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My wrc replica build is still active.
I saved enough money to build engine and turbocharger.
My goal is around 400~450whp.

But first, I am going to get 2005~2007 focus ST and build engine and install hyper single clutch.

If compression test shows a good result, I will stick with stock bore 87.50 and compression ratio will be 11.04:1 with Wiseco according to CFM.
Do you all think 11.04:1 is enough to support 400whp+?

Or go with Supertech 12.51:1?
And which connecting rod would you recommend?
Eagle forged H-beam or Crower Billet?

What else is recommended? have cylinder head ported?
 

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Run the 11.04:1 compression, just be sure to soften the sharp points in the pistons and chambers. If you have the patience for it, buff the combustion chambers with a fine crossbuff and apply a layer of emery rouge to polish the chambers and help prevent carbon buildup. This can take a few hours of time to do properly but is worth it. With a stock 2.3L head, I'd run a set of cams in the 218/212 @ .050" range with about .380 lift and a 115-117 LSA on a 112-114 ICL. You'll need to keep dynamic pressure down at lower rpm and increase velocity at higher rpm with this build. Start out with the spark advance in the single digits and slowly creep up on it. I like NGK recessed tip plugs (BR7) with the high compression turbo build to put the spark just a tad shallower in the chamber.

Since you're only looking for 400-450whp, the Eagle H-beam rods will be sufficient. The K1 rods will work fine as well. Be sure to use ARP head, rod, and main studs. ARP's torque recommendations for head studs is 60lb-ft but I'd run it up a little higher around 70-75lb-ft in 3 sequences to help prevent the head from lifting. Open the ring gaps a bit more with boost to around .018 for the 1st ring, .024 for the 2nd ring, and .030 for the oil ring. This will allow more room for expansion with the higher cylinder pressures and heat.
 

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I am all for compression and boost but for your goals there is no need for 11:1, somewhere closer to 10 should be fine. Top speed did 450 on a stock 2.0 with Cosworth IM without much boost maybe 20 lbs. It scattered on the dyno but that just goes to show you don't need to get crazy to make power. some stronger pistons rods, arp hardware and probably valve springs is all that is required.
 
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