Hardened Exhaust Seats

Dave1931Pickup

Senior Member
My '31 Pickup has a fully built touring engine with hardened exhaust seats. I'm now rebuilding my wife's '30 Coupe which will not be a touring car but rather just used for short trips. Are hardened exhaust seats necessary?
Thanks, Dave
 
It sounds like the Coupe won't be doing many miles and what it does will be at low speeds. I wouldn't bother.
Henry didn't use them and there were thousands of Model As criss-crossing the country. The engine I use for long trips (up to 12,000 miles) does not have hardened seats
 
If you do not use the hardened seats, keep an eye on the valve clearances as they can change as the seat wears. A friend found one exhaust valve with only 0.002 clearance, but this is an extreme case.
 
It depends on how much the seats were previously ground , the seating area can be too wide and the valve can be sitting too low , some engines should have all the seats replaced
 
It depends on how much the seats were previously ground , the seating area can be too wide and the valve can be sitting too low , some engines should have all the seats replaced

I should have mentioned that. Hardened seats are a good way of overcoming worn seats in a high mileage engine. I use a lead replacement additive in the fuel to prevent valve seat recession.
 
Back
Top