Thought I'd post a bit of an update on ownership so far.
Perhaps being a bit over-cautious running at stage 4.25, I decided that I didn't want to risk throwing a rod through my block. I know many people do run this power level and even more without any issues but many don't and if it goes, it's new engine time. Given the mileage on my car (60k), I decided to get reduce the risk and got myself booked into Litchfield for a few upgrades
The main work to be done was to get the engine out and stripped, rebuild with forged rods, new bearings, gaskets and a bunch of other nice things. Controversially perhaps, I opted to not get the pistons changed for forged ones as this involved a lot more machine work (and cost), though I did have new piston rings on the OEM pistons. Not being interested in running 'big' power on this car and wanting the reliability overall, I didn't think it would have been worth it as I'd never see the benefit. Not to mention the other costs in involved in upgrading the gearbox etc to take advantage of the engine's capability had I gone down that route.
At the same time, I upgraded the turbos for some with GT30 cores and billet compressors to get to a comfortable power level and had all other drivetrain fluids changed.
Once the engine had been taken out and stripped, it was found that the timing chain had stretched and the tensioner was at max. extension. Luckily this was caught in time so had all chains replaced with the tensioner. Everything else internally seemed to be in very good condition, so I was quite pleased overall.
A few pics:
Shortblock stripped and cleaned
Engine fully rebuilt and assembled. Added black powder coated covers all round
Nice little touch
Refitted and all cleaned up
Dyno Print Out
Bonus Car Shot
Overall, the car drives very similar to how it did before - comes on power around the same sort of time with the same sort of torque level. It just holds it consistently right up to the red line rather than dropping off like it did before. The new turbos are barely breaking a sweat at 1.2-1.3bar boost - they needed to be dialled back in a bit as the first few runs were touching high 800's
Eventually, I plan to do a bit of basic work to the gearbox to allow the torque to get pushed up a bit more across the whole range and maybe get a bit more power wise to go with but not a lot. For now, I think I'll enjoy it a bit without worrying!