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the 77 Nova is undergoing heart surgery soon and i'm debating on the donor. back when i owned her in '92 she had an inline6. this time around i want to upgrade that to at least a 4.3 v6. those to me seem like the engine it should have come with from the beginning. and its cheap to come by and build up. eventually as money gets right and kits become available i want to put in a LS 6.0.

but what are the thoughts of a Vortec 4.3 200hp daily driver-able 4th gen Nova?
 

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Nothing wrong with a straight 6 engine. Never was a big fan of the 4.3 V6. It always seemed very inefficient. Its power band is not very linear as well. Why not stick with a straight 6. Take a look at the GM LL8 6 cylinder. They are super cheap in junkyards. Very powerful engine in NA trim. People have adapted the twin turbo setup from Toyota Supras on them since it is suspected they were developed with Toyota's help. But just some simple bolt on parts and a good aftermarket tune you can be over 300hp.

Jake
 

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well back when i owned it the first time around it had the inline 6. i was okay with it because i was a kid and it was my first car. this time around i bought it back the engine was already gone. it was just a rolling project without a engine/trans. i have found many 4.3 vortecs at pullaparts that i can buy for $300 or so and access to parts. i just never driven a car with a 4.3 before and unaware of the reliability. but its basic 200hp vs my inline 6 back in the day with 75-80 hp... i believe the vortec 4.3 wins out. i'm not talking about the new gen inline 6 found in trailblazers because i wouldnt go through the fab efforsts to make it work in my 77 Nova. i wouldnt mind having that one in my 68 C10 though. but just to get my 77 nova back on the road and i think a 4.3 v6 fits it better. i just wish someone else has done it before so i know what im diving into
 

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My objection to the 4.3 is based upon the failure in math in the design part of it. You can not just drop two cylinders. That was obviously a marketing guy dreamed that up. The engine runs on four cycles Intake-Compression-Power Stroke-Exhaust. Three doesn't divide into four. That remainder is why a V6 vibrates and an in line doesn't. You have two dead cylinders that are causing the motor to vibrate.

A Harley twin (and my John Deere two cylinder tractor) are half of a four cylinder engine. That means half the engine is missing! Believe it or not Harleys vibrate when they run! The V12 Rolls-Royce engine will idle so smoothly that you can balance a coin on edge on their valve cover. A V16 Cadillac engine would idle as smoothly if you find one running in a museum. All are multiples of four which match the four stroke engine cycle.

My Ford V-10 Triton motor has bearings bigger than the main bearings that support a counter weight shaft that spins in the lifter valley to compensate for the two missing cylinders. With in-line engines you have one cylinder per crank throw spreading the number of firing cylinders into 360 degrees, so there is no crankshaft flexing due to missing cylinders. Buick had a great in-line eight cylinder. Most big semi trucks are powered by a big displacement four banger or an even bigger in-line six, some have a V8 (though they are not much bigger than the sixes), and few even have a four turbo V-12 but they are not cheap and as such are very rare.

The factory tried offset grinding the crank, counterweights in the engine and odd firing to smooth out the vibration. adding two cylinders cures the problem.

Buy a V8. A 180 horse 305 can be had for the price of the scrap metal in a U-pick yard. That is usually $50 to $75 dollars. The difference in price to rebuild it is minimal.

Big Dave
 

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if considering the swap - the frame towers and rubber cushions from an 80/81 Camaro (or 78-88 G-body) must be used along with the Camaro fan shroud (the 4.3L is a descendant of the 200 and 229 which replaced the third gen inline six which was restricted 2 truck/van use after 1979); also if using the serpentine belt drive the power steering lines from an 89-92 Caprice (taxicab package) must be used along with the A/C hose from a 75-77 Buick Skylark with the 3.8L (I have a stock TBI 4.3L (RPO LB4) in a 92 S10 Blazer with over 351,xxx miles)
 

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well back when i owned it the first time around it had the inline 6. i was okay with it because i was a kid and it was my first car. this time around i bought it back the engine was already gone. it was just a rolling project without a engine/trans. i have found many 4.3 vortecs at pullaparts that i can buy for $300 or so and access to parts. i just never driven a car with a 4.3 before and unaware of the reliability. but its basic 200hp vs my inline 6 back in the day with 75-80 hp... i believe the vortec 4.3 wins out. i'm not talking about the new gen inline 6 found in trailblazers because i wouldnt go through the fab efforsts to make it work in my 77 Nova. i wouldnt mind having that one in my 68 C10 though. but just to get my 77 nova back on the road and i think a 4.3 v6 fits it better. i just wish someone else has done it before so i know what im diving into
I have had many s10 trucks with the 4.3 and they are very reliable. As long as you do away with the spider injector. They are just a 350 with 2 cyl chopped off. The motor mounts are the same as a 350 and bolt to many transmissions. This is the way I'm going. Summit has a cam, 4 bbl intake and headers for the 4.3. So I say if you want it, do it. That's what I'm doing and I think it will be a drastic improvement over the inline. Yea it's. It's not as balanced as the inline but it's a good platform to have fun with until you can do the ls.
 

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My objection to the 4.3 is based upon the failure in math in the design part of it. You can not just drop two cylinders. That was obviously a marketing guy dreamed that up. The engine runs on four cycles Intake-Compression-Power Stroke-Exhaust. Three doesn't divide into four. That remainder is why a V6 vibrates and an in line doesn't. You have two dead cylinders that are causing the motor to vibrate.
Not exactly.

A V-6 can be quite smooth; the first thing you do is to put the cylinder bank angle at 120 degrees instead of 90 degrees. 90 degree bank angle is perfect--for a V-8. Four-stroke engine needs 2 revolution of the crankshaft, = 720 degrees of rotation. 720 degrees of crank rotation / 8 cylinders = 90 degree bank angle.

720 / 6 cylinders = 120 degree bank angle. However, you can also build a smooth running V-6 using a 60 degree bank angle, IF you offset the rod throws on the crankshaft to compensate. Not as elegant as a 120-degree bank angle, though. There's plenty of examples of 60-degree V-6 engines, including many from GM themselves--starting with the 1960 GMC gasoline V-6 as used in light, medium, and heavy trucks.

Problem is, the Buick, and the "big" Chevy V-6 have a 90 degree bank angle, both engines have had some crankshaft trickery, but even with offset rod journals, there's vibration problems that need balance-shafts to "correct".

There is no way on Earth that I would go through the time, money, effort, and enthusiasm to slap a V-6 into an X-body. It's going to take the same amount of work as a real engine, but with no payoff in power or reliability. God bless the 4" bore, and 4.125" bore SBC.

OTOH, the Trailblazer "Atlas" inline 6 is quite a nice engine, but it'll likely need the matching transmission plus the total computerized emissions/fuel injection/ignition system to make it work right.
 
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