I guy on here Paul Dauss ? goes by PD has run them.he is on the open RWYB side most
of the time.I also missed spoke on the heads,the intek and animal are the same but
the vanguard head is the same but not the port.the intek is a bushing block but
bearing side cover of animal or vanguard will fit.also the vanguard is dual bearing
like the animal
The Intek head has the same port angles as an Animal head but has a huge restriction in the intake port.
One would have to precisely machine (not die grind) that restriction out to match the flow of an animal head.
For an Open engine (the only place you could legally use such a head) increasing the flow will have more advantage than a higher velocity.