Need Advise about evo3 engine mod...

[midzuan]

Valve seal original 1 pcs = Rm13 x 16=RM208. Valve cover gasket around RM 55.

Labour charge depend on your foreman coz some foreman just open up the valve cover and some of them need to take out the hold head (expensive a bit).If u thinking to do top overhaul, it's a good time to change.

 

[oly]

orait bro...tq....

 

[jinkl]

contact centuryautoparts from zth
he can get u "viton" valve seals, better then stock mmc
if got more cash then u can opt for Supertech hehehehhehehe

labour around rm100 like dat la

 

[evo5755]

thts for your current evo's, for the older generations , whts left for us even by HKS is the cast iron , whts used by our custom welders & china made manifolds for the CD9A are not same as the CN series and above which is produced by Tomei & etc , and there are diffrences between wht we use and wht they use in GT300/500 , Nickel content & carbon content are not the same, welding material n concept isnt the same :) , checkup on stainless steel grades... 301 , 302 , 303 , 304 , etc

even if we use stainless steel , we use it for months to years , track cars :) , i wont be suprised they change it at every race event , of cos stainless steel has its advantage which is equal length runners & easier fabrication , easier to design and extract more power but durability isnt on par with the casts

some hardcore users use SS 321 material, just compare the material price with SS 301 and 304 which is commonly used :D

Very interesting topics...

i was in the metal manufacturing before, and SS304 is a very strong material and of course very expensive material. What makes SS so special is their resistance to corrosion is high. some others SS grade have very high anti corrosion until they can be used in parts that are dipped in the chemical.

Well going back to "banana", the metal is being exposed to high heat of exhaust, lets say around 600-700 degress celcius constantly. But need to check back what is the melting point for SS, as i think it can take on high heat before they have any alteration or changes in their materials property.

From my opinion, there are only 2 reasons why banana is way much weaker, and the material differences between SS304 or SS321 for banana manufacturing doesnt make much difference.

Firstly banana uses thinner walls compared to die cast iron that have so much more thicker materials, and hence more reinforced strength. The mass for cast iron is so much higher.

Secondly, cast iron do not have joints but banana will have welding joints. Some have a lot of joints to make the banana, some have less, but it is still made up ofjoints and makes it weak point. Turbo is a heavy unit, fully clamping on to the banana, creating stress to the weak point. Added with the engine movement and exhaust movements added with the gravity we have more stress. That is why in track use, the banana wont last as you are revving the engine up and down as the engine have alot of movement. so in the end you will find "crack"

I think the most important part of weakness is the welding technology and true good welding technlogy that you see in highly priced exhaust like HKS,Trust they have nicely welded exhasut seam. These are technology, not some kedai ABC welding. Many tests were done for the welding strength and welding was done by robotic arm for constant welding.

Just my 2 cents.