how should i machine the HEAD?

[quansta]

i want to go to a machine shop a get my head polished and maybe ported so the inside is smooth for the intake and exhast and i would also like to maybe shave the bottom of the head for a slightly higher compression. what i am confused about is what exactally should i do to the head and how much to machine it for the most optimun performance and horse power. If anyone has any suggestions i would greatly appreciate it.

[240ZX]

quansta,

Your question is just to general to provide you an answer. You might want to do is do a little research on this site and other Z car sites. There are forums that discuss technical issues on just about anything you can imagine, regarding setup and modifications to the Z car. Be aware, in order for someone to provide you with a good answer to your question, they would need to know the details of your engine, is it stock, any internal modification like a hotter cam, what's your induction system, etc., etc. We see these questions all the time here. So, spend a little time and do some homework. It's always a good education and you will discover that with the knowledge you gain you will be answering alot of your own questions. Also, when you do get ready to have your head worked on, take it to a shop who is familiar with the Z motors and have the knowledge and experience of doing proper porting/polishing and or decking jobs.

To give you an idea of cost, you can be looking at about $850.00. I'm sure there are shops that will do it for less or for more but, it's not a cheap exercise if you want a good job done.

[1975yellowBSPZ]

A quick conversation with Rebello Racing or a copy of "how to mod ify your Nissan OHC engine" would be a good place to start.

[MicksZ]

I think its all about the resources you have/want to purchase.

Lucky for me my father does race-application head work here in AUS, but he doesnt do big valve conversions. He gets them done off-site, but he does have all the usual die-grinders etc for port n' polish jobs.

I own a 1200 coupe which was my first car, and I attacked (yes, the better word being attacked) the head on it to match port the extractors and weber manifold. It was a hard slog, but with the right advice and good tools, i didnt find it a hugely hard task - a steady hand is the key and take your time.

Of course having dad's tools was an advantage, but i think if you can't afford a $500 port n' polish job, and you are after a little bit of performance - get your hands on an old cyl. head, (and if you have a compressor) buy a grinding-tool, some good end pieces, and have a go!

[beandip]

As was stated quite well by 240ZX , we need more information. It might even be better to replace the head for one with larger valves so that is already done. Here is a web page that might help www.geocities.com/zgarage2001/engine.html have a look. where do you live ? You left that blank . I know of a great place here in Portland I hope this helps , at the vary least you will find some great information at Brians Garage site. .:classic: