[quote=mahout;926237]

Quite correct and thats the problem when complying with SAE J1711 et al. And then there's budgets.
When we made cam, timing, jet or injection ports, valve, and manifold changes almost always we found that when the power changed significantly the emission curves exceeded the emission limits in Nox or CO or both.
Look at it this way, manufacturers aren't dumb. They really want the most that can be gotten with emissions and mpg market needs for 50,000 miles. If you don't have to meet all 3 there is some leeway. But that's coming to an end. I suspect it will be only a couple of years before such long range tests documentation, even in Cook county, that 'souped up' engines like we did evenin the eighties even are long gone.]
Those in the last 5 years just aren't worth the trouble cause they really didn'tpass the standards. But there's a lot of stuff out there that offers 30% gains when dynos only prove 3-4% and still meet emissions.

 

I do not need to worry about emissions havnt had to since it was done away with 15 years ago here in Florida... Besides nothing that a $20 tip to the inspector can't solve, I should know I've done it. The s2000 does 1hp per liter, na to boot. It's really not that hard with today's technology, look at a pair of heads from the 50's 60's era and compare them too today's, not just the material being lighter aluminum heads (although rare some did have aluminum heads back then) and the ports are night and day. Not to mention , variable valve timing, coil over plug

 

Great examples, IMO.

Port tuning and the ability to alter valve events allow Honda cylinder head to extract so much power from these little NA 4cyls and remain very efficient.

Now for a more unorthodox modern method for remarkable efficiency even on pump gas and almost impossible power curves out of small displacement motors:



Any one care to guess what's going on here?


I have a project underway basically identical to this one done by (fellow DSM'r) Paul Volk moving 80lbs/min airflow, or enough for well over 750awhp! There are several other examples now using all sorts of different configuration, including a guy named Kevin Jewer running high 8's, trapping high-150s!

We have the same radiator! haha

Fortunately I do not have emissions concerns for my 1G either (OBD1), and I'm honestly not especially eco-oriented, but when you mix $7/gallon toluene in with your 93 octane, and then spray 675cc/min of Methanol... you can learn to appreciate fuel economy! And if I dump less wasted charge and thermal energy out the exhaust as a side-effect to a good tune, that is a nice bonus. I do like to dump my wastegates to atmosphere (if I don't need to recirculate at least one) so less raw charge leaving the engine before the injectors cut on lifting off the throttle.

For further accuracy, I plan on having a second UEGO sensor and EGT probe between the primary and secondary turbos. As opposed to in Paul's set up, and just having the one UEGO sensor and no EGT on the downpipe after the second wastegate is recirculated back in.



Here's a crude diagram of what you are looking at:


He is making himself a new setup, and sold the one pictured for something like ~$3300.

 

Turbos are by far the most efficient power adder, it feeds off wasted energy for gods sake, but for some it's a love hate thing. In a sense it's like having two engines, you need to be on top off both turbo/motor to make sure it's up to par... ie checking for leaks every so often, temperature reading on the intake/turbo temp. Heck I may need to bite my tongue and become a turbo man if some tuner doesn't get the ball rolling on some n/a stuff. I'll admit some of the turbo cars I've been in make lasting impressions