ok i was reading up on port and polishing on the head does this really give you a gain of horsepower or is it just for looks or to feel good? how does it work then it just smooths out the areas for the intake and the exhaust so it flows easier?
It's done mostly to increase flow and pumping efficiency at high rpms, but increases flow across the whole range. Like b said, you can really mess a head up if you open everything up too much.
Depends on the port job, the rest of the setup, etc You think a P&P on an anotherwise stock motor will make a huge difference? You can't just use blanket statements like that in relation to port work.
I have some idea of what I'm talking about, im not making "blatant" statements. A PnP on a stock motor won't make as much of a difference as a modified motor, of course not. But it will make a noticable difference depending on the car. Since most Hondas aren't exactly tuned for performance there will be enough of a difference where you can tell. Now if you had done it to my 944, which was tuned for performance from the factory (even though it wasn't much) it wouldn't see the gains that a Honda would if any. Please, If you feel it's so necassry to try and make your self look right at least do it properly. If I was wrong about something correct it, not try to make me look stupid for making a mistake. This statement says enough. If anyone is having a PnP done, it would be wise to have it done professionally.
When I said blanket, I ment blanket. Meaning making one statement that covers every situation. I have seen a dyno of a honda b-series, with nothing but a P&P job done by a very reputable company that barely gained 1-2whp throughout the powerband over stock. I can post the dyno if needed My intention was not to make you look wrong or stupid. Maybe you shouldn't take posts so seriously. If posting that port work on a stock motor does little to nothing prevents a few members from shelling out $800+ hoping to get 10+whp out of a P&P head, and pisses you off in the process, then I honestly don't care.
I'm not taking it that serious. But I really think that it would give more than 1-2 whp. It does a lot more to a modified engine, I agree. Please post that dyno, I'm not saying your wrong it just seems like to little of a gain. I think even with I/H/E it would make a more noticeable difference, which most people have already.
Unfortunetly the thread with the dyno, no longer has working links for the pictures themselves. However you can read the results and peoples impressions, which kinda sums up my thoughts. http://www.honda-tech.com/zerothread?id=815557
It also depends on what head you are doing work to. You can see a HUGE difference in port sizes between pr3 and pr4 stock heads, and although I agree with styleteg (don't know your real name, sorry) I will be hoping for a bit more than 2hp on my diy b18a pnp job, of course the rest of the engine won't be stock either. If it were a pr3 head, I wouldn't count on much.
<--- Ross, nice to meet ya Yeah you are definetly right, the port sizes are extremely different for different heads. Even between the B18A and B18B heads. However, I think honda does a pretty good job packaging the heads to the rest of the motor. In the case of the B18A specifically, the intake manifold/cams/etc are all geared towards a lower powerband range so it makes sense to keep the ports smaller. With out aftermarket cams I don't know how much better you could make it flow minus a valve-job. But this is just speculation for this specific B18A vs B case.
another ps, pr3 pistons and intake mani will also be installed. The pr3 intake has already been modified to fit the pr4 head btw mike's my name lol, right back at ya.