dirvin7588

Ok so I have D15b with a Y8 head, first for now imt thinking about just throwing a B series TB on it and a OBX manifold. Any opinions on the OBX manis??? But I'm looking for springs and valves for my head manily because I want to switch them cam. Was thinking zex cuz I he'd they're the best from idle to 6800 rpm. If I'm wrong please correct me. But after building the head I'm goin to get either Skunk2 or Edlebroke intake mani, AEM fuel reail and FPR and prob bigger injectors, I'm running all motor and looking for high compressions pistions too! If someone could steer me in the right directions id appreciate it. A6 pistions are 11.5:1 correct?? Will the fit he d15 block??? THANKS IN ADVANCED!!

NotAJDMFanBoy

You're fighting an uphill battle. You're never going to make good power on an NA D series. I would suggest looking at forced induction. If you really want to make power on a D series, here's what you should do.
The D16Y8 intake manifold flows pretty well. It is a small step up from the D16Z6/D15B intake manifold you have. If you insist on aftermarket, get one with longer runners. You can't afford to lose all your low end on a D series. They're already pretty gutless.

Your valves are fine. You could get a valve job and have them cut or get new OEM or OEM style valves. I would suggest Supertech for any valvetrain since it's good quality stuff and it's cheaper than a lot of the big names.

Cams, I know nothing about. At least get something sold as a stage 2 or something that says it requires upgraded valvetrain.

Your OEM fuel rail, fuel pressure regulator and injectors are plenty. You have 240cc injectors from the factory and you can make over 200hp on them safely. Plus, they will idle perfect and don't have to change any wiring or anything. You don't gain power from upgrading injectors, you only have to upgrade fuel system parts when you are going to make too much for the system to reliably support. Don't waste the money.

The pistons will make a different compression ratio based on the block's deck height, the crank, rods and the head as well as the head gasket and how much is surfaced or milled off the head or block. This is a simple tool to give an idea of what different parts will make. http://www.zealautowerks.com/dseries.html There are some flaws and any piston combination that isn't well known to work should be clayed to check for interference before final assembly.

All D series pistons are the same diameter.

N/A*GSR

Not trying to discourage you from your build, but if I was going to put that much into a D series I would go forced induction or a B swap. I've owned a D series and now own a b18c1, the difference is night and day. If you do happen to look for a turbo kit instead or just need D16 parts check out www.go-autoworks.com, the owner Greg had a turbo D16 in the 10s he could help you out a ton.