[Isaac Zachary]

1. 2. 3. and 12.

Aluminum parts that are under high stress will not last long. I'd forget about aluminum cranks, connecting rods and rockers unless you're ok with replacing that sort of stuff every year or so.

You could do titanium rods, but not worth it in my opinion. Those need to be very well designed and treated so as to prevent galling.

In the end, I don't think 1. 2. or 3. would be worth lightening unless you're trying to make a high revving racing engine. But for fuel mileage you won't notice a difference IMO.

You're best bet is a lighter flywheel, which is what you'd want to do before trying to lighten anything else of the rotating assembly. But whether a lighter flywheel will help or not depends on one thing: are you going to be accelerating and decelrating a lot? A heavy flywheel won't noticeably hurt fuel mileage if you're just going to get on the highway and cruise. But around town a heavier flywheel takes more energy to spin up and then releases more energy spinning back down.

4. 5. 6. 7.

These are great ideas!

8.

Have you seen the thread where someone took an A/C pump clutch and put it on his power steering pump? That way the power steering could be turned on and off as needed.

9.

Nice idea.

10.

How is this going to help fuel mileage? I'd say just change your oil regularly (every 3,000 miles or 3 months for your engine) and use a good filter and good oil.

14.

I saw an interesting idea for unequal length headers for a crossplane V8. There are also 2 into 2 headers that accomplish a similar idea. I wonder if you could make them long enough (depending on your RPM goal) to connect the two end cylinders of one bank with the two middle cylinders of the other bank to create 180° firing order manifolds...

The problem with a crossplane is you have firing interavals of 270° 180° 90° 180° on each side. That 90° space between the two cylinders means you have one cylinder starting it's exhaust cycle while another is still in it's exhaust cycle on the same exhaust manifold. That means more back pressure for those cylinders.

Or you could try to convert to a flatplane crank and have all 180° firings on one side, but then you'd have a secondary imbalance.

16.

This is a great idea. Dynamically ballancing with the pistons and rods is best. A crossplane crank cancels out primary imbalance of the pistons by means of counterweights.

18.

Hypereutectic pistons hands down! These are lightweight and expand less than any other aluminum piston letting you build with tighter piston to cylinder tolerances, so less blowby and less friction. They are also less conductive to heat so they keep more of your heat in the engine, kind of like with ceramic coatings.

I'd go with good cast iron rings too for best wear.

20.

Man! There is so much you can do tuning, I'm going to have to get back to you on that! Tuning is where it's at!