hi there every one just wondering what sort of performance mods you can do to the boss 260 engine, with out spending a mint, i already have the following on my ute

growler cold air intake, hm extractors, twin 2 1/2 '' red back exhaust, 25% underdrive pulley kit, capa flash tune (but just the standard tunes)

Sound like you've got most of the smaller mods you can do. Maybe larger throttle body, cams, injectors, port n polish heads (done your self if you know what your doing). But if you can put around 5-6 grand together you should supercharge it. Everything else you do to it will never be enough.

That's right, from here on out, it gets expensive.



larger TB, is useless until you're making A LOT of power.

cams - not worthwhile on a BOSS260, unless you also raise the compression ratio (meaning bottom end rebuild)

injectors - not worthwhile until making more than ~350RWKW

For now, next steps I'd recommend...
- upgrade exhaust (those components you've already got aren't the best out there - look for DiFillipo headers and exhaust)
- custom tune (these are expensive, so get all the hardware you want done first, and get it tuned once).

Can you get the compression up enough with a surface grind?

lol no.

260 is 9.5:1 (means they love boost!)

290 spec is 10.5:1
302/315 spec is 10.8:1