AJ,
The engines were designed to rev. And even though overdrive transmissions had already been around for decades, BMW’s engineers never made an overdrive transmission available from the factory on an ‘02. Why? because everything that happens on an ‘02’s M10 happens above 3,500 rpms.
Yes, if your daily driver is turning 2,000 rpms at 70 mph, an occasional drive in an ‘02 — 4,000 rpms at 70 with my ‘76’s original 3.90 differential — may seem a bit...busy! But deal with your exhaust leaks so you can actually drive the car now! The more you drive it, the less you notice the...busy-ness!
As stated above, make certain you have 20W-50 oil in the car. Feel free to overhaul the carb (Solex or Weber), if it’s not been overhauled in the last 4 years or 40,000 miles — hint, odds are that it’s not been.
Even when you do a “performance build” on a 2002, there are elements that could carryover. One thought is the following. There is a strong movement towards the electronic “123 distributor”. Find some of the long, endlessly-raving threads discussing it on this forum. If you think it might appeal to you, buy it now. You can tune it to your car’s current state, and it will eliminate a common “high-mileage M10” ailment: the distributors are worn, have lots of slop, and have lost their original advance/retard curves. When your engine has new pistons, higher compression, a hotter cam, etc., you’ll just use the 123’s app to adjust the curve for the “new M10”.
Welcome to ‘02’s, and don’t be afraid to rev an M10. I contend that anything less than 2,500 rpms is lugging the engine and no one wants to do that.... ?
Regards,
Steve