Rebuild good 99 head, or just put it on?
 

I was just about to go into the garage and bolt my 99 head to my freshly built bottom end. Then I got a little paranoid about whether I am taking the appropriate course. How many of you have stuck a good used head on a freshly built motor? Should I pay $200 to have the head rebuilt or can I comfortably put it on as is?

I have really reached the point where I don't want to continue spending money just to spend it. Sure, everyone would ideally work from all new parts if money were no object.

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Id clean up the valves and the exhaust ports a little bit.

What is the tool of choice for this job? Just sand paper, or a light wire wheel that fits on a power drill?

I clean my exhaust ports with a dremel using a sanding drum first then a finer grit/ wire mesh stuff/ then finish it with high speed wire wheel to give it a nice shine.

As for the combustion chamber id put some laquer thinner on the chambers and work it out with a brush. Although i have never cleaned up this area so maybe someone else will chime in

I have installed a good used head on a fresh motor although I do an old trick to clean everything after break-in. I do not know if you have heard this before but I drain out about a quart of used oil and then pour that same amount with transmission fluid. Call me ghetto or whatever, I drive the car with 3 quarts of engine oil and one quart of transmission fluid more or less for a few days (maybe redlining it a few quick times, nothing crazy). Then dump out the oil and you will see how dirty it comes out. Transmission fluid cleans up all that gold brownish crap you see in the cylinder head.

Anyway, I learned to remove the valves and how to overhaul the whole deal, it is not that difficult, but is VERY time consuming.

I think that for $200.00 is a mega deal on a cylinder head rebuilt, the peace of mind is priceless. IMO, go for it, pay the 200 and call it a day, no more worries. Nothing worst than 5,000 down the road you have to open everything again.

Do understand the spending the "unnecessary" money, but cannot picture having all new bottom end and forget about cylinder head where all the magic happens.

Dont know if it makes you feel any better, but when I used to live in California I was charged $125.00 for only cleaning the cylinder head AND I removed and installed the valves myself, 200 go for it, super good deal.

A machine shop will dye it to check for any cracks, sand blast it and will look spanking clean. You can ask for a very mild resurfacing, test that it is not warped, the valve seals cost around $5.00 each the most.

On a side note:

Look at exhaust port #3, it has too much oil and looks shinny as if it is leaking from the valves as all chambers look the same.

I'd agree; $200 would be a good deal. That head looks a little rough. What's another $200? At minimum, it needed a serious cleaning a valve job anyway.

The 99 head I bought to put on my fresh bottom end looked much better than that one, and I had it built. At least have a machine shop verify it is a good head, check for warpage, valve clearance, etc. Its good money to spend.

Thanks, I'll drop it off tomorrow. I don't want to chance it leaking after i get everything installed. I'd feel pretty stupid. I thought the guy said it was $200 for cleaning and 3 angle valve job and cleaning up the bowls. He said it was that much because of the shims he had to deal with.

That's a good price for the work. I'd bet the thing is in need of a valve job. You also don't know how the head was removed; they can and do warp if you don't loosen the hardware in stages, so it's good to get it checked.

You could also take this opportunity to install back cut valves on the intake side. Yeah, it's a slippery slope, but that's a mod that helps a good bit with spool. I kind of prefer non cut valves on the exh side because they're stronger.

I'll ask what it will cost to back cut the intake valves. Money got tight on my build real quick. At Christmas a hell of a deal came up for the exact hardwood my wife and I wanted for the living room. 60% off so I scooped it up. Then a week ago I refinanced my house. I feel like I'm hemorrhaging money. Now I really want to push to get the miata project back on track. I was supposed to be installing a motor of Christmas, not hardwood flooring.

The the intake and exhaust valves all look dry, check the lash at .003-.006 I and .005-.008, then bolt it on and go.

Since you are going against the grain on this one. Why do you feel so confident in me not having the head rebuilt if the lash checks out? I would have expected you to be one of the first "have it rebuilt" crowd.

I should also mention that this head just came out of the box after sitting on my shelf for 6 months

If you are going to use the same lifters, get a big bucket that can have a lid and fill it up with transmission oil, a glove if possible and pumped them one by one in the oil.

The way that I do it is dip the lifter with the hole looking up so it fills up completely, then take it out of the oil and flush all of it out (repeat as necessary, usually 4 to 5 times on each one). Do this on each one of them, you will see how much crap is going to come out. Once you do that to all of them filled them up completely and let them rest for a day or so to soften any left over junk and start all over like in the beginning.

There is a way to open them up one by one, but at least for me it was very difficult. Just grab the middle of the lifter and pull it out. Like I said the center section is very smooth and is very difficult to make it come out. I have seen it done, but I gave up and prefer the other method.

At least me, whenever the cylinder head is going to be out for long periods of time I take all the lifters out and store them in a jar or bowl filled with transmission oil.

After I wrote all the above, I am not sure if your lifters are solid or hydraulic...

It's a 99 head, they're solid... so disregard the "pumping up lifters".

Have it rebuilt... you'll thank yourself later.

I'm going to drop my head off today. I've got a head gasket set that came from the engine builder. It looks like the cam seals and valve stem seals are the same part number for 97 and 99. Will the head guy have everything he needs with the 94-97 head gasket set? No sense in paying for it twice if I already have it.

Total price ended up being $320 for rebuild (I provided valve and cam seals) 3 angle valve job, and back cut intake/exhaust.

Is this a good price for this work?

It's about $60 more than I originally thought it was going to be.

The first time I stopped by he said $200 for the rebuild and then when I dropped it off he said $60 for the back cut.

I bet I was mistaken and the rebuild did not include 3 angle valve job.

I won't bother asking about the discrepancy if it's a good price. I don't mind paying for quality work if it's worth it. I don't want to insult the guy.

I think its a good price. mine was a bit more, but I had oversized valves installed.

I would gladly pay $320 for that work. The gains from the valve job alone would be worth it.

Make sure is a four layer metal head gasket, not that cheapo Felpro cardboard crap.

Its a mega good deal, I cant wait til you post pics of the overhauled CH, its going to be sweet.

I will add pics to my build thread tomorrow.

The gaskets are a brand I haven't heard of, but engine place is reputable. I'm assuming they are good. I just brought the box in: ERISTIC , indeed, the head gasket is 4 layer metal :)