Is the use of plastic alright for internal engine components or is that one of the reasons why the valvetrain is weak in 307's? Doesn't sound too great of an idea but maybe there is a reason for it? If I ever get the engine rebuilt, perhaps they could be upgraded to a heavy-duty material? I also get valve guides and seals confused, I always thought the guide was what "guided" the valve when it opens and closes, and if it goes bad there is play which lets oil to be combusted which causes blue smoke? Right? No? I'm not sure what the seals do at all.
I think I read somewhere that bronze (?) guides are best, and that steel ones have drawbacks of some sort? I'll have to dig up that article to confirm. If I pay for a rebuilt I want to make sure it doesn't self destruct again because of cheap pieces.
There was also an article in a 80's-early 90's Car Craft/Hot Rod/Popular Hot Rodding that had a Mondello build up of a "performance" 307 that used a 350 crank etc. It was an earlier 307 though (5A head). They did something with the main caps too. Maybe that would make the engine better in some way as far as durability?
I think I read somewhere that bronze (?) guides are best, and that steel ones have drawbacks of some sort? I'll have to dig up that article to confirm. If I pay for a rebuilt I want to make sure it doesn't self destruct again because of cheap pieces.
There was also an article in a 80's-early 90's Car Craft/Hot Rod/Popular Hot Rodding that had a Mondello build up of a "performance" 307 that used a 350 crank etc. It was an earlier 307 though (5A head). They did something with the main caps too. Maybe that would make the engine better in some way as far as durability?
