Head gaskets 85 vette
Thread Starter
8th Gear
Joined: Oct 2007
Posts: 8
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Head gaskets 85 vette
Been having some coolant leak from my 85 vette. On the way home one night my car overheated. Antifreeze was leaking out of the top of my resevoir bottle that was obviously full. Took it to a shop because I could not find the source of the leak and problems with overheat. The mechanic told me both of my headgaskets were blown. He seen the leak when he presurized the system. My oil looks fine and the car still starts and sounds normal. Do I do this myself? I am mechanically inclined but I have never done this job before. What am I in for? Where can I look for help? What are some, "Hey while you have the heads off you might as well do this", type of jobs? I am under no time crunch, winter is coming anyway, this is not my only vehicle. I want to make sure I make this a very dependable car for the spring, summer and fall '08. What say you? Thanks.
Tony
Tony
Pro
Joined: Nov 2006
Posts: 638
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From: Plano TX
In a nutshell, it's basically just removing a whole bunch of a bolts. Seriously, it's not bad. Assuming it's stock and you have iron heads, you probably didn't warp your heads but you should get a valve job while you're at it and have them level the mating surface of your heads.
Given how much you'll have off, you can think of other things you might want to do around performance upgrades. You could change out the cam, intake, go to headers... so on so forth while you're at it if you wanted.
Good luck!
Given how much you'll have off, you can think of other things you might want to do around performance upgrades. You could change out the cam, intake, go to headers... so on so forth while you're at it if you wanted.
Good luck!
Pro
Joined: Jun 2001
Posts: 520
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From: Elverson PA
You will be fine. Just take your time. I agree with evmlarry. Instead of trying to clean the heads, just have them resurfaced. If they aren't that cruded up w/ gasket, then I would use a straight edge to check for flatness and skip it, if I could. It will be $150 or so to flatten your heads. You could just lap in your valves to save a few bucks if you want. I don't know how much hp a real 3 angle valve job is worth, but you could do that too. It isn't that expensive.
I would get a carbide burr and clean up the castings at the least, but I always have to mess w/ everything.
Also, before you do too much, remember that the AL ....113 heads are only like $400. And they are good for at least 15 hp over the '85 heads. And they weigh about 50 lbs less. You add up the shop work, and you will be putting a couple hundred into your heads. You might as well do it to some AL heads. You might get lucky and get a flat set of AL ones that need nothing. A good source is Contemporary Corvette, Bristol, PA.
Good luck.
I would get a carbide burr and clean up the castings at the least, but I always have to mess w/ everything.
Also, before you do too much, remember that the AL ....113 heads are only like $400. And they are good for at least 15 hp over the '85 heads. And they weigh about 50 lbs less. You add up the shop work, and you will be putting a couple hundred into your heads. You might as well do it to some AL heads. You might get lucky and get a flat set of AL ones that need nothing. A good source is Contemporary Corvette, Bristol, PA.
Good luck.
Race Director
Joined: Sep 2005
Posts: 10,878
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St. Jude Donor '07
I'll be replacing the valve seals on my '85 this winter, too. My concern is that the guides are 22 years old and might be shot. If that is the case, I'll be putting the AL heads on and plugging the EGR circuit. This will require a new chip. While I'm that far, I'll have the intake & heads ported a bit. Maybe switch to 1.6 rollers. If I can get the CR around 11:1, I can pay an extra $400 for an E85 switch.
All sorts of things to consider. Start with the AL heads. $400 for 15hp is insane! (1hp per $100 is average.) Plus, as stated before, 50# less!
TPIS headers are awesome with a punched cat and Corsas. Hedman Elites are good, too.
You'll want to try porting the dams off the plenum and getting a 52mm TB. Throw a $100 underdrive pulley kit and a custom chip ($150) and you're laying some serious HP down for a winter tinker job.
All sorts of things to consider. Start with the AL heads. $400 for 15hp is insane! (1hp per $100 is average.) Plus, as stated before, 50# less!
TPIS headers are awesome with a punched cat and Corsas. Hedman Elites are good, too.
You'll want to try porting the dams off the plenum and getting a 52mm TB. Throw a $100 underdrive pulley kit and a custom chip ($150) and you're laying some serious HP down for a winter tinker job.
Advanced
Joined: Dec 2006
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From: taylor mill kentucky
If your going to go that far you might as well do new cam, heads, intake and headers. Why the hell not you will want to do it eventually anyway. I tore mine down last year and I am going to do it again this year. I wish I would have done it all at once.Save yourself some time and do it all at once. Just my opinion!
Thread Starter
8th Gear
Joined: Oct 2007
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Thanks for the opinions more welcome!
Thanks so far for the replies. I am a step closer to doing this job myself. Should I machine the original heads or get AL heads? What is a good set and where to buy? Looking to keep my vette a daily driver. Will headers make my car louder inside? Outside? Which intake to buy? Where?
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Pro
Joined: Nov 2005
Posts: 602
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From: North Bay Ontario
Tony...something to think about - you may very well have leaking head gaskets and be in for a big job, but a couple of weeks ago I had the same symptoms happen with my Grand Am and was sure I had a head gasket leak too -- I thought some more about it and decided to check the thermostat and sure enough it was stuck in the closed postion and wouldn't even open in a pot of boiling water - 10 bucks later and my daily driver is running good as new...
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
Originally Posted by williammackean
If that is the case, I'll be putting the AL heads on and plugging the EGR circuit.
Originally Posted by evmlarry
If he was to switch to the AL heads, would he have to change the intake base or at least get the center holes elongated?
RACE ON!!!
Pro
Joined: Jun 2001
Posts: 520
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From: Elverson PA
Since they fit, I would do the 113's. They are on here in the for sale section all the time. I just saw a set over there for $500, completely rebuilt.
Like I said, you will spend about $180 just having your heads surfaced. Now if you want valve guides, new springs, etc, you could end up putting a few hundred in your heads.
Oh yea, last I did it, it was $90 to flatten an AL head. It could cost more to do your FE ones.
When I am faced w/ the decision you are, I will have to get some other heads. It will just be a choice between the 113's and some of the less expensive aftermarket ones. It is also a hard choice about how much you want to spend on a 1985 corvette. You could spend $5000 on heads, intake, roller rockers, cam, timing set, gaskets when a lot of these cars are selling for less than that.
Problem is what other car can you get? I wish they made more of these cars in stick. That would be infinitly more fun. I would be more attached to it then.
Like I said, you will spend about $180 just having your heads surfaced. Now if you want valve guides, new springs, etc, you could end up putting a few hundred in your heads.
Oh yea, last I did it, it was $90 to flatten an AL head. It could cost more to do your FE ones.
When I am faced w/ the decision you are, I will have to get some other heads. It will just be a choice between the 113's and some of the less expensive aftermarket ones. It is also a hard choice about how much you want to spend on a 1985 corvette. You could spend $5000 on heads, intake, roller rockers, cam, timing set, gaskets when a lot of these cars are selling for less than that.
Problem is what other car can you get? I wish they made more of these cars in stick. That would be infinitly more fun. I would be more attached to it then.
Racer
Joined: Oct 2004
Posts: 409
Likes: 2
From: Toronto Ontario
I also recently blew a head gasket. I am reinstaling everything this week. This is a big job, but not too difficult if you plan it right and take your time, document the way things came off and where they go. They say it takes about 2 weekends. start taking off the TPI, then fuel rails, some brackets and hoses, then exhaust manifolds. Take off the distributor, and remember where it's pointed so you can put it back the same way it came out, if you don't the you'll be finding top dead center. Take the intake off, and then the heads. I had to spend several hours cleaning the heads and bolts (I'm reusing the same ones). I also rethreaded the engine block. If I were you I'd consider better heads ('86 or later, or aftermarket), send them out or learn how to modify them if you're looking for an improvement. In my case I'm going with a new edelbrock intake, and new 1.6 roller rockers, since I had the stuff off anyway. Good Luck!
