I know someone whose next project is to replace the ailing engine in his Jaguar XJS with a small block 350. This conversion has been done with success by many others. This person has an Austin A40, Austin Healy Sprite and an MGBGT so he has an appreciation for classic cars in stock form. I know someone else who has been toying with the idea of putting a Jaguar motor that is in good shape into a TR3. He is also a British sports car afficianado who owns a Jag 12OS, an early Healy 3000 and an unrestored daily driver TR3 so he is not your average hot rodder type but someone who has an appreciation for classic cars but is just thinking of doing something different.The purists will say don't do it to the TR3/Jag project but others will say it's his car he can do what he wants with it. But I was wondering about the actual practicality of putting a Six cylinder Jag motor in the TR3. Would the battery box and firewall have to be cut out for the power train to fit? what about motor mount location?Would there be much difference in the weight of the engines? Would there be a notable increase in torque and power to make it a worthwhile project. Or is this project just too :indecisiveness:far out in left field? Any thoughts?