[junglejustice]

Dunno man! There's about 10 ways that you can go here, but at the end of the day, it comes down to budget (and time...)

1) Eliminating turbo-charging as an option for now (already mentioned - and besides - you would still have the limitations of the standard internals that would need to be upgraded at some point any way!)

2) Eliminating supercharging as an option as per your request (and also see the points in number 1 above!)

3) Bolt-on stuff; I had very good success with the large-large 50mm cast aluminium intake-runners and modified plenum from South Africa on my (otherwise standard) 3.0 litre 12 valve street/track Milano/75! Coupled with programmable fuel and timing (I used the GoTech for price and convenience sake), this also eliminated the restrictive flapper-crapper air-flow meter!

I had a good set of headers (also from SA) and ended up somewhere around 173 to 180 at the wheels on two different dynos back-to-back on the same day - A DynoJet and a Mustang dyno (the Mustang read higher BTW...) It took a bit of work on my side to get it all dialed in right, but the guys around here knew that car and knows that it ran STRONG at the track for years!

I never even did cams, but you could then also add a set of Glenwood's Group 1 street/track cams and end up with a pretty nice "bolt-in" package (and power comfortably in the range that I mentioned above - on most any bloody dyno!) At this point you're likely somewhere around 200-210 naturally-aspirated crank-horses - not bad for not even unzipping her! Total cost for all four options will set you back 3,000 USD plus shipping though and now you're in the forced-induction territory in terms of parts-cost, which brings me to option number 4...!

4) For 3 grand you are also half-way towards a nice rebuild on a 3.0 12 valve with larger valves, the pistons and rods modified for higher compression, a good port-job and decent balancing! Now, you still need the other 3K for the performance parts-list mentioned in point number 3 above however, you should now be somewhere around 7K (by the time you add a gasket-set and assembly labor), maybe 8K or so!

You're now sitting on a brand new 10.4:1 compression motor with about 220-230 horses, programmable fuel and timing, multi-coils, custom cams, custom intakes, custom headers, pump-gas and lots of bang for the buck! Still, this now also bumps you right into option number 5 on the list -

5) Taking a converted 24 valve package for around 9K USD (good, low-mile standard 3.0 with 10.0:1 compression) and adding the GTA Stage I or Stage II cams, again the GoTech (but this time the Pro or Pro-X model), correct oval-port headers, 44mm GTA/Q intake runners, modified plenum (and again - no flapper-crapper AFM...)

Now you're closer to an honest 260-270 horses (seeing perhaps 215-220 at the wheels at sea-level), again on pump-gas! This is as far as you can take things in my opinion before sending you into 5-digit rebuild cost territory!

6) From here you jump to a few thousand more for a built 3.2 litre GTA donk, then a 3.45 - above that a bit - then a 3.7, then a full-race whatever of whichever option - on and on... It never stops! With the big-bores you also end up with forged steel chrome molly connecting rods, forged aluminium-alloy pistons, a wider-range of cam options and total flexibility in final compression-ratios!

Now you also have to start comparing and re-thing things yet again, because you could be building a strong 9.5:1 24 valve 3.0 for example and go with twin-turbos and blow the damn NA 3.7 out of the water!