Head Work

[akhilleus]

I went to this shop that had a full machine set up. They could port and polish the head and intake/exhaust manifolds for like $800. Then they suggested having the head milled and that was $500. They also quoted piston installs @ $800 which i thought was low but they had a boring machine. These guys race nhra dragsters running 10's and 7's. But they are domestics so they might be screwin me on the price. Their labor rate is high $75/h. So these intalls took about 10hrs each. I am gonna look into this more and let u all know. I think that u could find a place that would charge $40/h on labor, $40/h on the machine. maybe $600 for the port and polish.

 

[mp3moose]

I got my piston in for 350. Just an FYI.

Moose

 

[twilightprotege]

head milled for $500???? way too much
port for $800...if they are doing the intake manifold at the same time...and they are good....probably about right. my port of the head is costing me $550usd

no idea about the piston installs though

 

[MikeBlueP5]

yeah to mill a head doesnt cost 500, on a FS engine we would probably charge somewhere around more like 50. Only reason being is because the cams would have to be pulled to have the valves closed so the machine doesnt cut them. regulare price on a four banger head is 20 bux, and 15 for a v8 or v6 each.

 

[twilightprotege]

when i get my head milled it's costing me $50aud - that's about $33usd...and they said they'll mill the head to whatever compression ratio i want, as long as the head can take it safely.

 

[akhilleus]

Yeah but figure in the labor to pull the head and remove the valve cover, intake manifold, exhaust manifold etc.. And then reinstall it. Also all these prices were individual not all together. But u are all right they are really expensive thats why i havent gone there for work. But is $350 realistic for the pistons? I have heard that it is normally more...

 

[twilightprotege]

arhhhh. i c. fairy nuff den....

 

[Kooldino]

kool-it might be possible to mill the head and get the amount of compression the pistons give, then again maybe not. I would have to pull the aera book and check the specs on what the minumum thickness of the head could be, then do the math to figure out what the compression would be after taking off X thousands of an inch.

I just mentioned the pistons because they would be super easy to put in while the head is off and it would give him something to do while the head is at the machine shop.

How would the pistons be so easy to swap out w/ the head off? The pistons are still attached to the rods, and don't clear the top of the "bottom end".

 

[Kooldino]

Twilight - thanks. How much power does it add?

All - careful w/ milling the head. Sounds like cheap power, but your engine may no longer be "non intereference"

 

[twilightprotege]

the difference between a 5 angle and 3 angle job in a car that makes 200whp....maybe 0.5whp more....it's only when you start getting into really high power engines and you want that last little bit of power....in a car that makes 500whp...then you're looking at another 3-5whp with a 5 angle over a 3 angle. it's mainly because of just how much air you're shoving into the engine. and for a racer, 5whp is a huge difference!!!

but anyway, for our cars, 5angle job is not required. save yourself the money and just get the 3 angle job and spend what you save on something else

 

[twilightprotege]

well guys i'll be getting my ported head back on thursday and will be installing it then....but one question i hope someone might know, is any gasket sealant required for the head and various other gaskets? i ask because the shop manual doesnt say so, but i just wanna double check...

maybe the stock mazda ones have the sealant chemical already on it...anyone know???

 

[MikeBlueP5]

shouldnt need any sealants for the HG, it will most likely be a multi layered steel gasket. It should have all the sealant on it when you get it.

 

[twilightprotege]

yeah i thought it would already have sealant on it from mazda. thanks. just need to get some grey rtv sealant now

 

[Subghetto]

Does anyone know how much the the p5 should be port and polished b/c I'am thinking of doing head work and I don't want them to make a black hole b/c since I don't think this can be fixed once it has been done and it will decrease peformance.

 

[twilightprotege]

mine is costing me about $900aud - that's about $650usd....plus you'll need new gaskets and depending on where you get them you need to add that in. mazda ones are expensive, but unfortunately the only ones available in australia