Car not running right after upgrading to 1300cc Injectors and twin fuel pump

Mariokart

Hey guys!

Hoping someone else has had a similar problem so I can get it worked out asap.

My car went into the shop running perfect,L with no issues. I had ID 1050 Injectors and single Walbro 450 pump.

I was maxed out on fuel so as per instruction from seb at specialty z I got my car into the shop to upgrade Injectors to 1300cc and to a Cjm twin pump set up. Second pump is a Walbro 520 and is controlled with a hobb switch on it's own seperate relay.

As seb is my tuner I didn't have the shop do any tuning.. Just do the install. Upon leaving the shop my car was idling very high a 1400 rpm and also wouldn't accelerate past 2.5k rpm it would just bounce at those revs.

Seb has sent me a tune update but it hasn't changed any of the issue at this stage. Just wondering if anyone may have come across something similar and has some input to help here.

Many thanks! Merry Christmas z fam.