89Formula305tpi

I have done some searching and haven't found a real definitive answer. Who has positive seals on both the intake and exhaust for several years and has good luck with them?
Is it true that positive seals will starve the exhaust guides for oil?
And I was wondering what kind of seals the LT-1's have because as far as I know they don't have a smoking problem. Do they use all positives?
Thanks

Damon

That's a good question. I'll say that I usually use posi seals on the intake and umbrellas on the ehaust for exactly the reason you describe- I don't want any chance of starving the exh guide for oil. It's a combo that has worked well for me. Most oil consumption seems to happen on the intake side anyway since it's under vacuum all the time from the intake port, unlike the exhaust.

However, most aftermarket heads come with posi seals on both intake and exhaust and I don't hear many people complaining about worn out exhaust guides because of it.

LT-1 heads I'm not sure about. I think they have posi seals on both intake and exhaust but remember that the factory can make minute changes to the seals and whatnot that might not be obvious to the naked eye.

ede

i use positive seals and o ring seals both, never had a problem and i've stuck them on more than one set of heads. i don't like ot use the umbrella seals.

89Formula305tpi

ede,
How many miles/years have you gone with the positive seals on the exhaust? Have they held up well?
Thanks

ede

used them since the 70s on one thing or another. have them on my truck that i just trashed in the snow, 23,000 miles on the rebuild.