Re: 258 performance mods or upgrades
I was recently forced to rebuild my 258, and I performed the following with excellent results. My engine was a dog, but now it pulls HARD.
1. Bored block .060 over taking displacement up to around a 4.3L, installed new pistons
2. Machined the head, 3-way valve job all to bring up compression
3. Cleaned the entire engine in the tank, ridding it of about 150,000 miles of built up chud, installed new oil pump and full gasket kit
4. Installed Crane Torque Cam (1500-4500RPM power curve), plenty of bang for the buck at around $120 bucks
5. Added Holley 350 2-barrel Carb to the factory intake which I polished myself. I felt that the Holley was a better deal than the Weber, and was WAY easier to find parts for.
6. Finally bolted on a Pacesetter header so she could breath a little better (not too many choices on a header for me being that i have a YJ).
The finished product is night and day from where I started. Before I had problems stalling on an incline or deep sand, now I just blast through it. Pulling out into traffic the other day I had to stomp on it, and actually started roasting my swampers. Oops, but it made me appreciate how well it had come together. Good luck on the engine!