this whole talk of bbc and ls i say ls hands down. but hey if yall really want to race ill race in my sisters pink tricycle that will put up a fight against that 8 second car lol i kid i kid
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this whole talk of bbc and ls i say ls hands down. but hey if yall really want to race ill race in my sisters pink tricycle that will put up a fight against that 8 second car lol i kid i kid
Yeah, pretty much is the same engine, only cast in aluminum and w-out water jackets. of course so many mods are done.. but the overall design is all mopar... no other auto engine on the planet can match the hemi for all out boosted power.Quote:
Originally Posted by PurpleMinivan
back down to pro stock level and the ports of the BBC are where the power is, ports on the hemi are too big.
Quote:
Originally Posted by Mang213
I've never owned a Big block Chevy, but have 2 ls based vehicles... know people who have bbc autos..
I can tell you the LS is somewhat an engine from heaven.. WE got into this debate a few days back with the I-force 5.7 Tundra engine vs the ls engine...
Even with v 4 valves per cylinder racing heads that probably cost $12,000 pair, the Tundra's engine could never hang with a Ls6 stock for stock, or esp with mods... the ls6 would be 100-200 more hp with 4 valve heads... it is just an incredible engine ...
For the street I'd much rather have a 11 sec 30 mpg ls powered z28 than a rat powered 10 sec 69 camaro that gets 7 mpg..
But to say a LSX vs BBC same cube and the LS would make more power is crazy.. the Big Block chevy also has been keeping up with modern technology..
a 427 BBC vs a 427 lsx, a 454 bbc vs a 454 lsx, a 500 bbc vs a 500 lsx..
The Big block chevy will prevail.. sure it had to spin a distributor etc, but the heads on the BBC are big and flow like no Ls can dream off..
Just one example
go to the AFR web page.. look up LS heads, then look up there Big block Chevy heads..
those tiny AFR heads (I'd love to have a pair don't get me wrong) are nothing to the GIGANTIC BBC heads...
Some of those Big block chevy heads have 2.19 intake valves.. and some have huge pop can sized 2.25 2.30in intake valces... flow 360 cfm just playing around...
sure a LS7 vell will destroy a 90 SS 454 truck or a ls6 1970 Chevelle.. stock..
but when you put the same $$ into them... I'd no bed agaist the BBC if it is built right...
After looking at vig again, looks like the Nova may be a older small Block chevy, it is dark though, still proves old school engines can make power, magnify this for a RAT moter.
Here are two guys, who supposed to had a argument over the net or something, bad mouthing.. one is a 02 Vette with a (not stock engine of course) built LS7 (SPRAYED).. the other is a old school 72 Nova (SPRAYED) .. with a RAT motor in it..
Both cars ran great.. both are 9 sec cars I believe
a $1250 bet, both trailer to race site on some old road somewhere..
YouTube - $1250 Race - '72 Nova vs '02 427 ci Z06
Good running and sprayed LS7 2002 Vette, but he lost $1250 cause he thought the LS was superior and found out that you don't mess with a good running BIG BLOCK CHEVY..
Ls engine are great, but those pop can vales, mop bucket pistons and high flowing aftermarket heads are nothing to take lightly.
The Fastest street cars on earth... 2000-2500 hp.. are not 1500 hp 6 cyl turbo imports, are not hemi's, are not LsX's either... they are Boosted Big Block Chevy's!
Best thread Ive read in a long time. Personally I love them both, each has advantages and disadvantages just depends on what you're trying to do. All out racing, BBC for the win.
Now, what do you say we get back to LS only topics. Maybe damnyankee can help us out here with some new pics of his Titan
I love the LSx. And I believe it is the future of hot rodding.
But there's nothing quite like a bad boy big block Chevy.
The car in this vid is kind of ugly, but the big block in it makes up for it. Unbelievable power on the street!
YouTube - NRE 522 Big Block Twin-Turbo '63 Pontiac Tempest
And for those praising the new LS7, you must remember the first LS-7, the now 40 year old 500hp flat tappet 454 LS-7 big block crate engine.
Of course if you are looking for something a little more up to date than the 40 year old LS-7... you would be looking at the highest horsepower passenger car engine currently offered by GM, the ZZ572 big block. Under rated at 720hp, but actually makes around 800hp right out of the box. Add nitrous and you would have over 1,000hp the easy way. This engine would eat ZR1 Corvettes for lunch and it's available at your nearest GM parts department.
http://www.gmperformanceparts.com/_r...GB_DELX_03.jpg
Ok guys, ran some desktop dyno numbers on a stock LS7 small block vs. a 454 H.O. big block. I used merlin ported heads on the big block, because we all know it's not fair to compare stock LS7 heads to the stock 454 H.O. heads.
STOCK LS7 SMALL BLOCK
RPM -- HP -- TQ
2000 - 208 - 547
2500 - 272 - 570
3000 - 334 - 585
3500 - 394 - 592
4000 - 438 - 575
4500 - 473 - 552
5000 - 493 - 517
5500 - 491 - 469
6000 - 468 - 409
6500 - 444 - 359
7000 - 403 - 302
STOCK 454 H.O. BIG BLOCK w/ merlin heads
RPM -- HP -- TQ
2000 - 198 - 520
2500 - 255 - 536
3000 - 310 - 542
3500 - 360 - 539
4000 - 397 - 522
4500 - 416 - 485
5000 - 414 - 435
5500 - 394 - 376
6000 - 361 - 316
6500 - 336 - 272
7000 - 284 - 213
Now some of you may not agree with these numbers, but I used the same method of construction for both engines. The LS7 is an 11:1 engine, while the 454 is a 8.75:1 engine. Also, the LS7 heads flow more than the 454 heads. This was just for a comparison between a STOCK LS7, and a STOCK 454 H.O. Infact, I helped out the big block with ported heads, and it still came up short.
My point about comparing both engines with the same bore and stroke is that is the only way you can match a bbc with an LSX, when trying to determine which engine is more effective at what it does, all things being equal. The LS is much more efficient and makes more use of its available power. Of course you can take a bbc and bore/stroke it out for more cubes to gain an advantage, but we were talking about motors of 454 ci, not a 502, a 572, or whatever else you want to throw against the wall. A 454 LSX with the same bore/stroke as a 454 bbc, the same compression, with heads that flow equal amounts of air, and with the same profile camshaft, will almost certainly make more power. I dont really see how anyone can deny this, as long as we are staying on topic with the OP. Put it this way, if GM developed a big block Chevy that was designed after the LS architecture (not an LSX block, but a true big block with a raised deck, 6 bolt mains, cam higher in the block, and larger bore centerline), it would blow the existing bbc out of the water.
im out of breath now, but great topic
So you compared a high compression motor to a low compression motor and the high compression motor won. Nice job. What a waste of bandwidth.Quote:
Originally Posted by truckinL33
Not only that but you made the 454 HO produce less than the GM hp rating, which is probably under rated by GM.
The 40 year old LS-7 454 big block matched the output of the new LSx LS7. The 43 year old L-88 427 big block also matched the output of the new LS7. The L-88 was very under rated, but it regularly pumped out 500+ horsepower on the dyno way back in the 1960s.
Some of you need to learn a bit about the history of Chevrolet.
Get real. The LS7 is the second highest horsepower LSx motor currently produced by GM. Compare it to the second highest horsepower big block produced by GM. The 620 horsepower 572, which actually produces around 700hp. It would eat the LSx LS7 alive.
O yea, I forgot. It's the internet, EVERYONE IS IGNORANT.
it was a stock for stock comparison but wanna be XLR8N can't read
The 454 HO never came stock in a car. But the L-88 427 big block did 43 years ago.Quote:
Originally Posted by TATERNATOR
Quote:
Originally Posted by truckinL33
Yeah, that's a low compression big block smog motor,
Ls7 heads flow more than crap BBC heads ,but not more than good aftermarket BBC heads. Merlin makes some heads that flow 400 cfm and more.... would not be good on a 8:1 454 though.
I love LS motors just like you guys, but they are not king of V8's..
I can tell you that not only will good Big Block Chevy's rock a good LSX engine, but also Big Block mopars with the right heads..
many 440 RB engines with 500 cubes and Indy 440-1 heads can get 800-1000 HP EASY without spray or boost.
look at NHRA pro stock engines, they can use ANY production V8 up to 500 cubes IHRA is 700 cubes I think.. they can use a LSX if they wanted, nope.. use old iron BB Ford, Chevy and Dodge engines.. Hemi's I think have to run 1/2 lb per cube more weight on car..
I know there are aftermarket LS style engines that can get over 500 cubes,,,,
But keep in mind there are aftermarket Big Block Chevy engines that can get 800-900 cubes,, Arias even makes hemi heads for BBC..500 cfm plus flow...
So when ever you pull up next to a Chevy car with a Big Block in it... better not bet a bunch of money on that LS.. cause if the Rat is built right, your going to see some old school car tail lights.
This is a fun thread...
maybe if those old Big Blocks of 40 years ago was never invented, then the LS engines would be supreme.
I know but it was the motor he chose though
And he chose the wrong motor.Quote:
Originally Posted by TATERNATOR
O and I love the sound of a BBC done right
The LS6...ZL1....427.... the 500hp LS7, and more, are all revisits of legendary big blocks of the past.
The Z06 is also a revisit of the legendary Z06 Corvette of the early 60s.
Wow, you are a freakin idiot. the horspower rating changed in the early 70's. Not to mention that the dynos back then were rigged to show higher power. do some research on the dyno and you will find exactly what i typed.Quote:
Originally Posted by IXLR8
Why do the BBC guys find it necessary to challenge a SMALL BLOCK 427 with a 572? that is the most ignorant thing posted in this thread. Why did GM COMPLETELY phase out the BBC from its vehicle line? i think it had something to do with the fact that there are better ways of making power than just all out big cubes. Oh, and the hippies didnt help either :argg: I am one of the biggest fans of the L88 and ZL1 but the L88 has been replaced by the LS7. Nothing would make me happier than slapping an LS7 in a stingray and whoopin on some big block ass :lol:
Case in point: Pound for pound, dollar for dollar, mod for mod, cube for cube, the LS will always outperform the BBC's.(by outperform i mean do it all, daily drive, mpg, make power, reliability, etc.)
I would agree on this...a 5 inch bore spacing lsX big block engine would be scary...4.5 inch crank.Quote:
Originally Posted by Mang213
Still the Big Block Chevy as it stands now is king, lots of modern tech can be added to them... even Crank triggers for Computer injection and timing.. although that gets expensive.
Good thing for us LS owner car guys, that they are rare to be seen now. and most or old worn or smog engines.
I didn't start to study LS1 engines till around 2008... I assumed in 1997 when the Ls1 came out in the Vette, and again in 1998 in the Camaro that this new engine would never be like the Lt1 or old school SBC..
90% of the time new is not always better, but GM did good on the LS1...
The EPA forced the phase out of the big block. There was no such thing as a high performance V-8 after the early 70s. As the car manufacturers got better at emissions and mileage the motors started to make better power. Then they started to get bigger again. That's why you now have a 427 again.
But it was too late for the big block. You can still get them at the parts department, you just can't get a good one in a car anymore.
If GM spent the money on the big blocks they would match everything the LSx does better than you might think.
The big block naturally has more cubes than a small block. That's why it's a big block. To utilize the advantage of a big block, it's going to have a lot of cubes. If you want to compare a small block to a big block you are going to have to live with the fact that the big block is going to be bigger. Get over it.
Why are some of you so immature that you can't type a post without insults?
Again, the internet. Everyone is ignorant, except for you I guess.Quote:
Originally Posted by IXLR8
i understand this already. i just think its funny that a 427 LS7 small block generates an equal amount of power as the L88 with 4 times the mpg.Quote:
Originally Posted by IXLR8
this means they were phased out for their inefficiencyQuote:
Originally Posted by IXLR8
so if GM made a big block LSX, it would be wicked awesome? i agree 100%Quote:
Originally Posted by IXLR8
if it makes you feel better about yourself that you need to resort to the 572 in comparison with a SMALL BLOCK 427 then thats fine with me.Quote:
Originally Posted by IXLR8
i have over 1300 posts without insults to members. the fact you take the 60's dyno numbers as 'solid' is what was getting me. every auto manufacturer had their own dyno with formulas to make the hp rating higher. i think in the 80's or something everyone started to the use the same formulas to reach the max rating they can get.Quote:
Originally Posted by IXLR8
The 427 LSx doesn't get 4 times the mileage. If the old L-88 or ZL-1 had EFI and roller cams they would make more power and get much better mileage than they did.Quote:
Originally Posted by cjriojas
The big block was phased out because it was too big. Everything got small for a while. The V-8 came very close to being a thing of the past.
The LSx isn't a big block for the reasons mentioned above.
So you think it's OK to compare the biggest small block to the smallest big block? I don't think so, big blocks got bigger over the years, not smaller.
The formula to compute horsepower has never changed.
The configuration of the motor when dynoed did change with GM. But it had nothing to do with privately owned dynos which regularly showed the L-88 producing 500+ horsepower back in the 60s.
FWIW, the correct factor for calculated HP has changed many times and there currently are quite a few correction factors being used at this time.
The way the factory measures horsepower has changed. But the formula to find horsepower has never changed. The correction factor only has to do with the weather and altitude.Quote:
Originally Posted by RedHeartbeat
not just weather and altitude but I'm sure know that.
The correction factor only takes into account the weather and altitude and attempts to create a level playing field to compare dyno numbers.Quote:
Originally Posted by RedHeartbeat
I think what some of you are struggling with is when GM changed from gross horsepower to net horsepower. I believe what changed was net horsepower had the engines accessories in place. They have probably also changed the correction factor they use over the years which is why some of the GM engines seem under rated.
Back in the 60s they played major horsepower games for other reasons. Some of the ratings were purposely way off the mark.
How about a big blok 427 vs an LSx 427? Do I really need to say it again? Or like Boz said are you that ignorant?Quote:
Originally Posted by IXLR8
CUBE FOR CUBE THE LSX WILL OWN
You need to go back and do some reading.Quote:
Originally Posted by bangbangskeetskeet
What exactly do I need to re-read all knowing master of the interwebz?Quote:
Originally Posted by IXLR8
the formula for horsepower did change. it changed at least once. however, the engineers and programmers used a variety of correction formulas in their implementation in the dynomometer to achieve the best numbers.
Horsepower is a product of torque and rpm.
The formula a dyno uses to find horsepower has not changed.
This is the formula. This has always been the formula.
HP = TQ x RPM / 5252
:slice: How did I miss this! :popcorn:
we need a a daycare section or something lol
That's absolutelty histarical! :LOL:Quote:
Originally Posted by TATERNATOR
So is your spelling. :lol:Quote:
Originally Posted by truckinL33
really guys 16 pages......
STFU!!!!!!!!:thanks:
Hot rod tested all these out on the same car, same track, close to same time and weather... so it's gotta be true. And the BBC spanked them all by bus lengths!!!
We Thrash on Eight Crate Engines From GM Performance Parts - Hot Rod Magazine
Close this thread... I can go cry now in the corner... proof is in the article lol remember these are all crate engines...
That was a good read, thanks for that.:hyper2:Quote:
Originally Posted by PurpleMinivan