Hi guys I'm putting a Barra in to a GQ patrol and was just thinking what size turbo should i get?? with the gearbox and diff gears i'm running it will be sitting on 2800rpm at 100kph so I was thinking I would like to get it to start spooling at about 2500 to 2800rpm that was when i pull her back to 4th its right to go.. also this is my tow car for my race car... the GQ is 2800kg so with the added load when do you think a GT42 with a 1.06 rear housing start to spool...?

Gt 42? Even with a spool valve it will still spool around 4000 or there abouts. Just get a gt3582r, gtx3582r or an fg turbo if you dont plan on running crazy boost.

58 to 62mm turbo with 1.06 t3 or .81 AR on t04 turbine ..
High compression low boost for heavy-sh vehicle ..
Gives way good throttle response ..