VI engine with IV turbo or VIII turbo

[SaulHudson]

Like the title, I have a VI engine, and I have a IV turbo. Should I use the IV turbo or get a VIII turbo? I don't want to pay the price for for VI or a IX with the bigger hotsides. Should I go halfway in between the two hot sides ie9.8 on the VIII vs the on the IV and the 10.5 on the VI? How much will this hotside mess with my ecu? Will the IV be pretty bad on my ecu? Using the IV ecu.

 

[RsvRob]

Fitting the 4 turbo is fine. Fitting a newer turbo thats bigger will alter your performance and remap would be prefered

 

[SaulHudson]

Cool Thanks.