motor build?

mazdaspeedp

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2003.5 Mazdaspeed Protege
so i was thinking of building my engine soon and wanted some input so ive been told i need to rebalace the crank,replace headstuds, do a main cap hone and a 3 angle valve job also replace rods and pistons with forged ones. So is all this necessary or am i able to skip out on a couple of these steps like say not do the 3 angle valve job.?
any info would be appreciated
-thanks -Andrew
 
You can skip whatever you like. But since you have the motor apart, replace as much things as you can with quality parts and you will be better off in the long run. 3 angle valve job may help but most people go with a slight P&P with matched ports. You will find what you want, just look for it some more.
 
DONT CUT CORNERS! We all know this stuff gets very expensive, but cutting corners will most likely cost you more $$$ down the road plus additional down time.
 
i know i dont plan on cutting corners i just didnt really think doing the valve job was really necessary i talked to a few mechanics and they said it didnt really need to be done. Any suggestions on other parts to add in while im gonna be doing this anyone here ran the k1 stroker crank?
 
The crank is forged, as long as you have never spun a bearing i would keep it. Just spec it out and im sure you will be fine. That and a 3 angle valve job arent a must. at least get a valve seal kit.
 
If you think you might want an upgrade I say do it now! If you put the motor back together and regret something later. As the valve job goes, I know a few engine builders who say you can get 20hp out of a chevy 350. While it might not give you big gains it will help scavanging of air. The inside of the engine is were the power comes from, everylittle bit helps and you will be making your engine more effecient.
 
ya i see what your saying its just that a few mechanics said that the valve job is gonna get expensive for not that big of gains. They were also saying that it will weaken the valves. I dont plan on skipping out on important things just trying to not go crazy with max cost if its not necessary. So far i plan on getting a build kit with rods ad pistons forged also all the gaskets and new head studs. i will get the crank balanced and do the cylinder hone and main cap hone. just trying to figure out exactly what i need to do a good job to support decent horsepower probabley around 320whp if i can using a gt2871r turbo
 
It should not hurt the valves all they are doing is cutting into the seat so instead of a round surface you get three angles to maximize flow and velocity. This is a mod that will increase your gains when you increase flow and velocity as well such as more boost so if your gonna try and make some power this is something i would personally do.
 
Just do the money to HP ratio. What are they quoting you on a 3AVJ? Been looking into getting my head reworked while the bottom end is getting built.
 
for the head, PnP, 3AVJ, decked surfaces, new seals to start.
for the block, decked surfaces, forged internals, balancing is a good idea, cylinder hone (or bore), bearings, gaskets, etc. ARP head and main studs.

a real budget build is tear down the old motor and replace with forged. youre better off finding a balance in-between top-of-the-line and budget... you can save a few dollars here and there with OEM vs. race bearings or some fasteners, you can minimize head work, but you only want to pull the motor once so best do it right the first time.
 
ok so im makin a list
1.Pnp
2.Build kit with rods, pistons, bearings,gaskets,headstuds
3.Balance crank
4.main cap hone
5.new valve kit/ 3 avj
 
if u can get the head flowed while your doing this stuff you can get a potential horsepower number by doing .25xcfm at 100% effeciancy but since we use turbos we can hit about 120% just something you could get done if your shop has a flowbench
 
ok im not sure what that is exactley the machine shop would get the head flowed or what do you mean
 
a machine shop may have a flow bench wich pretty much just meens you put ur head on a block and flow air throuugh it. Flow is rated in cfm or cubic feet per minute. An engine builder can use this to tell a customer wether or not the engine is gonna make the power he wants. Its a building tool if you want it to be fully badass but isnt something that has to be done.
 
oh ok cool ill look into that and see what the machine shop says and i will probabley get it done depending how much more there gonna charge
 
Yeah i have no idea how much it could be. You can use the way the port flow as a tuning tool for porting the head.
 
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