98 prelude H23A VTECH blue top swap, stage 3 ebay 4 puck clutch, ACT flywheel, P28 chipped and flashed, intake, 35 shot Nitrous express wet shot. 70K miles. I have been beating the dog $#!t out of this motor and finally ran into some issues. Vtech would not engage....it would get really loud and no power. Did a compression test and ended up with 180, 75, 180, 160. It ran fine and drove fine just zero power in vtech. Pulled my head clearly one valve was almost white. Leak down test and the bowl drains almost immediately. So i figured id just build the head, thicker head gasket, ARP head studs, timing belt, manuel timing tensioner, valves, springs and retainers, cams, cam gears, IM, TB, full AEM fuel system, 1000CC injectors, water pump, maybe shim my oil pump, header, MSD cap/rotor/coil/10.2MM wires, nitrous window switch etc. 75 shot and tune. Probably missing a few things but you get the idea. May as well build my head since its off and have to replace some things anyway. So my question is on stock block 75 shot tuned....what cams, valves, springs etc. Would be best?? Stage 1,2,3?? Lb springs?? Valves?? On nitrous!!! I need to order stuff now before i spend my money. Experience and facts please, i can spend weeks searching and get thousands of he said she said....please facts, proof, and experience...thanks. -chris

 

Be careful with aftermarket cams. H23A engines are known to have piston-to-valve contact when using aftermarket cams because of the factory piston design. The valve reliefs are inadequate. There is info about it in the "H23A blue top mystery thread" here. I would stay at a 75 shot or below, and tune conservatively. H series like to pop ringlands and as a bonus the H23A is capable of making too much torque for it's own good which can lead to a broken connecting rod pretty quickly when using power adders.

 

Im sticking with stock cams until i finish a built block next year...thanks

 

Probably a good idea. There are strengthened Type-S pistons that just drop in with your stock H23A rods available on eBay. They are made from a better alloy and will better withstand nitrous or boost. They also provide a slight bump in compression and eliminate the valve relief issue. Those are an option if you're comfortable doing a piston swap and re-ringing the engine.