I was under the assumption that these need to be tuned some how on a rolling road or some such?
Depends, you can do a fairly good job yourself if you have the knowledge. I think EMB is easy to tune yourself and people get decent power from it. DIY setup wouldn't exactly need any fabbing if you have £2k to spend, and you will be able to get 200-250bhp. My list would be:
Begi cast manifold and downpipe (
www.bellengineering.net)
T25/T28 from an s13/14 200sx (can get a rebuild kit ~£50, good idea to do)
Universal intercooler mx5 kit (
www.universal-intercoolers.co.uk)
Emanage Blue
Toyota Supra 305cc injectors
LC-1 wideband
Boost guage
Depending on the power you would like then there are a few other things you will need.
2.5" exhaust system
AFPR (get the begi one)
The AFPR gets around the maximum that the EMB allows a good idle on the mx5 for. So as the boost increases, so does the fuel pressure, this way you can safely run 200bhp at 80% duty cycle and 55psi fuel rail pressure. At a push you can do 250bhp, but that is the limit for the EMB really, as that will be 85% duty cycle with 75psi fuel rail pressure. People run higher, but I like the idea of not pushing things too hard.
The exhaust system will get more power and speed up the spool. That covers the major parts, though I haven't covered all the details there.
