Hello I have a late 1986 corvette with 205xxx miles on it! I was thinking about just putting all new gaskets on it including head gasket. And a new timing chain. The car does not smoke with 20w 50 in it but if I go thinner It makes clicking noises I think maybe the valves. But anyways I dont have money to rebuild it right now so that is what I was planning on doing. You guys and ladies think its worth it? Will it run or performe better?

 

check northern auto parts for a engine kit. I did a ton of rebuilds like that as a kid and bunch in claimer hobby stock cars. Good luck

 

Timing chain is a good idea, and valve springs and valve seals too. But I don't see any point in doing head gaskets if there's no problem with them.

How does it do on the compression check?

 

If it isn't broken, don't screw with it. (Or something like that)

I have 212,xxx on my 1985. I put on new AFR heads about a year ago which required new gaskets. If you car is running fine, I would let it be. If you don't abuse it, you should get a lot more miles out of it.

Just to put on new gaskets you would be looking at $60-70 dollars for head gaskets, new head bolts $55, thread sealer for bolts $8, intake gaskets $11-15, exhaust gaskets $15, valve cover gaskets $15-30, runner gaskets for plenum $10-15. Timing chain $30-70 (gasket may or may not be included with the set). And with an 86 I think you will have to have gaskets for the EGR pipe. And then when you start taking things apart, figure that you will have to replace a sensor or two and some of the electrical plugs ($20-120). Antifreeze $20.00.

Now the great question, do you have the ability and experience to tear into your car and put it back together, time the vavles, drop in the distributor and set timing? If you don;t and have to have a shop do these things you are looking at BIG $$$$$.

Just putting new gaskets won't prolong the life at this point. Save you money for the mods you want to make and start stock piling parts.

 

I havent checked the compression yet but what should it be at? Just a ball park figure?

 

Oscar,
adjust the valves and change the valve cover gaskets. leave the rest alone.
But the big thing is the timing chain.
the big gear has nylon teeth so it's quiet. These teeth wear and reduce the strength of the teeth, and they shear off.
The problem isn't the gear, it's the valves.
When the gear strips, all of the valves will hit the pistons.
all of the valves will have to be replaced. If that happens, all of the valve seats will have to be cut, the valve guides will have to be cut and replaced, and the exhaust valve seats will have to be cut out and replaceable seats installed, because once you go through the surface hardening, the head is soft again, an you will erode the head with unleaded gas. IT WOULD BE CHEAPER TO BUY REPLACEMENT HEADS FROM ME !!!! HAHAHA
go ahead and change the timing gears, and press on.
use 10-40 W oil, and add 2 quarts of synthetic oil every oil change and when you add oil in between changes, use synthetic.
start saving your money, and at 205,000 miles, it's more cost effective to buy a different engine. don't waste your money on the engine you have. It's nothing special. I know, I have been into 6 of them, and they are just nice basic 350's
buy a good running low mile engine that you can hear, that's still in a car or truck, Change the cam, buy a new one like what's in your car, and put your TPI on it , and keep going.
The best thing to do is fix things as they break, don't let the list add up.
If you do, your car will be a junker, and a cavalier will sound good .
see ya, CHRIS

 

An 86' would be a simple crate motor drop in if you not looking to get into building a custom engine. GM has a motor for your needs.

Compression for that model 350 should at least be 125-140. If you have that much for its mileage and age.....

 

bump

 

On my '88 with >170k miles the average compression was 112psi on the 1st stroke and 169psi by the 4th stroke.

 

I wouldn't bother opening it up unless something goes on it. if you open it up, you might as well just rebuilt it since you are doing most of the labor anyway without the same results as getting a newer engine.

Anytime you tear open your motor, go ahead and upgrade/redo whatever is in there if it been that long. It would be a waste to replace all that stuff, just to have something go in it one month later.. then you have to spend ALL that time AGAIN taking the motor apart.

 

Cylinder compression on my 86E with 94,000 miles was 160-170 psi on all 8. New engines get close to 200 psi. I would check the compression to see how healthy the engine is and follow the previous advise.

 

[QUOTE=coupeguy2001;155811348



When the gear strips, all of the valves will hit the pistons.
all of the valves will have to be replaced. .

I'm not so sure about this statement.Maybe on an LS1,but an L98 should be a non-interference engine.

 

JMO, but at that mileage, you're better off just driving it. You're pretty much at the all or nothing point. There's a 50/50 chance you can get another 50k without touching it, or it could go tomorrow. Either way it will cost about the same to go through it unless you blow it up by hammering it after you notice serious problems.