vortec valve job

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RedRacer

vortec valve job

Post by RedRacer »

We have a stock car class that allows the vortec SBC heads, and requires a 1.94 intake valve max diameter. In an effort to keep the intake valve as high in the chamber as possible, would it be acceptable to install a seat ring for the intake? If so, can someone recommend a particular brand and seat material for a 2BBL motor on gas using a stainless valve? It seems like once we get a valve job on the head, the intake seat is down quite a bit, and also the options for different angles on the valve job are limited by the small amount of material in the casting when staying with the 1.94 diameter.
thanks, RR
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speedtalk
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Post by speedtalk »

Is there are porting rule? What can you do in the chamber?
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RedRacer

Post by RedRacer »

Ahh yes, that is kind of important info, isn't it! No porting, no chamber work... RR
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Post by speedtalk »

Since you can't legally blend the seat into the casting, I'm guessing it'll be a negative. If you're worried about the width of the top angle I'm sure you could get away with cutting it down with a chamber cutter
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These 2bbl motors really respond to the right camshaft - what are you doing there?
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RedRacer

Post by RedRacer »

Yeah the chamber sweep is for sure a decent way to go, but we are also trying to keep the chamber volume as small as possible. Also trying to get the exhaust valve lower than the intake valve like what Vizard had in his old cylinder head book. So if we put a small OD seat in the head, we can kill two birds in one shot.

Camshafts - well not too happy there either. Current cam guy is not too much in favor of running the lobe separation wider, and always wants more exhaust lobe, even though the motor is choke down and the theory says more intake lobe. Can you help us out there too? thanks, RR
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Post by speedtalk »

RedRacer wrote:Camshafts - well not too happy there either. Current cam guy is not too much in favor of running the lobe separation wider, and always wants more exhaust lobe, even though the motor is choke down and the theory says more intake lobe. Can you help us out there too? thanks, RR
Tell me more about this class. What's the cam rule? rocker ratio? which 2bbl do you have to run? is there a restrictor plate?
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RedRacer

Post by RedRacer »

Rules: stock bore/stroke (350SBC), flat tappet, stock rockers 1.5 ratio(stamped), 4412 holley, cast iron 2bbl intake, headers. I sent you an email Chris,

Thanks, RR
Denzil

Post by Denzil »

How about the acid ported cheater heads? I've never used them, only seen a few.
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