Unleaded valve seats in a Cooper S 163 Head

[rolesyboy]

Hi Folks. I am refurbishing my original AEG163 head and wondered if I can fit unleaded valve seats and if so where will I get hold of them? I understand these heads were prone to cracking and don't have a clue how risky doing the above would be. Also are there any worthwhile mods I can do while the head is in bits. Cheers. Mark

[scott6058]

I bought a 163 head from a fellow in Canada and he fitted seats and ran the head for me. Not knowing where he obtains the seats but it was done successfully. His name was Dyrk Bolger so shouldn't be hard to contact him. His business name was Classic Motor Works. 1-203-334-2415. I'm certain there are qualified techs closer but this guy helped. Hope this helps Scott

[Spider]

Giday rolesyboy, we have fitted stainless seats to these heads and if done right, it will reduce the tendency for them to crack between the seats. It does get super tricky / risky though if the Inlets need inserting too, but very possible. We made out seats from Stainless Steel Stock, I'd have to check to be sure which grade, but off hand, I think it was 314. Your machine shop of choice should be able to make or source appropriate Inserts.

[970s]

I had done one insert on my 163 head, and had to alert you it is risky since all head casting differs and consider it is an old head, if it runs OK on the original seats, let it be, it is not worth to mod the performance of your 163 head if you need a little bit HP! unless your head really need to repair/prevent the potential crack, and the valves you choose to use to cope with the seats may need modification as well, really not a ordinally mechanic job!

Al

[Vegard]

I must disagree. I'd fit seats in any 163 I'd use as this seriously reduses the likelyhood to crack.

[Nevsmini]

I had a cracked 163 head and I gave it to the head shop in Manchester and they fitted inlet and exhaust seat with great success. They fitted the inlets first and than cut into the edge of the inlet seat to fit the exhaust seats. But it was not cheap!

Nev

[Spider]

I had a cracked 163 head and I gave it to the head shop in Manchester and they fitted inlet and exhaust seat with great success. They fitted the inlets first and than cut into the edge of the inlet seat to fit the exhaust seats. But it was not cheap!

Nev

Interesting. We actually do them the other way around, as the first insert in has to be deeper (and so better heat transfer) and since there is less thermal stress on the Inlet Insert, it helps hold the Exhaust Insert in place, not on it's own of course!! But every little bit helps when there's so little there to start with.

The other thing we do is not to have too much interference fit (on these heads) as it only leads to the Inserts distorting, since the over-lap is partly unsupported, and then possibly falling out, that doesn't make for a good day

[rolesyboy]

Folks, thank you very much for your input. This forum really is excellentwhen it comes to supporting other enthusiasts. I will take on board the advice. Anywhere in the UK I could buy these valve seats off the shelf???? Cheers. Mark

[Nevsmini]

Will see if I can find some photos of the work. Spider that's interesting they used the same logic but reckoned the exhaust seat would need to be full size to deal with the heat. Strange!

[mk1]

Inserts should fit fine in a 163 as long as it is unmodified. I have used a number of heads modified in this way & have had no problems.

[Spider]

Will see if I can find some photos of the work. Spider that's interesting they used the same logic but reckoned the exhaust seat would need to be full size to deal with the heat. Strange!

Yeah, I am told it is unconventional and heads with smaller valve sizes we do fit full size Exhaust inserts. Another reason we do it that particular way with the 163 heads (or anything with the bigger valves) is that we are trying to get as much contact to the casting with the hottest (ie Exhaust) Insert. We are very limited on diameter, so we make up for that with depth and it assists with locking it in as I described above. I'll also say that while it is usually possible to Insert heads with the biggest valves, it certainly is not something that should be done lightly and the absolute utmost of care is needed, or could turn out expensive.

[251 ENG]

Hello Spider

What interfearance do you give your inserts in 163 heads ?

Also what diameter do you use and how deep do you cut them ?

[Nevsmini]

Found some photos of my 163 head with seats fitted.