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.