mine is similar, and surprises everyone the way it runs.

 

Not sure what valve seals my mechanic used bit ill do a leak down and see how the rings are before I get into heads

 

Combined with the relatively low compression of the L82, and a healthy initial and advance timing curve, it can really be a great cam. It is very close to the Crane Energizer I installed in my L48. My Energizer had .454/.454 but with shorter duration of 216 @ .050" and tighter lobe separation. It was a VERY snappy performing cam and with the rest of my setup was a thrill to drive.

 

Think carefully about "just $500 more for high-performance heads" - $1000 for the heads, $150 for the rockers - which likely won't fit under your stock valve covers - new pushrods (plus buying or borrowing the tools to measure). The intake manifold is a low-rise aluminum dual-plane - not bad, but not really well-matched to the port size or flow capacity of the heads. You'll need a good dyno tune as well...which is not easily found for a Q-jet these days. This is before the other upgrades like headers, exhaust, etc. really required to maximize the capability of the heads.

This is before talking about upgrades to the chassis, suspension and brakes required to make use of the power. It ain't all about the engine

If you have the money and want the power, a head swap is great - just make sure you count all the costs.

 

Yes it starts adding up I already have the headers elderbrock valve covers ehaust etc it just might be easier to get my original heads redone and all the good stuff they do to it prob a lot cheaper as well

 

Depends on your goals and budget. Rebuilding stock heads will be $500 plus. End result you still have stock, iron, low compression "smog" heads and zero power gains. If you would like more power these are a bolt on and really will add around 20% power across the board. They use factory components and port size on your intake will not be perfect but will result in very little power dropoff. That L82 intake is actually pretty good. Best part is they are all new, you order them, when they arrive you unbolt yours, check, and bolt on the new heads, 1 day job. You already have the exhaust and these rockers fit under stock valve covers. You will need new head bolts and head gasket set either way. In my opinion a 20% power increase is worth every penny of $500 (quite possibly less if your heads have issues) if you can swing it financially and your leakdown test and cam are good.
Unforeseen costs you could very well run into with used heads with 80,000 miles on them.
Magnaflux (could be crack causing smoke or discovered upon magnaflux) 333882 heads are notorious for cracking.
Need new springs? (after 40 years and 80,000 miles) YES
Need new guides?
Need new valves?
Need new seats?
Will they get a three angle valve job?
Are your studs good after 80,000 miles? (They wear too)
Are the rockers worn or cracked?
Are the rocker ***** worn or galled?
Will the OEM rocker nuts stay in adjustment after remove, replace?

http://www.summitracing.com/parts/su...make/chevrolet
http://www.ebay.com/itm/Dart-SHP-Aluminum-Cylinder-Heads-for-Small-Block-Chevy-Assembled-127122-/200834157660?_trksid=p2054897.l4275

 

New heads or a good valve job is a death sentence to a motor with 80,000 miles on it. Any machinist will tell you that. All that "new" compression on the top end will blow right by those "old" rings. If it is a matching #'s motor, and is worth protecting, it is a lot easier and cheaper to rebuild before it "blows up". 80,000 miles on a motor that old is starting to get up there. If you did the valve seals and it didn't eliminate the smoke, you really should start looking at the whole engine.

 

There's some truth to that - typically folks develop a much heavier right foot when performance is restored. I'm not sure it's a "death sentence", but certainly the risk increases. A "big top" with big heads on an older shorblock certainly has higher risks.

 

Lots of different opinions on here

 

Any way you go #1 is a compression test, # 2 is a leakdown test, Is your idle oil pressure good? Does it leak anywhere? Many of these motors run 150,000 miles without issues. Good luck.

http://www.superchevy.com/technical/...r/viewall.html

http://www.superchevy.com/technical/...g/viewall.html

 

It's got a small leak at the timing cover I e tried to fix it but hard to fix this one lol oil pressure is good according to the gage I should get a second gage

 

Opinions come from experience - different experience, different opinions. I do a lot of tops, upgrades and engine builds making < 1.4 HP/CID - so I tend to be more on the conservative side, and I'm always conscious that folks have a budget. I also tend to think very holistically, as I believe Corvettes need to go, turn and stop...not just go

Other folks come from racing experience where they're building high-horsepower, high-dollar engines and they've seen in that arena what happens to anything other than the very best racing parts - false economy gives bad results, and they've seen it happen over and over.

Both valid - ultimately you need to decide what you want to do.

 

really great prices on the Ebay heads !

 

The nice part of working with an L82 is it has a forged crank, forged rods, forged pistons and a 4 bolt main block. This bottom end will handle a lot more HP than an L48. If your suspension, brakes and driveline are in good condition there is zero issues with bumping your power up about 20%. You have a lot of info. Only you can decide what fits your needs, wants, driving style and budget.

 

I'd just overhaul the heads you have ....by an expert machine shop.

 

Now u guys got thinking of the bottom end how it's going to be affected by if I decide to rebuilt my heads or buy new ones as it will be nice and tight up there how is the bottom end feel. Will a leak down / compression test tell me what kind of bottom end I have

 

At 80K miles, it really has nothing to do with the components - blocks, cranks, rods (bolts are a weak aspect) and pistons typically don't fail - bearings fail - sometimes taking those components with them. The bearings supporting a forged crank aren't in any better shape than those under a cast crank after 80K miles.

There's really no way to tell the condition of the bottom end without tearing it down...and once you start down that path, bring money.

Any GEN I SBC with 80K miles on it is tired; how tired is really impossible to tell.

 

It depends on how well it was cared for up to it's current mileage.

(I'll keep this short), I bought a former Allison dealer's Chevy 3/4 ton , 350 4bolt original engine @ 147,00 miles. At aprx 160 thou the cam and lifters were gone. New; cam/lifters, timing set, rebuilt heads, new oil pump, alum intake and small AFB carb, headers and duals.

Ran like a champ, got great mileage too. I was not easy on it at all- I ran it very very hard, and hauled 1/2 to 1 ton+ - sometimes 6 days a week. It would hit 60 mph entering the interstate with over a ton in the top of second gear.
Wore out the T400 @ 171 thou and replaced it. It went over 200 thou and made it to a forth owner before he hurt it racing another buddy's truck. It never smoked or used oil.

Your engine's lower-end is probably fine .. but there's not any easy way to tell. I would do compression and leak-down tests. If you get into the engine inspect the cam and lifters closely, but definitely pitch the timing set and oil pump for new parts. $0.02

 

My brother ran his 1985 chevy 3/4 ton 285,000 miles. He got it from a friend at about 100,000 and drove it 15 years running a produce store in Florida. He hauled a trailer to and from market and farms daily usually pretty loaded. Engine was never opened up. He sold it running to his daughter that dropped the trans @ 315,000 and junked it. This is the exception but 80,000 miles is not a death sentence to a Gen 1 SBC. With the above and would for sure change the timing set. If the pan is dropped to change the pump check a couple rod and main bearings while it is open.

 

some people can drive a car 300,000 miles and you would think it is a new car,others can drive a car 10,000 miles and completely destroy it