[slowmover]

I see a lot of ecomodding ideas, aero, etc, but not as much in discussion about the basic mechanical and "tune up" areas. I see a lot of older cars being modded here, but seldom does mechanical maintenance come up in discussions?

There may be the assumption that the owner has already "baselined" the vehicle. I consider that starting with a set of certified scale tickets:

1] Driver, full fuel & all items that are aboard permanently: Total weight adduced from two axle totals
2] Weigh each side of vehicle to get individual wheel positions.
3] This is total of three scale receipts: At a CAT Scale

Tire pressure dialled in from vehicle manufacturer data and RMA book (see CapriRacer's site: Barry's Tire Tech). Basically, a 15% load reserve above load versus pressure table (that fits within vehicle manufacturer range of pressures).

With that, proper alignment (painstaking). Wheel bearing service and proper preload (this is more open to interpretation than it should be). Same for no brake drag on calipers and fine adjustment of rear drums + emergency brake actuation.

Zero steering wander: KENWORTH (among others) cites excessive number of steering corrections per hundred miles as a source of poor FE. Rebuilding the steering apparatus should be high on list. At the same time, other front end componentry and body/frame bushings.

Rear spring sag. A lifetime of being torqued over in one direction can cause rear springs to have settled unevenly. Luckily, leafs are basically cheap.

Any adjustments in FSM to the auto trans? Are shift points at recommended rpm?

Obviously, all new fluids, filters, belts & hoses. The cooling system needs real attention for FE. Non-EFI motors have a hard time with temp regulation. So start with a pressure test. Etc. And use some RMI-25 to gently clean as you drive. I've used it more than 20-years.

Yes, sounds like valve stem leakage. A rebuilt head isn't all that expensive (as valve stems are a PITA given old tired springs also present). A compression test before & after. And a blowby test. If any cracked rings, then . . . .

Etc.

As I mentioned in another thread, do new seatbelts first, then brakes/tires. Safety, then FE, as they work in tandem with one another in this pursuit.

A new windshield for a vehicle with over 150k is also good. Clean with muriatic acid at 1:50 water (if you're brave) if no cracks. Frankly, they tend to be "sandblasted".

Next item is all new fuses & relays. New lamps, interior & exterior. Run headlamps off of a relay-driven BATT power (13V at lamp; see Daniel Stern site) to make things bright. Check voltage at rear lamps (and consider some kind of decent LED upgrade, not just pop-in lamps in housings not designed for same).

And ETC, again. The list is never ending, but the basics should be covered as above, IMO.

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