holy crap man.
okay... first of all, be prepared to spend LOTS of $. prolly around say, 25Gs to do both cars at least, and I think that's a generous guestimate.
Like NRcooled said, what country you're in makes all the difference in the world for what setup to go with, and what's available to you.
1) when u say s13, u mean, silvia? 240sx? 180sx? 200sx?
s14, u mean 240sx? silvia? or 200sx?
2) building a sil80, for s13 chassis means getting a kit, many places do these... if you're in the US, check with Grumpy at www.mckinneymotorsports.com he's the man.
3) 4-500whp?! I'm assuming neither car will be meant for daily driving then? You're looking at having a fully built engine for KA, and at least some upgraded internals for SR
I think you need to give us more to go on detail-wise for more help to come <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt='
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