The stock LS heads (the newer the better) outflow stock BBC heads by a wide margin! Fuel injection. Computer controlled. Roller cams. Need I go on?

There's even more to it than that with valve train angles, hollow valve stem, and other stuff beyond my novice level of engines, but the newer stuff can easily outpower the older stuff in stock form vs. stock form. :yes:

 

add to that

1. INDIVIDUAL COIL PER CYLINDER. coil fires once per cycle instead of 8 times a cycle

2. sequential fuel for superior gas mileage

3. if you get an alum ls1 it is close to 200lbs lighter than a bbc. and thats weight off the front of the car

4. o ringed intake and oil pan gaskets make it a joy to work on

5. pulling cam in dead easy

6. changing springs is dead easy, also no need to do the whole io/ec or whatever it is song and dance to reset the rockers.

7. hydraulic roller from the factory

8. 15 degree heads from the factory. i wonder what 15 degree sbc or bbc heads cost

9. l92 heads that are $700 complete for the pair that outflow most bbc heads

10. 6 bolts mains stock

11. stock crank that has held 1300hp without a hiccup

13. no water through the intake makes it easier to pull

14. acc. drive belt has a tensioner from the factory

15. internally balanced from the factory

17. equal spaced intake and exhaust ports offer superior flow

18. cam sync allows for cylinder to cylinder tuning of fuel and spark

19. iron block supports up to 1500hp

20. will add more as i think of it.


oh, and they make power. my 293 cid cam only engine with only 1( thats ONE) psi boost, ran 7.8 at 98mph in a 3200lb combo

 

take one apart and you will see what makes them tick.. everything about them has the look and feel of high end race parts for old school small blocks.
how much is a set of 18 degree heads for a small block? i think the worst LS heads have 15 degree valve angles and the best have 12 degree valves, which opens up the port layout so there are no bottlenecks. the "bad" LS heads are better than all but the "best" old school small block heads.
6 bolt main caps with 4 bolts in the regular up and down configuration with 2 bolts that come in from the side..
head bolts that tie into the block down by the crankshaft...
the oil pan is a structural part of the block..
the cam is placed up high in the block compared to a regular small block, which allows shorter (and thus lighter) pushrods that go up to the valves at a better angle.
roller fulcrums on the shaft mounted rocker arms..
ventilation windows that let the air in the crankcase move around in the block, which causes less pumping losses as each piston moves up and down.
the oil pump is driven directly off the front of the crankshaft, and there is no distributor to put extra strain on the full roller timing chain.
roller lifters riding on a cam with a larger base circle.

 

See, told you others would know more than I , but the basics are that the LS engines are MUCH improved in so many ways. :hurray:

 

Lets not leave out the simplicity factor. Any monkey with a few spare thousand can make a reliable, extremely efficiant and dependable 500rwhp ride.

In my eyes, no power adders included. SBC's just cannot compete, with out some sort of sway.. As in SB2.2 heads which kind of negates comparing SBC to LS.. As more of comparing a bastardized cup motor to an LS engine.

* Whats it cost to get into a set of those sb2.2 heads, with accompanying intake? Not to mention rockers, custom cam pushrods and springs*

 

Rich,
I too felt the same way you do In this post. I grew up with the BBC being the bad boy around town. I remember as a teen thinking that someday I would have a BBC. Looking back now at 50+ years old having built many BBc's and SBC's for myself friends and others it has been a joy tuning these projects for max power performance and reliability.
I can remember taking a 383 to the chassis dyno to tune before a track outing, it put down 360ish at the wheels thru an auto and 12 bolt. A local tuner was there with a late model LS1 Camaro. With a cam and bolt on pieces it laid down 406RWHP! My thoughts were how could that be?? This car Idled like stock but just roared at WOT. I got to know the tuner and would attend some of his tuning sessions and the power from these engines was just amazing.
Keep in mind there is not a smoking gun where you say AHA! that is why they make power.
It is a combination of things that add up to power.
Things I discovered on my first performance build of a 6.0 truck engine,
The short block takes practically no effort to spin over, you can turn the assembled shortblock by hand, just grab the crank snout and spin!
The ring package is lighweight low drag(1.2mm compression and 3.0mm oil rings.)
The pistons are above the deck about .008", remember building older engines for zero deck?
with a .050 factory gasket these engines are running .042 quench, stock!
raised 55mm cam core offers several advantges for valve train stability, shorter pushrods, lightweight 8mm valves with beehive springs. With a spring swap you can turn the stock HR setup to 7k with no float.
The cylinder heads are mirror port configuration like SB2. Stock L92 heads are 260cc port with a 2.165 valve(sounds like a BBC head) they flow 300cfm untouched!
The bottom end is very stout with 6 bolt mains in a deep skirt block, turbo guys are making 1000 hp with stock bottom ends.
These engines are a joy to work on with the modern sealing, gaskets can be reused, no blue goo required.
The best part of all this is that 6.0 truck engines are plentiful and cheap!
I live in the northeast, a local recycler has 7 6.0's for sale at (1200) apiece.
Take one of these and put a cam/spring swap , carb and intake, MSD controller and you have a 500hp pump gas street engine... these are good times for those that embrace the LS platform.

 

A tale of 2 small blocks..
engine #1
gen 1 383.
late model HR block
10.5/1 compression
AFR 195 Eliminator heads
Super Victor manifold
Comp 294HR cam
Idle video,

This combination would run typically 10.30's at 128-129mph

 

The gen 1 383 at the track...

 

I still fault GM for being run by a bunch of lawyers and accountants ( and shorted its stock soon after re-issue to prove it!) , HOWEVER they must still have good engineers in the mix as the LS-series is a very, very well engineered line of mills.

Simple, 21st century vs 20th century. Those "cathedral" ports must have been fun to model.

 

Engine #2
6.0 Iron LS
Untouched L92 square port heads
Stock shortblock
239/247 HR cam
9.8/1 compression
Single plane GM manifold
The engine before it was installed in the '57 Corvette

Dave

 

Video of the Corvette with the 6.0,
Same track, approx +1000 ft DA from the video of the 383 pass

The car has gone in the high nines with the 6.0 in good air.
The 6.0 is down almost a point of compression and 20 cubic inches from the Gen 1 383.
It is a solid 3 tenths and 4mph quicker.
Make your own conclusions...

Dave

 

It's all about techological advancements.......time marches on and everything eventually moves into the past. As will the old SBC and BBC. In the mean time I'm gonna enjoy my 'ol school 496 (lol).

 

There is no magic in LS engines. If you incorporate the same advancements in 'ole schools SBC/BBC's you end up with similar type improvements.

The LS engines just start with all that stuff stock and are therefore easier and cheaper to build until you get to a certain power level.

Try to make ~900+ HP naturally aspirated with an LS and tell me they aren't just as expensive as a similarly built SBC/BBC.

Nowadays there are conventional headed SBC's and BBC's making 800+ HP and 1200+ HP respectively. The game has changed for everyone.

Knowledge is power, not magic.

 

Jason is dead on here!
When you get to the higher HP NA builds the playing field levels out with respect to the cost of the parts.
The LS shines for the street guy looking to build a cheap reliable 500hp engine using stock parts.
Just finished a 900+hp 454LS for a friend. The cost of this small block is not cheap,
LSX block
all forged American made internals
Sheetmetal intake, All Pro 12 degree heads..
I don't think this one is ugly,

Dave

 

Interesting read!I dont know anything about these engines,I dont assume they would bolt up to say a th400 or a stock bellhousing muncie 4 speed?How many different versions are there?

 

A Conventional TH350/400 will bolt up to a LS series of engines no problem, only thing is ONE bellhousing bolt does not line up. No biggie, no issues on my end. You can either buy a spacer to accomadate the extra room that the torque converter will see.. or you can buy a flexplate already setup for everything. *see Below*
http://www.speedwaymotors.com/LS1-E...s.com/LS1-Engine-to-GM-Auto-Transmission-Adapter,8701.html?parentDisplayId=5070

And if your going with a 4 speed. The popular 621 aluminum bellhousing works on the back of the LS engines FLAWLESS. EVen allows the use of a SBC 11 inch clutch and pressure plate. The flywheel will have to be of LS Variety, but luckily. Most manufacturers are making them with both bolt patterns, and are of a 168t flywheel. Heres a good read if your interested in using your 4 speed, ive had good luck following another post that mimics this.

http://ls1tech.com/forums/conversio...ions-hybrids/1472584-mating-sbc-bbc-trans-t10-muncie-richmond-tko-ls-motor.html

Even with the M20 trans and 3.73 gears. My vehicle still knocks down 21-23mpgs on the highway.

 

Symmetrical ports instead of good port/bad port like all the old stuff. It takes either old school (read: abandoned) symmetrical port heads or spread port (Big Duke/Big Chief) to get to this starting point.
A few years back, Brodix's BB2Xtra was the cat's a$$ because it flowed over 400cfm. LS heads are getting that now with much smaller ports and cylinder bores.
A stock 6.0L iron block will take about twice what an old smallblock would and a good bit more than a big block.

They're great platforms, but they do have their limitations. 502 cubes is the biggest I've heard of and it takes a sheetmetal intake to run it. Bore size is limited which also limits valve placement and size.

The GM engineers absolutely did their homework on this engine. Ford's mod motor is OK, a lot more complicated and makes less power. And Dodge's "hemi" is pretty much a joke in comparison - old school technology with some better heads.

 

Outstanding performance and…………………they look really cool.

 

I remember back when the SBC came out in the mid 50s, a bunch of flathead guys were posting this exact same thread on model-a.com

 

^ Personally, I can't stand the look of 'em in stock form. Plastic covers, spaghetti wiring, can't really identify any of the parts or components, pretty much every new generation EFI engine looks the same under the hood, IMHO.
...until you drop a single plane intake and carb, relocate the coil packs and add a good looking set of valve covers. Then they really SHINE!

 

I agree 100%, but I have an LS3 crate motor in the Chevelle I am building now. And I do not care how much power it makes I will not pull the 548 from my red Chevelle.

 

Yup- tough block design, 15-degree heads, identical ports that are spread out so there are no 'hot spots' - that's the kind of stuff that makes power. Great design and one that'll still be viable way into the future.

I'll go there eventually. It's inevitable. I'm already planning it in my head. It'll be over 450 ci, be pump-gas compatible, make around 700 hp and deliver more than 20 mpg.

Those kinds of numbers sound impossible, but it's already being done. They're amazing engines and I'm glad GM stuck with pushrods and made them. The aftermarket has really embraced them and there's more cool stuff coming out for them all the time.

 

I am debating "updating" my 454, and have been considering a 502, but I am also considering a 6.0 possibly. I assume they make flex plates to use a TH350 or 400 with a conventional converter? Also, how are these engines compared to a BBC as far as torque on street driving. I understand they make big power, but I don't want to be having the engine screaming around town to keep it in a torque power range. My car is a 71 Monte, so it is relatively heavy as well--definitely not the like the vette in the previous posts! One last question: If I found a 6.0 for $1000 or so, how much else would I need to actually get the conversion done assuming I switched it to carbureted and changed out the cam?

Honestly, the LS just sounds too good to be true, I feel like there has to be some drawbacks that I don't know about.

 

One last question: If I found a 6.0 for $1000 or so, how much else would I need to actually get the conversion done assuming I switched it to carbureted and changed out the cam?

Honestly, the LS just sounds too good to be true, I feel like there has to be some drawbacks that I don't know about.

For the conversion, you typically need to change the oil pan, mounts and headers...

I haven't looked really close, but the oil pans and swap headers used to be pretty expensive (compared to regular SB/BB headers)...

Some other issues, depending on what you want (accessory drives, A/C, etc)...

 

Dyno video of the 454LSX.
This is thru a 6000 stall converter and th400/12bolt..

Dave

 

Dave,

Have you guys got that bad boy down the track yet?

 

W
I rode to the track with the owner.
His belts were out of date and he didn't know it!!
!st shot ..blew the tires off...
Second attempt he put out both bulbs!! no time
We are scheduled to run it at the NA shootout on the 29th.

Dave

 

Yeah. But why spend all that money to build that when he could have had more power by using less compression and a turbo?

 

Yeah. But why spend all that money to build that when he could have had more power by using less compression and a turbo?

Cuz he could

 

With all the crying about fifteen degree valve angles, I begin to wonder why you aren't running Oldsmobiles.

They have a seven- or eight-degree valve angle. Must make twice the horsepower of an LS engine...











Valve angle, by itself, doesn't mean squat.

 

Valve angle, by itself, doesn't mean squat.

Alone, perhaps not, but a good valve angle sure can help if other things line up and take advantage of a good valve angle.

I don't know for sure, but are there any Oldsmobile heads that can flow like an LS head?

 

someone asked about hooking an LS up to an old school bellhousing and manual trans- it can be done with nothing but a flywheel for a 6.0 in a 99-3ish 3/4 ton truck and a pilot bushing for (i think) a 98-02 LS1 6 speed F body.. the Flywheel is available anywhere for about $65 and the pilot bushing was a $30 GM part as of a few months ago.. you just bolt up an 11" clutch for whatever trans you are running and use your existing clutch linkage parts and clutch fork.

this is how i'm gonna eventually put either a 5.3 or 6.0 in my 87 GMC 3/4 ton truck.

 

For the guys in the know, to get a 6.0 to duplicate say a 496/502 at either the 500hp and say 600hp levels, what would need to be done to a 6.0? 500 and 600hp is representative of the kind of power these MILD BBC's are making today.

And once the 6.0 acheives this sort of power, is it radical, and is the MPG same/better/worse as the BBC?

 

from what ive read and my calculations, 500 HONEST hp is a cam and spring change, and thats more than what many mild bbcs make .

also noteworthy is that a 500hp lq4 is going to be faster than a 500hp bbc at the track because you are losing about 150lbs going from bbc to lq4, right off the nose, which also gives a better rear to front weight ratio.