I have a 1976 Stingray 350 (barn find). Bought it about a month ago. It had been sitting for about 6 years prior to my purchase. Towed to a friend's garage yesterday, replaced corroded fuel pump, new oil and filter, removed old gas from the tank, and got it started... only to hear a horrible knocking.. Friend is doing a little more digging today but assumes the main bearing is toast. His first suggested was to get a turn-key crate and drop it in.

On one had I like the idea to get a crate motor, maybe with a little more power then the original 350 is known to have. I have read a lot of good reviews about the ZZ4 from people here.

On the other hand, before I purchased the car I made sure that it was the original motor, frame, ect for the fact that I wanted an original Stingray.

So.. Looking for some guidance/knowledge. Should I go 'out with the old and in with the new'? Or should I get the motor rebuilt.

Keep in mind that I'm only 26 years old, I am trying to stay as cost effective as possible and plan to keep the car.

Thanks.

 

If you want power and it's an original engine, rebuild it but you will need some skill. If your a complete newbie (with no mechanical experience)you may want to go crate engine and save the numbers matching engine but take note of the core fee if you plan on keeping the original engine.
None of this is hard, but it will take time and a lot of questions, pics, posts, guidance, maybe a visit from a forum member to your house and a lot of beer!!!!
Many have done it, you can too if you commit and have a few bucks!

A ball park price for you to completely rebuild the engine with all the machine work, new pistons, refurbished heads, crank shaft ground and new cam will set you back about $1500-1800 with mild performance parts and you assembling the motor. Crate engine is $2000 + core + shipping. 350 engines are a dime a dozen. If you bring a knowledgable mechanic with you. You can find a nice used 350 for $500

 

Buy a crate motor, bag the original and store it.

You can buy a nice 400 HP aluminum head late gen 1 small block crate motor long block for $3500. For that you get a 1 piece rear main seal, 4 bolt mains, a hydraulic roller cam, aluminum heads and 10:1 compression that'll run fine on 91 octane.

Unless you are restoring the car to original there is no good reason to rebuild a 1976 350.

 

What do want to learn? How to rebuild an engine, or install an engine? You can spend the mentioned $3500 for a crate, or $1500 for a machine shop to return a short block to you for your completion. You won't need any specialized tools to assemble it. Parts for medium performance SBC's are cheap.

 

I just went through this exercise-good points and advice above^. If the car is a base 350 and an Automatic, I would probably just go with a crate engine and save the old block. For $3,500 you can get a 400+HP crate engine which is a great deal. My 78 C3 is a pretty much original L-82 4 speed with 3.70 gears and 66,000 miles when i decided to keep the OEM L-82 with all numbers matching. I had the bottom end professionally rebuilt (Bored .030-355 now) and assembled everything else myself using top notch parts such as a retrofit roller cam, JE forged pistons/rings, AFR 180 heads, felpro gaskets everywhere, melling oil pump, AC delco fuel pump, comp cams roller tipped rockers etc PLUS a new balancer, New Ram Clutch kit, new Motor mounts, new pushrods, resurface flywheel, balanced rotating assembly including flywheel and clutch etc-$6,000. Engine is FAST and easily a match for a crate 383 AND looks pretty much stock with the L-82 intake and air cleaner assembly.

If none of that matters, crate all the way.

 

How many miles are on that original 76 engine?

 

I wouldn't say I am a complete newbie but can't claim to have any rebuild experience.

I guess the good thing is I'm in no rush to make a decision or to have it on the road (though the sooner the better). I want it to be a functional cruiser, no show car so I may lean towards the crate.

 

95K on the original. I was expecting issues to come up with an aged 350, just not when I first got it started.

 

With 95k, I would expect the cylinders need to be bored at least .030 and that means the rebuild cost are going to increase dramatically. If your buying new pistons, why stop there, why not go 383? Before you know it, the rebuild will be up to $5k in a heartbeat.
Does anybody know if the 76 is a 4 or 2 bolt main engine? If it's only a 2 bolt main, I would say that would limit the HP on the rebuild.
My best advice would be to price out your different engine options and don't do anything in a big hurry.

 

Thanks for the advice.

 

Pretty much all L-48 (base motors) from the early mid 70's to 82 are 2 bolt mains. Only the L-82's were 4 bolt mains. 76 base motor-l-48-almost definitely 2 bolt main. There are instances where the owner has taken apart an L-48 and it had a 4 bolt main and the reverse for the L-82's but that happened rarely when GM ran short on a particular block type. My 78 L-82 is a 4 bolt main.

 

The 2 bolt main block is no limitation to building a more powerful engine. I'm using the original 2 bolt main block in my 77, converted to a 383. It makes enough power to run 12.1 at 110 in the quarter. I have 200 runs on the bottom end and its holding up just fine.

 

Points for not using the original motor:

The heads are junk for performance use. These are full-on early emission heads, the base 76 350 made a whopping 180 HP.

The heads are cast iron so you have to run 1 point of compression less than with aluminum heads. You're throwing away horsepower, the more compression you can run the more power and torque you have from idle to redline.

It uses the potentially leaky 2 piece rear main seal

It uses a flat tappet cam. A retro fit hydraulic roller for your 76 350 is $700 for just the cam and lifters. If you use a flat tappet cam you're just asking for trouble.

If you decide to rebuild an engine yourself, do yourself a big favor and use a very late version of the 350. But, honestly you can't build it for what you can buy one for.

 

I agree, "don't do anything in a big hurry", do some research, decide what you really want and how you are going to use the car. I do disagree on 2 bolt 4 bolt blocks though, that shouldn't be your deal breaker for rebuilding what you have. A 2 bolt block will easily support a mild to mid performance small block especially for cruising. It won't cost anything but your time to tear down what you have and do a preliminary inspection of the major parts to see what is useable and rebuildable. Again you need to know what you want when you are done. Talk to your local machine shop and parts house, build it on paper to see the $$$ actually spent. This is all part of the fun for lots of us. Good luck!

 

Thanks, that is the process I'm starting now. Reached out to a couple machine shops and trying to get accurate prices for crate motors/parts.

 

Right now in the C3 for sale section is a never fired new ZZ4 crate engine for $2800.

 

after 34 years of driving, my original engine spun a bearing about 6 years ago and I decided to install a new GM Performance crate engine. I still have the original engine, in my garage, covered and will, someday, have it rebuilt and improved.

So you can do both!

 

What crate engine did you go with? And how do you like it?

 

In 1997 my once rebuilt L-46 was getting a little tired. I decided on a ZZ 4(at that time there were not as many crate engines available as there are now). The ZZ-4 has similar power & torque as the factory L 46 and runs fine on unleaded fuel. My '69 is manual so a new flywheel was required for the 1 piece rear main block. Drive 2,000 - 3,000 miles a year. Still runs strong with no problems.

 

A GM crate motor is NOT the same as a generic crate motor and they also cost MUCH more than standard crate motors. They are also rated at GROSS HP like your L-46 was so not surprised that you found the power to be equivalent. I would imagine that a 97 ZZ4 was rated at about 325 Gross HP.