The Beast in Me...

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L31MaxExpress

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It is not a mythical beast of legend for me. I have an 8.1 in my 1983 G20 van and have a 2nd 8.1 I just picked up to swap into my 1999 Tahoe.
 

94burbk1500

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Big blocks just aren't practical, especially when you can get just as much power out of a smaller and lighter engine that gets twice the gas mileage. My family doesn't even use big blocks in our race cars, the biggest we run is a 430 and it puts out 700+HP, naturally aspirated.
 

L31MaxExpress

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Big blocks just aren't practical, especially when you can get just as much power out of a smaller and lighter engine that gets twice the gas mileage. My family doesn't even use big blocks in our race cars, the biggest we run is a 430 and it puts out 700+HP, naturally aspirated.

HP is one thing but TQ is another. You will not come close to getting big block torque out of a small block. 6.0L does not come close to 2x the mileage of the 8.1. I am seeing 14-16 mpg in a brick of a G20 Van from an 8.1 with a moderate sized roller cam in it and I have barely touched the tuning. That is also running a TH400 with no lockup and 3.08 gears.
 

94burbk1500

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HP is one thing but TQ is another. You will not come close to getting big block torque out of a small block. 6.0L does not come close to 2x the mileage of the 8.1. I am seeing 14-16 mpg in a brick of a G20 Van from an 8.1 with a moderate sized roller cam in it and I have barely touched the tuning. That is also running a TH400 with no lockup and 3.08 gears.
Well if torque is what you're after, why even mess with that monstrosity when you could get a diesel? Also, the torque numbers are pretty damn close between a 454 and a 6.0, I'm not familiar with the 494 specs though.
 

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Well if torque is what you're after, why even mess with that monstrosity when you could get a diesel? Also, the torque numbers are pretty damn close between a 454 and a 6.0, I'm not familiar with the 494 specs though.

A Vortec 454 makes ALOT more torque, especially in the lower rpm than a 6.0L. The 6.0 does not reach peak torque until it is close to or over 4,000 rpm depending on the year. The Vortec 454 reaches peak in the 2,800-3,200 rpm range. The older TBI 454 puts down its torque peak at 1,600 rpm and it matches what the 6.0L at that RPM.

I am not a diesel fan especially the newer electronically injected garbage ones. The newer they get the more of a maintenance nightmare they are.

The 8.1 with a stock tune is 455 ft/lbs @ 3,200 and picks up 50-60 ft/lbs of torque with a decent tune. Once you swap on some headers, port the intake manifold, put a mild cam in it, it easily cranks out 550-600 ft/lbs.
 

L31MaxExpress

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The 8.1 in my G20 van has the GMPP 454/502 HO camshaft. The one going into my Tahoe has the Mercruiser 420 HP 496 HO cam. In testing the 420 HP engine made 450 HP on an engine dyno at 5,100 rpm with the only addition being headers and exhaust.
 

94burbk1500

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A Vortec 454 makes ALOT more torque, especially in the lower rpm than a 6.0L. The 6.0 does not reach peak torque until it is close to or over 4,000 rpm depending on the year. The Vortec 454 reaches peak in the 2,800-3,200 rpm range. The older TBI 454 puts down its torque peak at 1,600 rpm and it matches what the 6.0L at that RPM.

I am not a diesel fan especially the newer electronically injected garbage ones. The newer they get the more of a maintenance nightmare they are.

The 8.1 with a stock tune is 455 ft/lbs @ 3,200 and picks up 50-60 ft/lbs of torque with a decent tune. Once you swap on some headers, port the intake manifold, put a mild cam in it, it easily cranks out 550-600 ft/lbs.
That's all fine and dandy, and would be great for a tow pig, but LS is the way to go for a modern hot rod. Big blocks used to be the way to go for a mean street machine, but LS motors are cheap power and there's a million different options for them. I'll concede that, if you are looking fro a good motor for towing, the big block is a good choice. I'd never put one in a performance oriented setup though.
 

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Also, to be fair, a ton of drag racers take the 454 blocks and turn them into screamers for the track, but that hardly counts as BBC when the block is filled and is literally the only Chevy part in the entire engine.
 

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That's all fine and dandy, and would be great for a tow pig, but LS is the way to go for a modern hot rod. Big blocks used to be the way to go for a mean street machine, but LS motors are cheap power and there's a million different options for them. I'll concede that, if you are looking fro a good motor for towing, the big block is a good choice. I'd never put one in a performance oriented setup though.

Unless you were going forced induction, I would stay with the big block. Decent quality aluminum heads are CHEAP for the big block now. You can literally bolt together a 496 stroker with aluminum heads that would kick the hell out of anything a 6.0L could do for less $$$ than a 6.0L swap.
 
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