nmp27

iTrader: (2)

On the 8th day he said: Let there be Forced Induction

Quickin

An LSx engine will never be able to produce the power of a BBC with the same reliability and DRIVABILITY. Cube-for-cube....OR....all-out max builds for each. NEVER. They will never move anywhere near the air as a BBC, SO SIMPLE.


Nobody here has ever mentioned stock-for-stock...OR...stock AT ALL.

If can put this in his '70 Chevelle for basically the same price when all is said and done and *** rape the LS7 if he installed that. Upgrade the heads on the 572 and he'll have a reliable engine that will make more power than any LS7 ever has or ever will...AND STILL BE A DAILY DRIVER with RELIABILITY. The LS7 will be on the verge of exploding at any time if built to the hilt.

http://www.crateenginedepot.com/stor...6YNIRmCaeC6fIs

$15,000+ when all is said and done from what I've seen on this forum. And then you're sitting with stock hp, 450 RWHP What fun is that. In a big heavy Chevelle, it'll be a dog. He would have to give it to a builder, along with $10,000 to make it what he needs.


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KHShapiro

iTrader: (10)

that was post # 56
You started comparing

Looks like its carb to me so add for the ECM Injectors and manifold. what does that bring it to now??? how much more than an LS7 and whats the weight difference?

try talking about the obvious , head design, weight , piston angle. pros and cons. whats the hp rating per hundred pounds.


While no doubt BBC's have more potential to make more power due to larger cubes. there is no reason why you cant build an LS for around ( everyone has there own around figure) the same price as a BBC, for what it is that you are looking to do . you have your mind set on a BBC thats great there is nothing wrong with that and i dont think anyone in there right minds would tell you other wise. But dont think for a second that LS motors arent capible of big numbers too, apples to apples (CI) the LS series is a better design.

Stang's Bane

iTrader: (22)

Or he could just give a builder $15K and have over 600 rwhp NA and another 200 with a bottle.

You can build 1000 fwhp with a ls motor reliably for under 20K.

Stang's Bane

iTrader: (22)

Hve you priced a AL BBC??? Not cheap.

A BBC block will be heavier than a comparable CI ls block, it has to because it is physically a larger engine.

KHShapiro

iTrader: (10)

oh and C6 zo6's stock, on stock tires have broken into the 10's.
There one in my garage thats 11.17 , with 1.8060ft , stock.
Yes its a ligher car, a much lighter car.
a nice shot of NOS or some psi in a Chevelle , will be a low 10 maybe 9sec ride witht he right chassis set-up.

Quickin

But that's true. A BBC 427 will kill an LSx 427. There's not a head made on the planet that can feed 427 cubic inches for an LSx engine. But a BBC 427 has heads available to OUT-feed 427 cubic inches. That means much more power. And being a BBC it will be MUCH stronger and last MUCH longer.

Is this not a fact.

I never compared stock engine. Stock engines are useless to everyone here.


He's gonna drive it 5,000 miles a year, I think if it reaches his goals, he won't care about carb or EFI.

I am.
Hundreds of pounds...Its a '70 Chevelle. The original iron block that was in there can't be much different than an aluminum BBC block today.
Heads, BBC heads KILL any LSx head.
Piston angle...what does that have to do with anything????


.

Quickin

How about under $13,000 plus a 200 shot. And have much more reliability than a maxed out pump gas 600 RWHP LSx.
http://www.crateenginedepot.com/stor...6YNIRmCaeC6fIs

I don't know man, over the past year or so, I've seen nothing but explosions and failures with all the TT LSx's and SC'ed big horsepower LSx's. No need to name members with these failed LSx big power engines. And all were less than 1,000 FWHP.


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ss dave

On weight, I replaced my iron SBC 383 with a LS7 and had to cut the springs to lower the car to the right height due to decreased weight, about 150# less than a SB.

Stang's Bane

iTrader: (22)

The link is dead. Are you talking about the 720R/572? If you are that engine requires race gas. And the weight on that thing is killer..


Like I said, a BBC has a higher power potential than a ls motor. CI rule. That cannot be denied. All else being equal though, I will take a small block over a big block. When I said all else, I mean a comparable set of heads, compression, and intake. It will make the same if not more power and the weight difference makes even more of a difference. If you are looking at a 200 lb weight diffenrence, then you would need to make at least 50-75 more hp to run equal times. That is not even taking into account the location of the weight, which is in the worst possible place, over the front tires.

KHShapiro

iTrader: (10)

Hmmmm that so…… Tell that to ETP, AFR, DART.Damnit , I should chuck mine away..

why is this?

You maded a statement about 427 bbc vs. a 427 ls which if im not mistaken they make a LS7 . But i guess i have to take the blame here on that because i assumed you where refering to the LS7
I pretty sure with equal amounts of money I could build a LSX 427 that would out perform the BBC 427 with , again equal amounts of money thrown at it, beyond stock versions



Whats it gonna be EFI or Carb are we allowed to adjust the prices now or is that just for the BBC?



Hundreds of pounds , BBC weights way more than an LS series
I dont know what the difference is between the Iron BBC and the Aluminum BBC block is but whats the price difference? how much more money does that add up to on your BBC build, and its still heavier than an LS
Heads are totally different, again I think ETP , AFR and others would fight you on this.
Piston angle , was a mistake I was referring to the head angle as in my pervious post .

what do you want Quickin? YES a BBC can acheive more than an LS once you pass the limits of the CI limitations on the LS blocks. but not before.

There are pleanty of LSX out there in the 1000hp range, search button works wonders, and its about the same price as the BBC versions.

KHShapiro

iTrader: (10)

gearhead1186 , for ease of the build i would prob do a BBC .
Why, cost. what cost, the cost of the conversion and hunting down parts. getting the engine right where you want it and not some company that sends you motor plates and tells you where they want you to have it. Headers, where do you get LS headers for a G-body.. ( it is a G-body right, chevelle?) did you car come with a BBC , maybe you wont have to change springs. Converting to late model regs can be costly and very time consuming. Stick with the BBC idea, either way it doesnt really matter how you get there just as long as you do... 9sec will be in your future anyway with a proper build.
Good Luck to you

PICNIC_GEORGE

iTrader: (3)

I doubt much stronger if any. The heads are bigger(NOT BETTER) and the bore spacing is larger which are in the BBCs favor. The weight and and valve train geometry are not in the big blocks favor.

The original 454 block in a 70 chevelle was slightly over 300lbs I believe. An aftermarket aluminum big block is around 100 give or take. The old cast cranks were heavy as hell. There is a big difference.
Stock BBC heads don't kill stock ls7 heads. But a bad *** set of 360 trick flows do...

I agree with the rod angle ratio. Its not that big of a deal.

When you get a 235cc head for an LSX and a 357cc head for a BBC there is a big difference. But the 235cc LSX heads usually aren't that far off flow wise to a 345+cc big block head.

slammer454

There isa defenite price advantage using a BBC. But your going to ave to sacrifice in the weight category. But you can make 600HP for 10K with a BBC, and on pump. My boss copied an engine out of super chevy recently, he simply took a original block, prepped it, and then used an Eagle rotating assembly and an Edelbrock top end kit. We haven;t dyno'd it yet, but SC pulled 606HP and 598 TQ at 5500 RPM, Pretty impressive.

true, remember the pump gas drags? 414 CI on spray vs. 606 CI HEMI N/A. guess who won? 414 on spray.

KHShapiro

iTrader: (10)

Not to be an *** but you cant compare that with things being equal.
Just like you cant really compare a 1/4 car and an 1/8 mile car when reading there time slips.

PICNIC_GEORGE

iTrader: (3)

My bad I thought you were talking about rod ratio. The valve angle is better on an LSX and so is the geometry. That's why you don't need 350cc heads to flow 350cfm at .600 lift. Much more efficient for sure.

Weight difference between an iron big block and all aluminum small block is HUGE.

But like said no replacement for displacement. Big blocks will always make more power.

Orr89rocz

iTrader: (13)

this thread makes me want to go bigblock for my Camaro. lol

Busted Knuckles

You can build an LS2 stroker longblock for not much more than a Brodix aluminum block costs - close to $5K and it will STILL be heavier than an LS engine. Dart has a CNC big block that is one beautiful piece of engineering but costs upwards of $10K,

I don't think we'll ever see an LS series engine taking the place of the sure 'nuff big-inch engines, but for the majority of bracket racers in the 9 second range, the big block's days as ruler of the roost are just about over.

There's still nothing like a big-inch big block tucked between the framerails of a muscle car. Put a huffer on it and it becomes pretty much unstreetable, though.

IMHO, they're both here to stay for the forseeable future. It's a matter of preference, both can make more reliable power than you can hope to hook up.

Hell, I'm gonna build one of each - the LS for my Corvette and a 565 for a shortwide street truck. They'll have completely different manners but both will serve the purpose they were built for quite well.

Quickin

Its not just cubic inches that are an advantage over a LSx. The heads on a BBC 427 will allow it to make ALOT more power than the BEST LSx heads on an LSx 427......................don't you agree with that?

If you're talking about the GM iron LSX, it'll be pretty damn reliable. But an aluminum 1,000 hp LSx is running at its limits and is not as reliable as a BBC at 1,000 hp. Nowhere near.

And its not me that wants the BBC, the thread started does, I'm waiting on a tall deck iron LSX to do my 481ci so it'll bolt right into my WS6. If a badass 1,000 hp PUMP GAS 632 BBC would fit without a crazy amount of fabbing, I would definitely do it!!!!!!

.

KHShapiro

iTrader: (10)

I don't. But i am not an engineer either. Maybe AFR , DART or ETP might step in and post up. i am more than happy to be shown something that i think is right to be proven wrong.


Can you list some examples of LSX aluminum Block failures. just the block and not a part that broke and cracked the block. I know of one , which wasnt a failure so to speak. When W2W ( i think it was W2W, maybe it was Katech) tore down a motor that was in the 1400 FWHP range they noticed the mains started to walk and suggested putting a girld on to prevent that from happening.