beryllium seats, guide clearance?

[KendallF]

I am working on my heads, and cussing. Lots. I have S2 heads that came from 2 different motors, with the variety of problems that entails. One has beryllium exhaust seats, and I'm considering whether to change them or not..car will be probably 75% track car and will see limited (if any) pump gas. Opinions?

Secondly, I have about .0017-.002" clearance in the exhaust guides; the machinist who's working on them with me would like .0015" but I'm wondering what others are using in S2 heads. With the extreme heat load I'm thinking .002" might be OK but I don't want it puking oil in the chamber either.

Thirdly (sigh) I have seat heights that appear to be all over the place; I'm making a jig to allow measuring seat height from the deck surface and we're going to determine the low one and machine the rest. I have a mishmash of valves; the intakes are new Ferreas that are actually called out as a Brodix #12 application (2.05, SBC+.400 long). I will probably buy some new exhausts as well and any input on what's being used w/T&D rockers would be appreciated, as well as maximum stem height mismatch that the T&Ds will tolerate.

On a good note I did cc a chamber on each head and before they started leaking (did I mention the dings in the deck that I need to surface? ) I got 50+ ccs on both heads...

Help! I've low-bucked myself to death again!

[Mac in SD]

Re: the exhaust seats. That depends, Kendall. Are those seats Siberian beryllium or Madagascar beryllium? It makes a huge difference, as I'm sure you know.

As I've said in a previous, unrelated post:
Kendall...you're completely out of control. You do realize that, don't you?

[DonWG]

Beryllium seats will transfer heat from the valve 4-7 times (difference is in which alloy you have) better than iron seats. If you expect a problem with getting your exhaust valves too hot, you might want to keep the beryllium. They will wear quicker though. They're softer than iron seats. They're usually recommended when your using titanium valves. Guide clearance does not sound like too much. Hey MAC.

[opeltwinturbo]

Kendall: I prefer the Madagascar Beryllium ! The last two episodes with head problems that I had were turned over to EICKE RACING ENGINES. Dale Eicke, a well respected former Prostock team owner and engine builder, just finished repairing the heads that were damaged on the Opel at Bowling Green this year. He knows the heads. Give him a call at 740-349-0213. Be patient, he is sometimes hard to reach. 50+cc is good. Mine were just over 45. Don't you think you are asking for trouble trying to run this motor on the street as well as at the track. Sounds like a goofy idea that I would try. Good luck.

John Schmidt
BPG #1003

[The Radius Kid]

I'm with the guys on the Madagascar thing.Just make sure the ore was refined by the Maui- Maui tribe.
In all seriousness,your guide clearance sounds perfect.
I would;
Chamfer the tops of the exhaust valve guides.
Lightly polish the exhaust valve stems with 1 grit paper and motor oil[obviously wash them after wards].
Leave off the exhaust stem seals[your clearances and the chamfering should keep it from smoking].
That's how I would handle it.
Of course,I'm assuming standard stainless exhaust valves here.

[EightSecV6]

DEAR GOD!!! you guys could drive even someone as anal as me nuts!!!!My sympathy to your engine builders!!!!!!!!!!!!!!!

[The Radius Kid]

Hee hee,it's a wonderful world,ain't it?

[KendallF]

Well, thanks for the input, everyone.. You too, Bill. I am just trying to get the heads sorted out and if you're going to give sympathy to anyone, it'd be me as I'm building the thing.

I hate asking tech questions because when I do, they're usually arcane enough where I either get no response or humor. Nothing wrong w/humor but I still want to know what I can get away with on the heads!

[Mac in SD]

Sorry about the humor, Kendall. I guess I was using humor to compensate for my inadequate knowledge of valve seat materials, and my consequent inability to provide you any meaningful assistance in this case. Mea culpa.

However, the fact remains that, as I've said in previous posts:
Kendall...you're completely out of control. You do realize that, don't you?

[EightSecV6]

The seats in the heads will be fine,you can probably get away with .0015 on the Int. valve but I would go .002 on the exh. As far as length goes, you'd have to determine what will work after you grind the valve seats. You can shim the T&D's up a little or machine the head down to get the geometry correct. T&D makes a little "T" shaped tool to determine if you have it right or not.
If you put new exh guides in make sure they are machined down to only .250 or so sticking into the port or your turbo will never forgive you.

[KendallF]

Originally posted by Mac in SD
Sorry about the humor, Kendall. I guess I was using humor to compensate for my inadequate knowledge of valve seat materials, and my consequent inability to provide you any meaningful assistance in this case. Mea culpa.

However, the fact remains that, as I've said in previous posts:
Kendall...you're completely out of control. You do realize that, don't you?

That was humor?! No wonder I couldn't find any reference to Madagascar beryllium mines on the web. I do appreciate everybody's input; I'm not a humorless SOB, really I'm not! Oh, and I'm not out of control, I'm just transportationally challenged.

Originally posted by EightSecV6
The seats in the heads will be fine,you can probably get away with .0015 on the Int. valve but I would go .002 on the exh. As far as length goes, you'd have to determine what will work after you grind the valve seats. You can shim the T&D's up a little or machine the head down to get the geometry correct. T&D makes a little "T" shaped tool to determine if you have it right or not.
If you put new exh guides in make sure they are machined down to only .250 or so sticking into the port or your turbo will never forgive you.

Thanks for the input, Bill! For the length, that's what I'm planning. I'm ordering one Ferrea exhaust valve; we'll make the cut to equalize seat heights and check lengths then, and if necessary order +/- whatever. I have to change one intake guide that's broken but the rest I will probably leave. I am currently planning on cutting the exhaust seats .020" lower than the intakes as that's what Ruggles recommended in an old book I have. I currently have basically no guide extending into the port on the exhausts so they should be good.