Early head info 289/302/351W

[1964comet]

My chevy friend have been telling me about how early chevy heads have to have hardened seats installed(for unleaded gas), and telling me the same is true for Fords.

Does anyone have any info on this, I have a 64-1/2 289 (5 bolt) that I was going to install some '71 351w heads with a small SC and fuel injection for a 64 comet hardtop, should I be concerned?

I believe for the price of getting the heads converted, I could buy GT40 heads or the like,
Any info would be appreciated,
Andy

 

[5.0StangRacer]

I'm almost positive that 289 heads do not have hardened seats

 

[rbohm]

while pre 1974 heads of all makes were not designed for unleaded fuel, these days there is no concern about running these heads on unleaded fuel. one of the things lead did was lubricate the valve seats preventing valve recession, and installing hardened valve seats was the rage in the mid 70's to early 80's. the reasons they are no longer needed are;

1: valve recession isnt as bad as people thought it would be for most engines. you really had to whip your engine for valve recession to be a problem.

2: the second reason is that the oil companies started adding a lubricant to their fuel blend to prevent valve recession.

 

[kwkenf]

When I had my heads rebuilt, I used hardened seats.

 

[Max Power]

I hope point number 2 is correct. I can attest to point one not being entirely correct.

My valves on the exhaust side were the thickness of a quarter deep into the seats when I pulled my heads last fall.

 

[1964comet]

Thanks

Thanks for the heads up,
I think I will run the windsor heads since I have them
and see how it goes,
Andy

 

[67CoupeDriva]

I'm with Max Power...I had some significant valve seat recession in my bone stock C code 289. Replaced with 5.0 heads at the time (cheap & quick). IMO, it's cheap insurance if you're running the older heads.