You're right John, all TTA's engines in the 86's were bigport with the 40mm crank and they made supposedly around 230hp (realistically more like 195-200) and revved to 8700 for 6 hours straight. If you're punching pistons through the block on an N/A 4A you're having an issue rather than basic block strength. Only issues with bigports is the oil pump which is easily swapped and in standard form the cranks have a vibration issue at around 8300-8500 which causes them to flex and fail, again easily fixed with the proper preparation.

Also was expecting everyone to say I'm an idiot and use a smallport cause everyone else does so it must be better, so thanks for making my day with positivity guys haha.