big blocks...

[leftybass209]

Originally Posted by davepl

Because people pick the cam third from the bottom of the list in the Summit catalog, run no choke, no heat stove, no thermac, no heat riser, and then compare it to the LS motor with all of it's warmup equipment (mostly software though!) and complain it's not as driveable.

A big block with a factory-calibrated Q-jet drives like an LS3, it just gets a lot worse mileage. It's when kids monkey with them and rip off all the pieces that don't make power that you wind up driving it with two feet so it doesn't stall, and that gives them a bad name.

Properly set up, they should run perfectly.

So many people struggle to understand this. The factory NEVER spent money on something not needed, and they still don't. Why would they waste money on a heat riser if the engine warms up fine (comparably) without it? It costs them $$$$ to install those on every engine that was equipped. Stripping that stuff off and complaining it doesn't warm up, idle, or run like it "should" (used to) is worth punching yourself in the face over and over .


True about cams too. Bigger is always better of course! That's usually followed by, why doesn't my engine idle or make any power?

I don't think these motors are comparable, at all. If someone is struggling to compare their needs in an LS vs a BB then they need to go back to the basics. Driving needs and wants should easily dictate which engine is most appropriate.

[CC69Rat]

I understand it's scripted to an extent but, I guess you guys watch Street Outlaws? How many LS motors do you see? How many Big Blocks?

I guess (for me) I just know more about the older stuff. I don't really know how to pull power out of an LS engine as much as I do the SBC / BBC and to me the parts seem pretty expensive. To get a good, low mile LS2 / LS3 dropout is what $3000 or so? I have less than that in my big block (way less) because Pop and I did it ourselves. We didn't have to send the computer off to get it setup, special mounts, special headers, oil pan, etc. I am giving credit where credit is due, the gas mileage is better but if you drive your truck every day I can see where that would matter. If you're just 10-15 miles down the road to the local car show or whatever .. then not so much.

I'm with Ed though. There's just something about the sound of a nasty BBC. I've heard some nasty LS motors too but my point is, it doesn't take me as much money to get to that point with a BBC than it would with the LS swap. It will take me a long time to burn that much gas 10-15 miles at a time.

[jetboat 4]

I have a ls 3 in my Hummer.It's not a good fit the power only comes on with the petal on the floor fun to drive. I've tied pulling a 18' enclosed trailer had to stop at every gas station 3-4 mpg. my opinion is Ls3 may be great in a Camaro or a Vette not in a truck. . I also have a 396 in my 67 rs/ss Camaro burp the petal and the the tires spin, going with a big block in my 66 having torque from the minute you touch the petal. uhuhuh can't wait to get it on the road.

[trac209]

I don't run a big block but I wish I did. I don't drive my truck to whine about every mpg it doesn't get,I have fun with the ones it does lol. There's something that would bug me about dumping an engine in my truck that every stock gm pickup of the day has in it. Idk it just isn't classic. Just like I wouldn't swap the dash in from a new truck either. Same reason I wouldn't put a Japan built engine in a Harley,sure it may be more reliable and go farther in mpg but it's not supposed to be there

[ol_skool_chevy]

My 496 big block will make your butt pucker......the feel of the seat springs pushing into your back is well worth it...full roller cam

[moggey01]

There is a reason for weight breaks for small blocks in heads up classes. It can be hard to get cars that light to take advantage of the break now. Street driven a big block will use more fuel. So it is what is the purpose of the build? At the weight of a street driver truck a big block has to be good for perfomance n/a. The fuel injection stuff and programming helps more with tuning ability with power adders. Does not really make more power, but help keep engines from hurting themselves with individual cylinder tuning and timing. That is the real advantage. It really matters on what matters the most . Cubic inches , gas milage, performance , or cost?

[MARKDTN]

I wasn't going to reply, but I have to get in here that you can make an LS fast and streetable. I have a friend with a '69 Nova with 6.0 LS with twin turbos. 1/8 mile: 5.87 ET, 1.346 60 ft. 119 mph and that was over 2 years ago! He has been into the mid-5s now. All of this has been on 93 octane pump gas with a little octane booster. And he regularly drives it to the dragstrip 100 miles round trip! He does not even own a trailer. His car is not tubbed, it is on stock size rubber (drag radials). It has a TH400 transmission and until a little after this timeslip a 3.70 10 bolt rear out of a '66 station wagon. He finally broke it and now he has a 12-bolt. Virtually all of his competitors bring their cars in on trailers. I would like to hear specs on a big-block that can compete with that and see if they can drive 100 miles round trip to the strip AND compete. I just want people to understand that you can have both power and driveability with modern LS powerplants.

[CC69Rat]

Originally Posted by MARKDTN

.. I just want people to understand that you can have both power and driveability with modern LS powerplants.

Oh, absolutely .. I get it. There are some mean LS motors out there but in all fairness put those same twin turbos on the BBC in the same Nova and he'd have his hands full. LS FTW on the drivability though, no doubt. The BBC just doesn't have the efficiency of the LS but .. the torq goes to the BBC. There are good a bad points to make on both sides.

Nothing but respect for the LS guys here. I just don't know enough about them to build one, or have $3k to drop on an LS2/LS3 build. LQ4 / LQ9 I know.. but still it takes more money out of pocket to build an LS considering total cost involved. Iron block or not. I just had my 396 left over from a Camaro project or I may have gone the LS route.

Hard core drag racing, not daily driven or driven to the track I'm going BBC. Daily driven, running cones or road course racing Id look more into the LS swap. Me personally gas mileage is not a big enough issue to justify the added cost of the swap.

[midniteblues]

I'm not one to put a computer controlled engine in a Flintstone moblie. Kinda defeats the purpose of the simplicity these trucks have.

I guess that why chevy are so awesome for their versatile. They are all badazz no matter what engine is in them.

Rats do look good in a truck bay.

I would put a ls in my camaro though even though it doesn't need it.

[Doug's68SS]

it is off of a mid 90's small block, I picked up a kit that had aluminum adapters to bolt it to a BBC. it uses a later model reverse water pump.

[MARKDTN]

Originally Posted by CC69Rat

Oh, absolutely .. I get it. There are some mean LS motors out there but in all fairness put those same twin turbos on the BBC in the same Nova and he'd have his hands full. LS FTW on the drivability though, no doubt. The BBC just doesn't have the efficiency of the LS but .. the torq goes to the BBC.....

Just to be clear my friend has a 6.0 engine-that is only a 364 cubic inch engine. The smallest BB is 366 and of course nobody runs that because it is a tall deck. Most of your BBs are at least 454 cubic inches if not bigger. And you don't think in the 5s in the 1/8 on stock width tires that he has his hands full? That would be a 9 second 1/4.

A new Z06 Corvette is 650HP and 650 ft-lb torque with a 6.2L (376CID) engine. Don't say that BB is the only way to make torque because it just isn't so. (just as a quick compare modern dyno tests I saw on a 1970 454 LS6 Chevelle has 500 TQ, and a 1969 427 ZL1 has about the same) A 502HO is advertised at 550 TQ and a ZZ502 at 569 TQ. From what I can see actual dyno tests on these show numbers in those ranges, certainly less than 600 TQ for a stocker. It is hard to find dyno tests on a real street driven twin turbo BB. You can find tests with racing engines that have foam filled blocks that make stupid power, but that is not what I am talking about. I would like to see a dyno test on a twin-turbo BB that can drive 50 miles to the track and run in the (mid) 5's in the 1/8 mile and then 50 miles back home.

[toolboxchev]

All points being made here, the simplicity of the old days with torque and hp undoubtedly goes to the Big Blocks.

I like the simplicity of my gen I SBC, yes I can get more power out of an ls setup but the dollars involved with computer crap is a big downer. Why not buy newer truck with all the bells and whistles. My friend owns a newer Duramax and for what it is its still hauls balls when he lays into it.

Trucks are Trucks, working man, blue jeans, t-shirts, red white and blue. Sure its a lot of fun custom modifying a rig with dollars and labor. I love the simplicity of the early years, most stuff can be fixed on the side of the road and believe it or not if your setup is correct it is very durable and not a P.I.T.A.

If I find a good big block the build would be less expensive and I already get about 6-13 mpg so Whine Not! Literally, less rpms is a good thing, mileage wise and wear and tear wise!

The only thing I may really add to a Big Block is a modern transmission with better gearing to help the mileage and step those rears gears appropriately.

[leftybass209]

Originally Posted by MARKDTN

I would like to see a dyno test on a twin-turbo BB that can drive 50 miles to the track and run in the (mid) 5's in the 1/8 mile and then 50 miles back home.

I have yet to prove the legitimacy of "street driven" but I think this speaks for itself. http://www.autoblog.com/2010/09/22/v...les-whips-off/

Also, Hot Rod magazine often has street legal cars pushing upwards of 1000 HP, mostly BB turbo cars.

I'm not for or against LS or BB, I think there's room for both depending on driver requirements, but i'm also not drunk on the LS hype.

Stock, is stock, is stock, but just because Chevrolet dropped a supercharged LS into a 'vette, doesn't make it immediately comparable to an LS6 or ZL1, just because it's "stock". As I said before, there is absolutely no way to accurately compare these motors. We can all agree a BB at the top end of the $$ scale is untouchable by an LS, bigger cubes ALWAYS wins when money is no object. At the OEM scale, they aren't comparable as one is antiquated and the other is OEM with superchargers so neither could be accurately compared.

A good argument should be clear, accurate, relevant, and sufficient. There is no accuracy or relevancy in comparing apples to oranges, hence the popular phrase.

[davepl]

Originally Posted by leftybass209

So many people struggle to understand this. The factory NEVER spent money on something not needed, and they still don't. Why would they waste money on a heat riser if the engine warms up fine (comparably) without it? It costs them $$$$ to install those on every engine that was equipped. Stripping that stuff off and complaining it doesn't warm up, idle, or run like it "should" (used to) is worth punching yourself in the face over and over .

True about cams too. Bigger is always better of course! That's usually followed by, why doesn't my engine idle or make any power?

I don't think these motors are comparable, at all. If someone is struggling to compare their needs in an LS vs a BB then they need to go back to the basics. Driving needs and wants should easily dictate which engine is most appropriate.

It's funny because I watched a tech test-drive mine yesterday - pumped it twice, turned the key, drove away like it was 2015.

But you're right about the last part - letting the needs dictate the engine choice. My point was just that it's not black and white on driveability, or no grandmas would have ever driven a 396 or 427 car to church. Granted they didn't take L88s, but a nice 427/335 or my 396/310 purrs. If not for originality, I'd pick an LS3 every day. But these are old vehicles, and I prefer a well-tuned, driveable period motor. Too many people are putting LS motors in not for the virtues of the LS series, but for the sins of messed up big blocks.

So, "don't compare a good LS3 to a messsed up Mark IV" would be the one-liner.

[kehstr]

Originally Posted by jetboat 4

small blocks are for cars BIG BLOCKS ARE FOR TRUCKS, as simple as that !

Correction, big-blocks are for cars and trucks. Small-blocks are for those that can't handle the power of a big-block

[moggey01]

Originally Posted by MARKDTN

Just to be clear my friend has a 6.0 engine-that is only a 364 cubic inch engine. The smallest BB is 366 and of course nobody runs that because it is a tall deck. Most of your BBs are at least 454 cubic inches if not bigger. And you don't think in the 5s in the 1/8 on stock width tires that he has his hands full? That would be a 9 second 1/4.

A new Z06 Corvette is 650HP and 650 ft-lb torque with a 6.2L (376CID) engine. Don't say that BB is the only way to make torque because it just isn't so. (just as a quick compare modern dyno tests I saw on a 1970 454 LS6 Chevelle has 500 TQ, and a 1969 427 ZL1 has about the same) A 502HO is advertised at 550 TQ and a ZZ502 at 569 TQ. From what I can see actual dyno tests on these show numbers in those ranges, certainly less than 600 TQ for a stocker. It is hard to find dyno tests on a real street driven twin turbo BB. You can find tests with racing engines that have foam filled blocks that make stupid power, but that is not what I am talking about. I would like to see a dyno test on a twin-turbo BB that can drive 50 miles to the track and run in the (mid) 5's in the 1/8 mile and then 50 miles back home.

Hot rod drag week. All the cars are pretty much big block power adder cars. They drive for 1000 miles. They run 5s in the 1/4 mile. Larry Larson has run 5.80s at 250 with a big block twin turbo set up. This is far from what the original poster is asking about. These are race cars and lighter than a truck but they drive more than 50 miles at a time. There are classes for regular guys as well that are not pro street cars. I have never heard of a foam filled block. Most people used a grout or hard block mix. The purpose was to strengthen the bottom of the cylinder. Most new blocks are thicker and no body fills them. This robs power and acts like a heat sink.

[davepl]

Originally Posted by MARKDTN

A new Z06 Corvette is 650HP and 650 ft-lb torque with a 6.2L (376CID) engine. Don't say that BB is the only way to make torque because it just isn't so.

I'm fortunate enough to have one of those, and you also have to remember NET vs GROSS vs current SAE ratings. I also have a 427/390 car.

I bet that 390 is more like 300 net. So the Z06 is LITERALLY like having two 427s under the hood.... not quite for torque, but certainly for horsepower.

These ARE the good old days, at least for power, safety, reliability, and pretty much everything else besides working on it yourself! And if you have a manual, that's not all that bad either.

[summitflier]

It depends on what you're looking for.

Yeah there are 1,000 hp+ big blocks out there.
How many of them are street legal? How many run on pump gas?
How many of them get 18mpg? How many of them do it quietly and efficiently?

The LS is a driver's engine.
The old big block doesn't have variable valve timing.
You can put throttle body injection on a big block... but none came from the factory
that way.
The LS makes 450HP +.
It does it quietly and efficiently. It does it on pump gas.
It does it while getting reasonable gas mileage.

You want to burn the rubber off your back tires? Get a big block.
You want to drive cross country without spending a fortune? Get a LS.

Also keep in mind, the old 70's factory 402's were only rated at 310HP.
The last GMC 454's put in trucks from the factory were only rated at 255HP.
(7.4L EFI)

[kehstr]

You have to remember that a bigblock will normally put out more torque than an LS, so it just depends on the real use of the truck

[1972RedNeck]

Originally Posted by MARKDTN

A new Z06 Corvette is 650HP and 650 ft-lb torque with a 6.2L (376CID) engine. Don't say that BB is the only way to make torque because it just isn't so. (just as a quick compare modern dyno tests I saw on a 1970 454 LS6 Chevelle has 500 TQ, and a 1969 427 ZL1 has about the same) A 502HO is advertised at 550 TQ and a ZZ502 at 569 TQ. From what I can see actual dyno tests on these show numbers in those ranges, certainly less than 600 TQ for a stocker. It is hard to find dyno tests on a real street driven twin turbo BB. You can find tests with racing engines that have foam filled blocks that make stupid power, but that is not what I am talking about. I would like to see a dyno test on a twin-turbo BB that can drive 50 miles to the track and run in the (mid) 5's in the 1/8 mile and then 50 miles back home.

It may make the torque, but at what RPM?

[sneakyfast]

I didn't notice anyone talk about turbo lag. As I understand it most of the LS engines can only get to BB power by adding a turbo (or two). I don't know if technology has changed but every turbo engine car deals with significant turbo lag. That is going stop light to stop light the engine has to spool up to a certain RPM to get the turbo going and make power.

This is why I like BB better because 90% of my driving is stop light to stop light. You mash the pedal and the truck goes...no waiting and a lot more fun in 90% of street driving condition.

[Eddie H.]

Since I'm too cheap (frugal) to spend the money on a BB or LS swap, I'm happy with my SB 406. It's simple, reliable, and a pretty good compromise between BB torque and SB fuel economy.

[Alex V.]

Originally Posted by 1972RedNeck

It may make the torque, but at what RPM?

The new Corvette engine has a torque curve like a railroad tie - IIRC it passes 600 lb. ft. By 2,500 RPM and peaks at 3,600. It's a forced-induction, direct-injection piece of machinery with fully variable valve and ignition timing. If a 454 cubic inch engine had all that tech scaled up and bolted onto it, it might not be legal and certainly not EPA compliant. The 1.4L turbo (that's 83 cubes putting out 138 HP and 148 lb.-ft.) in my Cruze is a legitimately impressive powerplant - and that's just what GM put in their economy cars - but the fuel will continue to be supplied to my 350 and 454 by a mechanical fuel pump and four barrels, ignited by copper spark plugs via a distributor cap, the way it was designed to, the way I've seen those engines do it since I rode behind them in a car seat. Because those engines speak a clearer, more authentic language than the coil-on-plug, MPFI, aluminum-headed powerplants of today, and because I have complete confidence that if it quits, it'll either be my fault or the a legitimate failure of hard parts.