valves burning up?

[Michael Fornal]

Kinda carry over from my other thread, but I figure more people will read a new thread than one bumped to the top with replies. Word? Yeah.

If I ran open headers on a daily driver, not that I would, because it is illegal and wrong!, but IF I did... would the valves burn up? Dude up at my job seems to think they would, but I don't see why. I don't see how it would be harder on them whether the headers are connected to a pipe or not.

I can see if you just ran with no exhaust whatsoever, but I dunno. Feel free to shed some light in my general direction!

[ July 31, 2002: Message edited by: Michael Fornal ]</p>

[Blue Flame V6]

Yes you would burn your valves. What happens is cold air comes in through the headers and hits your valves and they are around 1500º the air is around say 60º they contract faster than your heads and wala there screwed up.

[Michael Fornal]

So would a couple of small straight pipes rememdy that situation? And if it would, how much would that cut off on the sexy round the open headers make?

Thanks for the reply.

[Blue Flame V6]

that wont work either. YOu have to have some sort of block on the exhaust like a small glass pack would work on each. Cuz even with a full straight pipe it happens just not as likely.

[viper98885]

What Blue Flame is saying is correct, but you have some options. First would be to replace your stock valves with a set of Manley's or another high performance racing valve. You would more than likey have to have them custom made for your application, which would be pricey, but if you either have a lot fo extra money to blow or are wanting to make this an all race engine, go for it.

[ July 31, 2002: Message edited by: viper98885 ]</p>

[Arctc Wolf]

A good way to keep the sound you already have would be to run the headers w/ the y-pipe, a 3" piece of pipe where the cat is supposed to be, and a slp loudmouth exhaust. personally, I'd get a 3" cat thrown on and have the loudmouth after it. the resonator and cat will prevent any cold air getting up to the valves. Or, you could get inconel exhaust valves. they don't soak up as much heat as other valve types do and are less prone to warping.

[Michael Fornal]

Thanks for the replies, guys - muchos appriciated.

Viper, what would you consider pricey?

[WickEdSix9838]

If this is true....then how the hell do race cars run open headers w/o burning the valves??? true they will burn if you have no headers or type of exhaust off the exhaust port....but with that much pipe off the head, its too far for the cold air to go all the way back to the valves

[Arctc Wolf]

depending on the type of car you're talking about, I can explain. if you mean drag cars, they're basically re-built after every 2-3 races, and compared to everything else, a valve isn't a bit ticket item. if you're talking about cart of nascar, they run at higher rpms for most of the race, unlike street driving in which you're having to stop sometime and let off the gas, allowing cooler air into the headers.

[viper98885]

<blockquote>quote:</font><hr>Originally posted by Michael Fornal:

Viper, what would you consider pricey?<hr></blockquote>

Custom valves would run about $500 for stainless steel valves. Next problem would be finding a company that would make V6 valves. It would take some research to find out the exact dimensions of our stock valves (which wouldn't be hard) and then find out what kind of SB Chevy engines use anything close to it. In the long run, it may not even be possible to get a set simply because there wouldn't be anyone out there to manufacture them.

[Michael Fornal]

Thanks for the reply. I am doing the smarter thing now, i think - putting the money to pay towards my credit card, instead.

I am so deep in the hole on this car, too(9500 owed on a '96). Sucks for me.. can't wait to pay it off and drop it for a '00 T/A.