PMSL Danny, you make me laugh mate
one point its "right i'm selling it" and now its "I want more power"!!
classic.
If you are going down the GT2871 route, WITH all the internals, then budget for around 9k, seriously, thats not an exaggeration if you want the job done properly and dont want the engine going bang.
That would be running a strong 380bhp, and maybe a little more, although I have read pushing the standard 5 speed gearbox towards 400bhp tends to strip gears....ask Hooch
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. Although his was 400bhp+ it is still pushing the standard box
with just an IHI or gt28rs with an .64 housing for example, this would give good spool, the same if not better than the gt2x BUT with the punch and power near to the redline. This would run anything from 315/320 (pegged) to 350 with the 28rs....but even with these power levels and on your high mileage engine I would be looking at rods at the very least
again, budget for at least 6-7k if going down this route
and completely agreeing with Phil, if you are going down this route then Bill is the man to go to
Why the sudden change mate?