I'll be running a jdm b18c1 with a .120 Cometic headgasket (9.6:1 cr) with Arp headstuds and rod bolts. I'm looking to get 325whp with a Garrett t3/t4 57 trim .50 coldside .63 hotside and dsm 450's.

 

Its all in the hands of your tuner, should be possible. What pistons are you using to get the lower CR? I would use a set of forged pistons and rods if your not already.

 

I'm on a budget build, the 3mm headgasket will lower my 10.6:1 to 9.6:1. I see stock b18c1 doing 285 at the wheels, so I figured that this set up should be good for a few more whp.

 

Tuning is key. I've seen several people run 300 whp on a stock block, without sacrificing reliability. There have been a few that made 400 whp, but none of those engines lasted very long.

Using a thicker head gasket isn't the best way to lower compression, you might have a problem cracking the gasket under boost. With a good tuner, you can use an OEM headgasket and keep your CR at 10.6:1 without problems.

 

Ummm.... no, it's not set up good for 325whp. It may be set up bad for 325, but not good. ARP headstuds are worthless on your setup because stretching a headbolt is the last thing that'll happen. Your rods/bearings are going to be first on the list of broken parts.

 

not at that power level. the injectors are the limiting factor in that setup.

 

Actually they are worth it, because if you have to pull the head of for any other reason oem headstuds are only supposed to be used once because they stretch when the head is torqued down. thats about $50-$60. everytime you take the head off when using oem headstuds. ARP's are designed not to stretch and can be used over and over again!