For those who might be interested in the details, this is just a stock head for the D16A6 on my CRX. I've been needing to replace my head gasket and figured I'd swap out a head while I'm at it. So I picked up a spare head and went to work.
Originally, a friend whom has the professional experience, tools, and flow bench access, was going to do the work...but scheduling wasn't going to work out. So I asked for guidance and went to work myself. As you can see, the exhaust ports and combustion chambers have been polished. The intake ports on the other hand are not. The idea is you want the air to 'swirl' into the cylinder. The basic idea is that an engine is a large air pump, and the more efficiently you can get the air to flow, the more power it can produce.
As an addition to the head work, all the ports are port-matched to additional intake and exhaust manifolds to better improve the air flow.
I guess we'll see how it all works out. I'm told I will definitely notice an improvement in throttle response and will see marginal power gains. I have a tuneable PM6 ECU so I can get it all to run efficiently. I know I won't see the kind of gains I would get from a motor swap, but this will be a great learning experience for when a swap does happen.
Just in case any of you have never seen a stock intake/exhaust ports, here was what my starting point looked like...
The surface of an exhaust port is the same as this intake port. The combustion chamber surfaces aren't all that smooth either. There are seams in the ports that are left from the casting process, and smoothing those out while not taking away too much material, or disfiguring the port, was probably the hardest part. This project was not easy and I wouldn't recommend it for the novice tuner. I'm sure it would have been a lot easier, and faster, if I had all the right tools. Quite frankly, next time I'd rather have the pro's do it, considering the amount of time I spent. The experience though has helped me appreciate the meticulous preparation and execution it takes to do this kind of work. :happysad: