2G Looking for advice on head rebuild

[Sjd6795]

So I think to get the experience I am just going to go ahead and rebuild my head myself. I'm not looking to do anything fancy, my car is around 320WHP and I only need to replace my exhaust valves but I figure while it's all out what are other things that should be done.

Also if you could provide brands or links to the parts you'd buy.

Picture attached as to why I am having to replace some the valves

 

[AWD-Tony]

Replace the valve seals, lap valves at minimum. You can clean the casting in both intake and exhaust ports. Jafro has a detailed video on this.

Open up the tear drop on the bottom of the head especially if you’re having it machined.

I’d also clean the casting inside the vent tower.

https://www.dsmtuners.com/threads/a-look-at-the-4g63-pcv-system-engine-internal-view.472405/

 

[Sjd6795]

Replace the valve seals, lap valves at minimum. You can clean the casting in both intake and exhaust ports. Jafro has a detailed video on this.

Open up the tear drop on the bottom of the head especially if you’re having it machined.

I’d also clean the casting inside the vent tower.

https://www.dsmtuners.com/threads/a-look-at-the-4g63-pcv-system-engine-internal-view.472405/

Won't be having it machined.. I've already put about $500 into maintenance as I keep breaking it down further it keeps adding more money. I'll give that thread a good look over, why do you think my valve chipped away in the first place? Did it get to hot because it has to much build up and it couldn't transfer enough heat into the head? Also what website do you recommend using for buying new parts. I found some OEM valves but they was $37 each so not looking to spend that much on a valve job.

 

[AWD-Tony]

From what I’ve read that it’s possibly from leaking exhaust gases. These were mine at about 130k. Got a set of used evo 8 exhaust valves for $15. Maybe try evo forums.

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[AWD-Tony]

I also had 3 intake valves out of round so take a look at those too.

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[1990TSIAWDTALON]

Clean up the used valves and lap them in with compound to see if the seal is good and in the middle of the valve when you get to that point. We do ours. Supertech blue viton valve stem seals BTW.

 

[Sjd6795]

Clean up the used valves and lap them in with compound to see if the seal is good and in the middle of the valve when you get to that point. We do ours. Supertech blue viton valve stem seals BTW.

Good to know thanks, at least the seals are cheap . I can't say the same thing about valves though. I feel like I am going to drop $300 just into replacing valves and I might as well get some cams to toss in there as well.

 

[Sniffbooger]

Well as long as you're gonna throw some money into it, get some roller rocker arms, new 3g lifters and heavy duty springs as well!

 

[Dericsh]

Won't be having it machined.. I've already put about $500 into maintenance as I keep breaking it down further it keeps adding more money. I'll give that thread a good look over, why do you think my valve chipped away in the first place? Did it get to hot because it has to much build up and it couldn't transfer enough heat into the head? Also what website do you recommend using for buying new parts. I found some OEM valves but they was $37 each so not looking to spend that much on a valve job.

my experience with valves that burn like that is with Honda S2000 and not DSM, but I would be looking for a bad injector especially if it’s only one cylinder doing it.

 

[Sjd6795]

my experience with valves that burn like that is with Honda S2000 and not DSM, but I would be looking for a bad injector especially if it’s only one cylinder doing it.

That could be the case.. I swapped to some Delphi 680cc but they seemed to work great. I had issues with throttle tip in where the car didn't want to boost but that was only for 1-2 seconds during tip in, once I was cruising or WOT it pulled hard within AFR. I figured it was just with my tune as I never dialed it in.

 

[Sjd6795]

Clean up the used valves and lap them in with compound to see if the seal is good and in the middle of the valve when you get to that point. We do ours. Supertech blue viton valve stem seals BTW.

How do these look? I didn't see much of a difference between the supertech and these GSC ones. The GSC ones come in a 16 pack for both intake and exhaust side so that's why I'm leaning towards that.

https://www.extremepsi.com/store/Fe...1990-1999-EVOUTION-VIII-and-IX-2003-2006.html
https://www.extremepsi.com/store/Fe...1990-1999-EVOUTION-VIII-and-IX-2003-2006.html
https://www.extremepsi.com/store/GS...e-90-99-and-Evolution-8-9.html?keep_https=yes

 

[1990TSIAWDTALON]

Those seals are fine. I get them on ebay even. As long as they are blue viton.
I run Supertech valves that are nitrided.
Check into a seal install tool. Its plastic and not expensive and makes the seal install a breeze, like this one...... https://www.euroexportinc.com/valve-seal-installation-tool-mitsubishi-4g63/
The valves that you reference are good too, I've never ran them personally is all.

 

[Sjd6795]

Those seals are fine. I get them on ebay even. As long as they are blue viton.
I run Supertech valves that are nitrided.
Check into a seal install tool. Its plastic and not expensive and makes the seal install a breeze, like this one...... https://www.euroexportinc.com/valve-seal-installation-tool-mitsubishi-4g63/
The valves that you reference are good too, I've never ran them personally is all.

Awesome well I just placed the order for the valves and seals. I also decided to order some BC 268/272 cams as well.