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Head Rebuild

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TimF

10+ Year Contributor
823
5
Mar 14, 2011
Aurora, Illinois
I know this should be in another subject, but i want it more for a hang out convo then a info session i guess. I was planning on buying a cheap head for a rebuild, kinda like a do it my self thing. Im not sure what im getting my self into thoROFL:D I have never attepted this in my life. The only mech experience I really have is that im that guy everybody goes to for simple fixes on there car:hellyeah: I figured that if I find a cheap one, like a craigslist one I was looking at for 50 cause its has missing and bent valves, Just mess with it and if I ruin it oh well:rolleyes: There is a 95gs-t in the junkyard by me that I would take parts(like those valves). The thing that motivates me to do this was that I was watching one of those car shows a few days ago and they did the whole port and polish head thing and really cleaned out all the gunk build up and my moms boyfriend told me that I should do that to my talon:coy:
 
Instead of reposting I am going to edit this with more question that I have. I pretty much have a compltete head. I still need a thermostate housing(easy to find) Adj cam gears, and a CAS. I have all the internals and im going to use 272's on a evoIII 16g.

my first question is what type of cam gears?
fidanza seem to be the cheapest (other than no name ebay gears) but i read they have a tendency to slip, and the bolts strip
On top of that there is AEM which seemed reasonable priced, unorthadox, that someone is selling local for 100$ used, BC, HKS (which are nice but expensive)

I also have a question about CAS. from what I seen there are green tops, silver tops, and black tops, and I am wondering what is the difference and what one is the best
 
I've always rebuilt my own heads in the past- and considering the luck I had with a vendor earlier this year, I'll be rebuilding my own heads in the future as well. Sucks when the one time you venture away from what you know will work ends up leaving a bad taste in your mouth.

Now I don't have the ability to replace guides or machine valve seats- but I can remove and media-blast all of the valves, degrease the entire head, deck the surface with a longboard and 600G wet paper, seat the valves back in using lapping compound, and install new seals. It's not really that hard, just time-consuming.


Here's the head I rebuilt for the 1G that now belongs to my girlfriend- this head was rebuilt along with the engine at 172K, and the car now has 212K.

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Not sure why but I never got a pic of the assembled head, but that gives you an idea on before/after the degreasing.


I also rebuilt the head on my ex's old Sunfire at 150K. The head I removed had bad exhaust valve guides and for the price it was easier for me to buy a good used head from a local salvage yard and rebuild it myself instead of paying a machine shop to change the guides.

This head remained on the car until she sold it with roughly 185K on the clock. I must say it was MUCH easier working on an 8-valve head....took about half the time. :p

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I figured that. I am just stuck at my choise for cam gears and CAS. I have everything else.

also how do you lapping compund I am not familiar with that
 
Lapping compound is product, not an action. The action is "lapping the valves."

Why bother with cam gears? At this stage it's likely you won't need them. And you should stick with the stock CAS.

Here is my head:
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Lapping compound is product, not an action. The action is "lapping the valves."

Why bother with cam gears? At this stage it's likely you won't need them. And you should stick with the stock CAS.

Here is my head:
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also how do you lapping compund I am not familiar with that
It's like a super-gritty water-based rubbing compound. You put a little on the base of the valve which contacts the seat, then use a lapping tool to spin the valve a few times in a rapid back-and-forth motion. You then pull the valve out and look to verify that there's a nice cut "line" around the entire radius of both the valve and the seat in the head. If there are gaps in the line, either the valve or seat are damaged and will need to be replaced.
 
It's like a super-gritty water-based rubbing compound. You put a little on the base of the valve which contacts the seat, then use a lapping tool to spin the valve a few times in a rapid back-and-forth motion. You then pull the valve out and look to verify that there's a nice cut "line" around the entire radius of both the valve and the seat in the head. If there are gaps in the line, either the valve or seat are damaged and will need to be replaced.

I used a drill :D. Just spin one way for about 45 second, then the other way for 45 second then back and forth by hand a few times. Worked like a charm.

Of course this was just a stock rebuild. I took my head in the above picture to SIM for a 3-angle valve job.
 
Lapping compound is product, not an action. The action is "lapping the valves."

Why bother with cam gears? At this stage it's likely you won't need them. And you should stick with the stock CAS.

I am doing a complete build. I figured that adjustable cam gears would come in handy considering that everthing else is going to be upgraded, except the valves, and could help me squeeze out more power. What would be stock CAS thats what I am confused about to? Im going to swap motors so I need to get the whole motor together. So should I just go with the same CAS color on stock engine now?

The head I bought already had a 3 angle valve job and was only used for a short amount of time before the owner parted the car out

here is the head as it sit now, stock springs retainers and valves (im swapping in FP springs and titanium retainers)
 

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Google jafromobile "cylinder head 105. valve job basics" sorry don't know how to put the link here. Shows a pretty detailed lapping of the valves did mine by watching this. and it is a "permatex" brand and is called "valve grinding compound" comes in a 85g tube. hope this helps video will
 
how do you clean off that gunk in the combustion chamber were the valves are, mine is a bit dirty. I tried parts cleaner with a wire brush (hand held) and it did not seem to remove any of it.


nevermind it show me in that video

When I bought the head the former owner just threw the rockers, lifters and cam caps in a bag with fresh oil. I watched all his videos and he said to keep them in order, is it going to be that big of a deal because I am going to have no idea what valve they came from
 
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I picked up a black top cas from the boneyard for 20$
 
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