441 cyl heads
 

Several years ago I purchased a set of 441 cyl heads from a super stock racer who guaranteed me that were not cracked and I thought I asked if they were super stock legal. I just recently started to disassemble them and noticed that the intake valves measure at 2.02 and not 1.94. My question is, can I have all the seats replaced in order to go back to the legal valve size of 1.94? Thanks in advance for any and all input.

Re: 441 cyl heads
 

You can probably grind the seats back to 1.94 by using a 30 degree stone to grind the 45 to be smaller . It would depend partially how they were opened up and its not optimal because you are probaply going to sink the valves a bit doing this. Also i have a set of 441's if you need them.

Re: 441 cyl heads
 

Rick..call someone like Dave Layer who. has done many sets of 441 castings for super stock..or better yet call NHRA and pitition them to make the 2.02 valve legal..what the heck it's a long shot lol..Luke SS 311

Re: 441 cyl heads
 

Yes....Its legal to replace the seats. NHRA OK'ed this a few years ago and IHRA has allowed it almost forever to save rare hard to get casting from becoming junk.
If possable find a shop that uses an adjustable cutter for the seat and guide machine such as a K.O. Lee machine so you can use a little more interfearence (approx .004) fit for the seat ring than the non adjustable standard cutters so they won't come lose and fall out from the hi RPM use. . Make sure the shop uses a sealer/locking liquid compound and freeze the seat rigs before installing them in a warm/hot head. With this method I never had a failure in over 40 years of replacing seats. Use a little more interfearence fit when installing them in alum. heads.

Re: 441 cyl heads
 

Very well said Terry!;)

Re: 441 cyl heads
 

Thanks.....This suggestion helped Lee Edwards (Pro Stock racer from Va.) during a conversation we had at Rockingham back in the early 70s. He was dropping seat rings right and left damaging a lot of parts. After he used more interfearence fit on the alum. Chev. heads and the sealing compound made by "Locktite" it stopped the carnage. I might be old but Im not stupid....LOL. well except maybe wanting to go racing again as part of my "bucket list" might make me dumb !.

Re: 441 cyl heads
 

Rick, if you need a virgin set I have them.

Re: 441 cyl heads
 

Just to let everyone know: It might not be a good idea to freeze the seat rings any more.
I was putting in an oversized ring the way I've done it for years. Heat head and cool the ring.
using an extra .002 fit because the type head was known for dropping rings. The first ring shattered when I hit the driver. Then I pulled the second ring out of the box and checked the size and my fit.. Looked good. Re heated the head and and froze the ring... Same results. Ring shattered. I picked up the phone and called Tech at the seat mfg. The first thing the guy ask me was if I was freezing the ring. Yes--- Don't freeze them was his suggestion. Seems that the metal in the type ring I was using was hardemed & doesn't like to be cold and take a strike from the driver. He said it is OK to freeze some, but the type seat I was installing didn't like the freezing process. It was the correct ring this company suggested for the application.
Sad thing is I killed 2 high dollar seat rings before I learned a lesson. I then read their instructions and there is not one word about freezing in them. They did have some suggested heating temps for alum and cast heads. Remember: not all Loctite solutions are correct for seat applications. Use the correct one. I've been told that some of their compounds don't let the heat transfer out of the hot ex seats to the head. They act as an insulator. In other words it is not the correct place for their thread locker!
The seat thing just goes to show me that not all the processes I've used for years apply to todays new and improved parts.

Re: 441 cyl heads
 

Loctite used to make a seat ring locker just for this job. It wasnt a thread locker. Its been awhile since I have done this type of work but I never had a problem of shattered seat rings. May the new stuff isnt so good after all....LOL.

Re: 441 cyl heads
 

The current "hot tip" on fluid used to install seats is called seal-lock. It comes in a small bottle similar to the paint marker bottles you see at the salvage yard. The fluid itself is somewhat thin, and a blue-white color. I think Goodson and Silver Seal sell it. It's fairly expensive, not priced anything like Loctite.

A lot of the new seats are made of a tough powdered metal material. As with any ferrous alloy, the harder you make it, the more brittle it becomes. Some of the elements used to make ferrous alloys hard are temperature sensitive, and cold makes them even more brittle. They won't hold up to being struck unsupported at 0 degrees (your freezer is that cold) or colder. They're fine when they're held in place and supported by the seat pocket you cut in the head, because they cannot flex.