Quoting TomN:
To say your looking to build a motor to hold 30psi is meaningless.
30psi on one turbo could be 300hp while on another 800hp.
What's your actual hp goal? You build a car around a desired hp goal not psi.
Also what do you plan to use the car for?
MUCH RESPECT FOR KEEPING IT REAL, TOM.
Lord Athey, don't take such questions the wrong way, boss. Those of us who actually have to save up to do this sort of thing need to be super vigilant about our planning in order to get the most value for our money. 30psi is good in that it's a specific, measurable goal, but it's not very reflective of how you use the car. You've mentioned weekend plaything that you take the track once in a while, but you've also mentioned DD duty. How much time do you expect to have your foot in it all the way out to 30psi? How much time at output levels well below that? What's a 30psi car like at 15psi? See what we're getting at?
I'd offer that the stock bottom end, properly assembled and maintained, and competently tuned, has been known to deliver 400hp for almost a decade, now, which is more than enough to blow the doors off just about ANYTHING you come across on the street without a roll cage. So how about trying something truly epic - optimizing a bunch of carefully selected OEM bits so that, even if you're just running to McDonalds, the car puts a smile on your face. There are plenty of 600hp-capable cars out there with only 200hp-capable drivers behind the wheel talking big numbers on the internet, but these cars (and their DSM counterparts) got to be as popular as they are because guys were nickel-and-diming their way to big power and fast times on minimal mods.
To give you some ideas, here's what I'm planning to do for my race engine build and why. (For an actual, caged, race car.)
BOTTOM END:
+ 2G piston/1G rod combo (increased compression ratio = better off-boost, quicker spool, greater engine efficiency)
+ knife-edge/lighten crankshaft (reduced rotational mass = improved acceleration)
+ crank-scraper/baffled-pan (keeps oil in pan, mitigates risk of starvation under extended cornering)
+ balanced at LEAST to factory redline, but with a focus on 3000-6000rpm (where I hope to spend most of my time)
TOP END:
+ 1.8L head (further compression ratio gains, tip-in responsiveness, spool reduction, efficiency)
+ *mild* headwork, gasket-matching, port/bowl surfacing (increased efficiency, better fuel atomization)
+ Evo 8 cams (inexpensive "264/272" combo if I remember right, lighter weight, power is made in the head)
+ adjustable cam gears (fine tuning of hp/torque curves)
+ JDM Cyclone intake manifold (more low- to mid-range torque, improved turbo responsiveness)
+ exhaust manifold - maybe FP cast, Evo III? (improved turbo flow, responsiveness)
+ Evo III 16g (super responsive, should be a blast to max one of these out in an optimized chassis)
Then there's the usual intake, IC plumbing/size, and exhaust bits, an Evo 8 ECU to control it all, gearing, clutch, suspension, tire, brake, selections, but this is just what I'm thinking about right now. I don't have a specific boost pressure or horsepower or even torque target, but when it's done, it's going to be soundly in the middle of the pack - whether I'm drag racing, road racing, autoxing, or rallyxing - without sacrificing so much that I can't drive it to work or a race in a neighboring state.
Remember, for every 600awhp monster build you see, there is some guy sick of his car's sh*t when nobody's around.
Plan it. Build it. Drive it. JSB is no way to be.
