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SVXMAN2001
12-28-2008, 07:54 AM
I am having the cylinder head of my eg33 cleaned up with a mild port and polish and was considering having the guy install a set of higher performance intake/exhaust valves and springs. I've searched through the site and could find only the set offered by mike (longassname), along with the camshafts, which are no longer separately available.

What performance intake/exhaust valves and springs are compatible with our stock hydraulic set up? Are there any compatible wrx parts?

I could be asking this competely wrong, meaning, I cannot consider what size intake/exhaust valves to get without knowing what sort of cam gears I'll be running, but I thought it i'd ask anyway as I am still a newbie when it comes to this...thanks. chris

YourConfused
12-28-2008, 08:08 AM
I think you could get allot of info by reading Rallybob's posts on here and nasioc.
From what I have gathered the cams offered by Ecutune are just a general higher performance cam that will improve performance of a na, turbo and supercharged motor. It can't be all 3 at the same time, but since you can't bbuy it separately anymore you should look into Delta cams for cams and head work.

This just what I have gathered from the info posted up here.
Good luck.

TomsSVX
12-28-2008, 08:45 AM
The valves are not like anything else. The WRX parts that people talk about are retro fitted. Longer valves, which mean the hydro lash adjusters go out the window and bucket and shim lash adjuster is used. This will help make up for the difference in valve height. Not to mention they use a totally different spring, which there are MANY aftermarket options available. You can also achieve more lift out of the custom cams by using the WRX components because the springs don't reach coil bind quite so soon. So ideally, if you were to keep the stock valves, you are restricting yourself greatly.

Tom

SVXMAN2001
12-28-2008, 09:50 AM
ok, so where do I start? Decide on the camshafts that I want (most likely delta) and then go looking for different valve's with the appropriate springs? Does the type of camshaft dictate the type of intake/exhaust valves? What are our options? chris

RallyBob
12-28-2008, 09:53 AM
I am having the cylinder head of my eg33 cleaned up with a mild port and polish and was considering having the guy install a set of higher performance intake/exhaust valves and springs.

If you are going for a mild build, then the stock valve diameters are fine. The bone-stock head castings and valves flow enough air for 420+ hp. The restrictions are elsewhere in this engine.

I could be asking this competely wrong, meaning, I cannot consider what size intake/exhaust valves to get without knowing what sort of cam gears I'll be running, but I thought it i'd ask anyway as I am still a newbie when it comes to this...thanks. chris

As far as I know, there are no aftermarket options for cam gears out there. Only stock.

As far as cams, Delta and Web Cams both have lots of Subaru experience. Shoot for maximum valve lift (as much as the stock springs will allow), and target more exhaust duration than intake duration. This wakes up the lazy exhaust ports a bit.

TomsSVX
12-28-2008, 09:55 AM
With using the wrx valves, your options are almost limitless. You can get stock sized or oversized valves, soft or super hard springs... I would get the valves, springs, retainers, etc first... Do the porting/polishing you want to do. Valve job... then load the valves into the heads. base your cam specifications off of the measurements you have made. you can decrease the base circle to get exactly what you need... There is no real step-by-step procedure for this, you just need to know what you need/want.

Tom

oab_au
12-28-2008, 04:06 PM
I am having the cylinder head of my eg33 cleaned up with a mild port and polish and was considering having the guy install a set of higher performance intake/exhaust valves and springs. I've searched through the site and could find only the set offered by mike (longassname), along with the camshafts, which are no longer separately available.

What performance intake/exhaust valves and springs are compatible with our stock hydraulic set up? Are there any compatible wrx parts?

I could be asking this competely wrong, meaning, I cannot consider what size intake/exhaust valves to get without knowing what sort of cam gears I'll be running, but I thought it i'd ask anyway as I am still a newbie when it comes to this...thanks. chris

Hi Chris, there is nothing really other that a set of new springs, that is compatible with hydraulic lifters, and hydraulic lifters are not compatible with high rpms.
So if you are not going to run the engine up around the 7500 rpm, then stick with hydraulics and lower rpms.

If you are going to run in the higher rpms then you will need solid lifters, longer duration cams, a exhaust header with longer branches, and a shorter inlet tract. Not to mention needing better rods, and all the other things that it will need to operate reliably, at the higher rpm range.

Of course if you are going to add forced induction, the WRX conversion will allow the use of Sodium cooled exhaust valves.:)

Harvey.