450cc injector issue

[choard]

I have a 91' tsi and I installed a 4g63 turbo engine the same year, but out of an automatic car. It came stock with a t-25 and 390cc injectors. I installed a ported mani and 14b turbo. It runs with the 390s but i wanted 450s. I bought a set of them with the fuel rail and installed them on my engine and fired it up to find that it runs like crap. I sounds like im going to throw a rod(loud knocking in lower end) it also revs up real slow. So i put the 390s back on and it runs fine. What is the problem? Thanks guys

 

[El_Wood]

Your going to need something to tune with since your adding bigger injectors. Even though the 450cc are stock injectors your ecu is setup to run 390cc. Get a safc or a manual turbo ecu

 

[JusMX141]

That's because your ECU thinks the 390's are still in place. It's feeding the injectors the same duty cycle, but the injectors are dumping a higher volume of fuel into the engine.

Find a tuning device or a manual ECU.

 

[urban_Sq]

just go get a junk yard ecu quick fix plug and play

 

[trevnasty]

i second that junk yard ecu for sure

 

[choard]

it has a manual ecu in it

 

[JusMX141]

Then one (or more) of the injectors is bad.