Rawze.com: Rawze's ISX Technical Discussion and more

I haven't been able to find a definitive answer if the ISB 2250/2350 fuel decay/leak test specs are about the same with the 4000 psi drop over a minute. Most of what I find is more about measuring flow return rates similar to Duramax engines. Can you use the decay test on the ISBs like the ISX's?

Ive done the test on my isc, not sure how similar isb and isc are.

Yes it would be the same, doesn't matter which cummins common rail engine you have.