. Not too bad if you have the right tools. Then you'll probably want to change to the stiffer STI valve springs as well anyway. Resetting the valve clearances takes the most time and effort.

Solid buckets will go in without changing the valve retainers, so be a better way to go. Just the solid buckets are a lot dearer if you need to change a few to get your clearances right.

Here's the BE/BH shim over bucket valve spring retainer:

Here's the V6 STI shim under bucket valve spring retainer:

V7 solid bucket valve spring retainer: