OBD - On-Board Diagnostics ... OBD-0 is an ECU-equipped vehicle with the capability to "tune-on-the-fly" or work in optimum fashion according to the operating conditions; OBD-I is an ECU-equipped vehicle as above, and features a diagnostic plug for accessing trouble codes and uses enhanced and simplified operations; OBD-II is the newest (1996-newer) version of the OBD system with a light (in most cases) and diagnostic port for reading AND writing to the ECU, and features comprehensive diagnostics capability as well as flash-encryption on certain models.

I suppose I'll stick with the stock fuel injection and ignition for now, however in the future I'll upgrade to stand-alone management. I like being able to tune on every part of the spectrum - ignition, fuel, and boost - all in one easy step.

Ok, too many things in this thread to remember them all so I'll give it my best shot.

Uhh... You can't have a daily driver that's also a dedicated drifter. How 'bout a daily driver that you plan to drift on a regular basis. Dedicated means 'for a single purpose'. Just teasing! :)

These engine mods are going to put you in the Modified class in SCCA. If you don't go all out, as a competitor you'll be pretty far behind the guys that did.

The 'rev-limiting' problem sounds like a problem with the AFM but don't quote me on that.

$3000 is almost enough to cover the cost of the head work you'll need to hit the HP #'s you want.

The ZX is an OBD- nothing ECU. Think 1974 design slightly updated over 9 years to handle minor smog equipment changes and finally the turbo with an accelerated fuel curve to prevent lean condition under boost. Essentially only three sensors, TPS, AFM and O2 sensor.

The 280ZX turbo's came with NO intercooler, hence the 8psi boost maximum.

The P79 & P90 heads have 53.6 cc chambers which translate into lower compression ratios.

P90 w/ flat top pistons will give you only about 8.5:1 compression ratio.

The N42 & N47 have 44.6 cc chambers and will give you a 9.8:1 compression with flat-tops and 8.3:1 compression with dished pistons.

P79 or P90 head with dished pistons is going to give you about 7.4:1 compression. Not good for low-end torque.

P79 has a less than optimal combustion chamber for reliable turbo use and would be more prone to detonation.

Twin Turbos is pretty impractical on an inline 6.

7500 rpm is going to require significant investment in balancing and blue-printing, like holy-crap expensive!

Hi-end power and low-end torque are generally mutually exclusive design goals. It can be done, but it's an expensive proposition in it's own right.

Practical power in a 'streetable' L28 NA is about 250 engine hp or about 215 rear wheel horse power.

Here's a link to Rebello, arguably the authority on NA Z engines. Bear in mind, only one of these is a candidate for a daily driver. I'll let you guess which one.

http://www.rebelloracing.com/eng_info.htm

I think someone already mentioned the cam profiles are very different between NA and turbo cars. Don't mix and match.

Here's a linke to the only person I've ever heard of that cut absolutely NO corners: http://www.angelfire.com/extreme/280zxt/

Here's an idea of what it takes to make 320hp in a Normally Aspirated engine: http://www.betamotorsports.com/products/rod4sale.html

Clearly, this is not a daily driver.

I like the idea of using a T25 at 8psi in a 9:1 compression engine. Theoretically, with the right tuning it should give you good torque at the bottom end and good horsepower at the top end while maintaining your daily usability/reliability without the need to run racing gas as long as you stay off the boost... except when passing of course! :)