I'd try and keep it below 4k, but no lugging, until it's warmed up.I run custom N from start - I just change gear at 5k and don't use full throttle until the temp dial has got close to "normal" (never liked normal steering weight or throttle feel)
Yeah I probably should have been clearer - gradual rev rise as temps rise rather than up to 5k from cold cold...I'd try and keep it below 4k, but no lugging, until it's warmed up.