Top end rebuild.

[90blue]

Porting is not something I would consider unless I intended to go FI.
If so then check here http://www.miataturbo.net (only read, do not post, far to rabid)

There is more horse power to be made with the 99 head.
There is more torque from the VVT 01-05 non MS head. Bell Williams is racing and uses a VVT head with a square top intake manifold, or at least did, successfully.
For parts and opinions check out 949 racing http://949racing.com/engine.aspx
My 2c

[— kung fu jesus —]

Found a head at the local bone yard. It's on a 94 Miata with a 1.8L engine. They only want $102.00 for it. All I have to do is pull the Intake off and remove the head bolts to get it off. Next step is finding an automotive machine shop that can shave and port it.

If you are having a machine shop do that, you should also have them check the springs and valves at a minimum. New valve guides are a must.

[NobleRogue]

I appreciate all of the advice on getting a 99-02 head. I would have gotten one today but the bone yard had only two Miatas. A 92 and a 94. The local Miata bone yard wants $500- $600 for them If they even have them in stock. And I hate buying used parts online. You never know what you are going to get. Most of what you find are mislabeled or give to broad of a description. I was looking at heads last night and you wouldn't believe... "maybe you would"... how many were listed as "1.8 L Head for 1990-2000 Miata" and the CPS was usually on the wrong side to be for a 1.8 L. . When sourcing parts, you need a lot of patience or you may end up giving yourself an aneurysm. lol.

If you are having a machine shop do that, you should also have them check the springs and valves at a minimum. New valve guides are a must.

Thank you kfj. I was already intending to replace all old parts with new including the guides. But I appreciate the advice. Please don't ever assume that I already know something cause chances are, I don't. And just to prove my point, at the risk of looking like an idiot, I must ask. What do you mean by "check the springs and valves at a minimum"?

[— kung fu jesus —]

Sometimes you don't need all new parts. The factory valve springs have specific measurements and allowed variances. The same goes for their spring rates. They should be able to compress them to test their effectiveness.

Likewise, valves can be measured and their stems checked to be true. If they are good, that is money saved or spent on other tricks, like valve cuts, etc.

[NobleRogue]

I was thinking about using thees. www.flyinmiata.com/valve-spring-kit.html .. http://www.mossmiata.com/Shop/ViewPr...eIndexID=77140 .. and cams from HKS intake and exhaust are $355.00 each. The Cams may have to wait though because of their price.

[— kung fu jesus —]

Feh. I would wait until you get cams. Otherwise, unless you are going for a monster head shave, you only need one.

At this point, too, I have to point out a good BP4 motor is about 1000-1200. That's 140hp, bolt in.

[NobleRogue]

1. BP4???

2. Would that be the intake or the exhaust side if I go with only one cam.

3. How much would you recommend I shave? I do intend to keep this as a daily driver, so I'm not trying to completely ruin its reliability. Maybe just bring it up to 10:1.

[— kung fu jesus —]

BP4W, '99-00 engine.

Intake, stock cam.

I don't know the max amount that head can be shaved. The internetz should have some specs out there. These are all things you need to research, including a shop that knows enough about the head to do the work. The truth is out there.