LS6427

iTrader: (2)

Just curious about something. I'm no BBC or old school expert but I am curious about something.

With 427-454ci LSx engines making upwards of 600+ RWHP and still very streetable and reliable, what would an EFI 598ci BBC make to the wheels. Not going crazy aggressive, but with equal aggressiveness as the 600+ RWHP LSx engines are going. So build it to kick *** but not something that will be crappy on the street either.

Am I way wrong in assuming with a Normally Aspirated 598 BBC, EFI and kind of aggressive, it will put down an easy 750-800 RWHP on 93 octane?

Thanks.

BAKED

iTrader: (14)

For an experienced engine builder 750-800 rwhp would not be too difficult to do with a 598, nor would 600rwhp be hard to get out of a 454 LSX. You have to remember though, the 598 has almost 150 cubes over the 454. If you do the math if you had a 454 making 600 hp it is making 1.32 hp per cubic inch and a 598 making 800 hp. in making 1.34 hp per cubic inch.

I have an acquaintance that has a 70 model Chevelle with a 612ci.big block that was built by Bischoff (BES Engines) The engine made a little over 1100 FWHP N/A. The guy drives the car all over the place on pump gas! He said that it drives like any other cammed big block car that he's driven, not too bad I didn't think.

The Batman

iTrader: (4)

the BBC will never have the same gas mileage tho...

LS6427

iTrader: (2)

So for a weekend warrior, gas mileage not being a factor at all, on 93 pump gas, a BBC 598ci could be built to put down 800 RWHP. And be very reliable, street driving friendly, and last a couple years.

What would that engine cost from a reputable builder like Bischoff or FTM?

And I assume that engine could easily take a progressive 400-500 shot, right?

capn smokey

iTrader: (1)

Your looking at a $20,000+ build to make a reliable, streetable 800whp bbc. I looked into for a while and realized that a smaller cube FI setup is much more practical and alot cheaper.

NemeSS

iTrader: (127)

that type off bbc doesnt have a single oem chevrolet part in it.
its all aftermarket, now an lsx can use oem heads and block such as l92 and make excellent power, a well prepared 402-414ci lsx engine will make excellent power, be lighter, get better economy,lower price and so forth.

LS6427

iTrader: (2)

But it would be lucky to make 500 RWHP, 300 shy of the 800 goal. A goal is a goal. The LSx would have to be turbo to make 800 RWHP.

LS6427

iTrader: (2)

Take the long block complete BBC crate engine that Chevy offers. $14,000....720 FWHP.
http://www.crateenginedepot.com/stor...27--P6C54.aspx

What can be done to this engine to get it up to 1100 FWHP, so it will make about 800 RWHP.

How much additional dollars over the $14,000 price tag.

LS6427

iTrader: (2)

Yeah, a 408ci with an S91 turbo will whip the BBC. But there's nothing like raw N/A power, to me. To have an 800 RWHP N/A engine, plus a huge dual shot 250/250 would be pretty amazing.

BAKED

iTrader: (14)

The engine I was talking about cost the guy 34K from carb to oil pan! I agree, it's crazy but nobody said that cost was a factor. That engine is already setup with 2 foggers and when properly tuned should be able to handle more nitrous than most people would ever want to spray.

Building big power, big cube engines gets VERY expensive VERY quick LOL

LS6427

iTrader: (2)

Yeah, I figured it would be expensive. FTM has a 598ci with a small Procharger at 6psi that makes 1,000 hp on 91 pump gas, only $28,000 complete, ready to install. I thought that was a pretty good price.

NemeSS

iTrader: (127)

the way the lsx is evolving now with all the research of new heads and new blocks coming out, perhaps in a few yrs. a lsx will rival bbc engines. making as much hp n/a, a good sign is that oem ls heads are alredy at over 300cfm with stock valve angles and valves. all the new 6 bolt heads that are coming out are going to flow even better. 4.125+bores and such.

JUICED96Z

iTrader: (2)

Your on CRACK!!!!!!!!!!!!!

My old 468 BBC had old but good parts and made around 800hp on a 300 shot and lasted a good 15k miles or so, I pulled it apart and everything looked great minus the cam (threw a rocker).

PLENTY of people making 800hp out of a BBC and they drive them on the street all day long no problem, thats 800hp all motor.

Talking to the wheels here.

I had factory rods and crank with my motor and a old 636ish lift cam.

When it comes to the 454+LSX guys most street guys stick with a 427, the stroke gets a little to long for the big inch stuff for the street, some get re sleved blocks but most stick with a 427.

As fas as the gas mileage comment. If you have a 454 LSX and a 454 BBC there will not be any difference if you ask me, now compared to a 5XX then yes, thats a no brainer, you can't have big power big CUI and gas mileage.


Getting 800hp to the wheels out of a LSX with no forced induction is going to be pretty much race only.

Get a Bow tie 502 block, punch it out to whatever stroke you want, nice after market steel crank and rods (don't need forged for that kind of power), sa nice top end and there you go.

Ill never run a progressive, those are harder then crap on noids. Get it to hook out of the hole on what you want or two stage it.

I had TRW forged pistons, stock rods and crank and it held a 300 shot no problem.

I assume you have not been noticing how fast the BBC stuff is evolving? Check out the Brodix Head Hunter heads 353 CFM at like 500 lift out of the box! , and remember thats a CONVENTIONAL head and has killer exhaust flow numbers also!
The limit for the LSX stuff is like 500CUI, I know of a 632 thats on the street all the time..... I don't see the LSX stuff EVER catching up the the BBC, in the end the CUI limits of the SBC based stuff is what kills it. Yes with an SBC you can make sick power I give you Mike Moran but LSX stuff rivaling BBC? No way.

Even with factory heads flowing 300cfm with the less CUI you have to spin the motor a lot harder and beat on it a lot harder to get the HP out if it. If you have a 5-6XX BBC with a good flowing head it takes a lot less RPM to make even more power.
I was on 7 cylinders and ran a stock LS1 GTO and before I even had it floored in second gear I allready had put a few cars on him, he was in first...

THe only way I would build an LSX for me is with a big turbo.

xx_ED_xx

iTrader: (17)

yes no matter the case it is in same horsepower 454 small block and same horsepower 454 big block. There will be no difference in mileage.

LS6427

iTrader: (2)

too bad its so hard to stuff a BBC into an F-Body and keep A/C. I'd do it right now. 800 RWHP N/A...plus a dual stage 600 shot...300/300. That would just be unique and very cool to have. Just a roll racing monster. Single turbo LSX seems like the choice.

NemeSS

iTrader: (127)

all of that for a roll racing monster.
i think your goal would better be accomplished with large single supra, and u get ac too

LS6427

iTrader: (2)

I know, I'm actually one of those people that think drag racing is just about the gayest thing on the planet. To each his own I guess.

I like a car that can drive on the street, has A/C, can take corners nicely, good braking, stereo, 4 seats, and no trailor, etc.... Yet, can still do a tire change and squeeze off a 10 second 1/4 mile ET.

Its what I have now. ~500 RWHP WS6 full interior street car. I'm just more than ready to up the HP, ~500 RWHP is plain old, just a snooze. And I mean up the hp alot.

Single 94mm + 408ci = my goal plus some

Just wanted to ask a little bit about these BBC.

KCS

iTrader: (20)

LOL, this was funny.

You can easily make 600bhp with a .060 over BBC, stock crank, rods, 10:1 compression, and pocket ported iron oval port heads.

With a BBC, you have two major advantages. First is bore spacing, 4.84" vs. 4.40". This allows a bigger bore, which allows bigger valves, which allows more RPM and also allows the next advantage...more cubic inches. Max bore on an LSX block is 4.205? A stock 454 block is 4.250" and can go over 4.300" bore. 502 blocks are around 4.500" Thats an easy 509ci...

LS6427

iTrader: (2)

Yeah, there's absolutely no doubt that a normally aspirated BBC will make an LSx engine look like a Briggs & Stratton lawnmower engine in every way possible. An all-out LSx engine build will NEVER make near the power of an all-out BBC build. Its just too bad it takes $10,000 in fabbing the car alone to stuff it in a 1998-2002 F-Body. I'd do it in a second if it was easier.

ZONES89RS

iTrader: (25)

Well, this is a good little thread here...


They both have ups and downs.

BBC is heavier, but it makes up for the common block 454 to be stroked to 496+ cubes for 2500$. The common 6.0 LSx truck block, just over 400 cubes, that alone makes the big block have an advantage. The 454 can make 700 HP NA on a good budget, the 6.0 is looking at 600 HP for ALLOT more money. That alone makes the BBC gold to date. Now, when the after market is involved, so is tons of money. So, we just have to accept that Chevrolet did their thing and rules the world of HP.

So, a 496 BBC in a third gen on a single 300 shot...SUPRA KILLER FOR A FRACTION OF THE PRICE