Hmmm,
Not sure I'm wholly qualified to answer your post, Mick, but I'll have a go:
It's often a tall order to work out exactly what's happened to the car whilst in the Orient, did it come with any paperwork/history? - even brand names may help narrow things down, if the rest of the blurb is in Japanese (actually there is a chap on 300zx.co.uk that speaks and reads Japanese, so this may be of use <img src="http://www.zclub.net/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt='
'> ). Some pointers, however:
1. If you've got an Electronic Valve Controller (also known as boost controller), it's almost certain that the car has been "chipped", if not, you may have problems on the higher settings, since higher boost needs richer fuelling to avoid detonation which can lead to meltdown <img src="http://www.zclub.net/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'>
2. You should be able to tell if your ECU has been replaced/chipped. It resides under a wooden panel, beneath the passenger footwell carpet. Remove the lid and see what's inside. Often the ECU is changed as a whole, and maybe badged up as a replacement (for example mine says "Mine's" which is a Jap tuning company). If not, then the ECU chip itself is often swapped out of the PCB, in which case it will be "socketed". This means that the original chip has been de-soldered and a socket installed for a replacement chip to be plugged into. The chip may be branded .. common ones are JWT and SE (unlikely on a J-spec car).
3. An aftermarket boost gauge is another sure sign that the boost has been upped, since the standard one is notorioulsy "wafty" and in any case won't read high enough for seriously tweeked boost. Standard boost is 0.6 bar, if you're reading higher than that, then you've got modifications to that area.
4. To find out the true bhp, you need to get the car dyno'd - in my experience, there is no accurate rule of thumb to guess bhp, simply by level of tuning accessories, there's more to it than that.
5. I suggest that you get the car into an expert if you really want to know what's been done. For example, in serious applications, the car will likely to have uprated intercoolers/injectors etc, which are not really apparent without some serious investigation.
6. Could I also suggest that as well as the help you'll get here, you may also want to seek advice on www.300zx.co.uk, where modding cars is a way of life! Also, check out www.300zx.org.uk for more info about tuning Z32s.
I don't know what you drove before, but I always think these cars go like a rocket in standard guise!!
Do you have any pictures of the car, I'd love to have a look!
Sounds like you may have a beauty!! <img src="http://www.zclub.net/iB_html/non-cgi/emoticons/biggrin.gif" border="0" valign="absmiddle" alt='
'> <img src="http://www.zclub.net/iB_html/non-cgi/emoticons/biggrin.gif" border="0" valign="absmiddle" alt='
'>
Hope this helps,
CheerZ,
JB.
