rb20 swap to rb25 engine

[charmcitydrifter]

ok so i swapped a rb20 into my s14 and 2 weeks after i swapped it my engine leaned out and blew a piston. i found a local place to get a new engine but he is out of rb20s and mentioned getting a rb25 engine. i know the trans will bolt up, and the mounts should, what kind of wiring issues will i run into? any help would be appreciated.
p.s anyone whose gonna comment "do your research blah blah blah" i did but im in a bit of a time crunch if you dont wont want to help me gtfo and dont waste my time please.

thanks in advance

[fliprayzin240sx]

VVT timing is the biggest difference since the RB20 doesnt have it.

[240sxbaltimoremd]

what shop are you taking it to?

[charmcitydrifter]

im not taking it to a shop.

[PrimeDirective]

You're going to need a mount kit if you have the stock crossmember. There is no way the stock RB mounts will fit on the stock KA cross member with out hitting the firewall.

[Paparazzi]

You're going to need a mount kit if you have the stock crossmember. There is no way the stock RB mounts will fit on the stock KA cross member with out hitting the firewall.

He already has the rb in the car, so the mounts would have already been addressed. OP what mounts are you running? Are you running the rb20 cross member?

[bllabong89]

Buy a wiring specialties or another ore made harness and you won't have to deal with any wiring. I just installed mine and it runs so much smoother. If you have the mounts and everything was running with the rb20, it should just be wiring