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Question about head reconditioning.
Date: April 10, 2018 08:31AM

I've been lurking here for a while. I have a profile over on corvairforum because it works better on my phone through tapatalk, but this place seems to be way more active. I have a set of 98hp heads that I was going to clean up in order to replace my 80hp heads that are in terrible shape. The cooling fins on the right bank are almost non existent from rodent urine. It drives fine as is and I drove it daily in two hot summers but I cant imagine its staying as cool at it could be.

My plan was to:
Steam or scrub clean
Deflash Fins
Clean up casting marks in ports
Lap valves
Check out the guides
Replace springs
Replace Valve seals

In the searching I have done I have seen a lot of people say that replacing the seats is absolutely mandatory but I wasn't sure if that was for performance builds which this is not. Also, can anyone point me in a direction as to what head gaskets would be best to use. I may go thicker to retain the 8:1 compression but I suppose i could use the extra 4 hp of 9:1 if I have to. Thanks! Happy to be part of this Online Corvair community.

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Re: Question about head reconditioning.
Posted by: MattNall ()
Date: April 10, 2018 08:53AM

Welcome to the CCF!

Your plan sounds fine to me..

As far as Seats.... check them closely and decide...

Age is your enemy.... but if you can't find anything...and you do your own work... run them!

Labor is the expensive part of dropped valve seats..





MODERATOR
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..............................110-PG.................................................Webered-Turbo

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Re: Question about head reconditioning.
Posted by: vairchet ()
Date: April 10, 2018 09:54AM

If you're not the kind that 'run it hard, then put it away dirty', I'd follow Matt's advice, install 98hp heads (cleaned up of course) on your 80hp engine. As for head gaskets: Use the standard steel crush gaskets. Don't worry about extra compression. I've assembled plenty of similar combinations such as yours without complications. With minor alterations to distributor timing, you'll still be able to run regular grade gasoline.

Chet in Ramona

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Re: Question about head reconditioning.
Posted by: TerribleTed ()
Date: April 10, 2018 01:19PM

Non 140 and non turbo heads are not from what I have seen very prone to dropping valve seats. I have seen 3 dropped seats (and 2 of them were in one engine) in non 140 engines over 30 years of working on these cars. I have seen many in 140 engines (at least 15 cases). If the seats are not loose and the aluminum around them in the head is not all corroded to heck (if it is a better head is a good idea), do your basic valve work and run the piss outa themsmiling smiley

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Re: Question about head reconditioning.
Date: April 10, 2018 02:39PM

Thanks gentlemen. I wont lie, I often drive it fairly spirited. I mean in reality you kind of have to in order to keep up with traffic. The current heads (engine) had been sitting since 91 and had a frozen valve that I got unstuck without pulling the heads off and that's been absolutely fine, even in the middle of a hot summer, so i would hope that any pair of fresh heads should be a welcomed upgrade.

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Re: Question about head reconditioning.
Posted by: Timothy Shortle ()
Date: April 10, 2018 02:56PM

I am not sure where you are located but stay out of Arizona. The last 2 valve seats I dropped were both in AZ. Once driving my Rampside PG thru Kingman and the other in Flagstaff. Once coming from my house in SD (not South Dakota) and once coming from the GWFBT in Palm Springs. In other words, new valve seats for me before I embark on a long road trip. YMMV (but I don't like being on the side of the road hundreds of miles from home).

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Re: Question about head reconditioning.
Posted by: Frank DuVal ()
Date: April 10, 2018 06:24PM

I've seen then drop out of 80, 95, 110, 140, 150 and 180 heads. After 50 years, none are immune to dropping. And I started seeing them dropped, even in 80s and 95s back in the late 70s!eye popping smiley


Heat them up going up a long grade, over a mountain top, then suck in cold mountain air on the down slope. What's that noise?smileys with beer

Frank DuVal

Fredericksburg, VA

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Re: Question about head reconditioning.
Posted by: steve c goodman ()
Date: April 10, 2018 06:45PM

I was seeing 1960 80hp seat ring failure in 1962. Not often but once in a while. Early turbo happened too while new.

Almost always the story was the same "it was running good when I shut it off".

Obviously the implication is the engine was shut off too hot. Still true today whether 80hp or 180hp.

But a good pair of heads with clean air holes and good fuel and ign and good driving habits is certainly worth a try.

best wishes, Steve
Rear Engine Spec. Inc. Golden, Colo.

1962 spyder 3.0L turbo---1965 Crown V8
1967 monza 110/4---1968 monza 110/4
1971 amante gt 110/4
CORSA/RMC/PPCC

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Re: Question about head reconditioning.
Date: April 16, 2018 09:40AM

Sounds like a good hot engine sucking in some cold air is a recipe for disaster. I'm in Central NJ and although I do hit the mountains of PA occasionally, I usually stay local or near the southern shore.

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Re: Question about head reconditioning.
Posted by: jcorvair ()
Date: April 16, 2018 09:02PM

Smog engines too can be hard on seats. I dropped two in close succession on a '69 smog engine. One on one side, replaced the head and dropped one 60 miles later on the other side. Replacing the seats with deep seats will give you the confidence to drive anywhere, anytime.

James
Maple Ridge, BC

2013 Hyundai Santa Fe Turbo
2013 Hyundai Elantra (daughter's future car)
2009 Silverado HD Crew Cab 4x4 (for haulin cars, trailers, fifth wheels, quads, etc.)
2013 Victory Car Hauler (enclosed)
2015 Polaris 570 EPS
2016 Polaris 570 SP

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