Mopar Muscle Association UK

Hi, can I fit hardened valveseats to my '71 383 heads. I am a bit worried about not enough 'meat' on the sides of the valve.
thanks

You can fit hardened seats to any head as far as I know. I am not sure I understand what you mean about 'meat on the valves'? The existing seat area in the head is cut out and an insert pressed in. It is then machined to the same dimensions as the original.

383, 400 and 440 engines all share the same heads BTW. In 1971 the common casting was '346. The heads from other years are totally interchangeable. So if you can find a set of 1976-78 '452 heads you can fit those as they already have the hardened seats.

Thanks Dave,
the guy at the engin shop just said to me he knows some of the chevy heads, like 327 can't always take hardened valveseats, if they take away from the head, they end up going through the sides. He was not sure about the Chrysler heads, if there is enough material around the valvestem to fit hardened seals?

I would like to use the heads as is, its #matching.It's not a big deal, otherwise I'll keep on using a additive and leave the heads standard
thanks again

Didn't know that about Chevy heads. I have not heard of any Mopar heads with this problem.

If it was me I would use the heads as is without additives. If and when the time came when I felt it needed new seats I would do it then.

I tend to take the heads off anyway every 2-3 years to give them a clean-up and check the engine bits out so I would notice any changes.

However all this is easy for me to say because I have had hardened seats fitted in my '68-'70 '906 heads anyway when I had them ported.

Plus I never do much more than 2500 miles a year so even if I didn't have hardened seats it would take ages for any bad effects to show themselves.

You may feel you want peace of mind and you may not want to pull the heads every now and again. In that case you should do it so you can forget about it.

Thanks Dave, I think I'll leave them as is, the engine looks exellent on the inside and my mileage will not be more than a few hundred a year.
cheers