[Dejavu]

I was given a 1975 302 that has very low original miles (I know it has never been rebored) and when I tore it down showed very little wear. The heads are set up for a smog pump so they have a huge hump at the top of of each exhaust port. I have port matched and done a little head work before but want to know; Can I grind these humps off? and will the labor (free) be worth the trouble on these smog heads?
Thanks,
Fred

[357f-150]

You can grind the thermactor bump down....


On a flow bench it shows minimal cfm gains by doing so, yeah, I was just as suprised, but every little bit counts. Do a search, there are a few indepth websites demonstrating what should and should not be done to the sbf head. They are mainly geared towards the E7 casting but the principals apply.


Have fun.

[Dejavu]

Thanks for your reply

[fitzwell]

you CAN grind out the thermactor port, but...grind too far (and it aint much) and you will strike water.

do not ask me how i know this

[Dejavu]

The more I search the clearer it gets these heads are boat anchor material. The motor is in such good shape internally, I will try to find a home for it. I am going with a 351W crate motor for my project so this was just a distraction anyway.
Thanks,
Fred