Comparing 500Hp to a 302 Ford engine to a 557 big block,
we see the 302 needs to rev to 6500RPM whereas the 557 hits it at 4000RPM.
Further the 302 would be describe as a racing engine, an you might just call the 557 a truck mill.
786Tq or 1.34Tq/CID
Peak Hp 860 @ 6200rpm
More CID takes a lot of cam to make RPM, but the torque peak will be much the same even if it occurs at a lower RPM
1.33Tq/CID.
As CID goes up efficiency is impacted by friction so the Tq/CID number will be less.
A 632 can make 900Tq or 1.42Tq/CID
1.42Tq/CID.
Long duration cam and lots of compression
This is a 454 making 1.31Tq/CID
It will be a milder big block to manage.
Add more CID and you can add a bigger head to make more power
1.43Tq/CID
While this motor has less CID, the Tq is up due to more compression and more cam duration which exchanges low RPM torque for higher RPM torque.
1.43Tq/CID
I want to illustrate that torque comes from CID
This over bore 350 is making 507Tq which means it produces 1.4Tq/CID which is very high and requires very fine tuning.
Any AFR head will make 1.3Tq/CID without much effort.
If you cam a motor more or less, you move the torque curve, but a glace at the Hp curve at a given RPM will give you a sense of what to expect.
This 434 is a great platform for a maximum torque small block.
1.32Tq/CID
If it were a 383, it would make the same Hp, but at a higher RPM,
but torque would be 507lbs/ft and therefore less likely to snap an axle.
On this page I will add dyno test results.
It will remain a work in progress.
I'm just one of many V8 engine builders in the US.
I would gladly buy a motor from many of them if I didn't build motors.
To start I'll show you some graphs from Airflow Research.