gearhead1186

iTrader: (8)

I need a mill for my 70 chevelle.. original plan was an EFI 540 with an F1R procharger.. now ive been reading about all this LS excitement and it tempts me.

The car is going to be a 65% street 35% strip.. goal is have about 1000 crank hp and run 9's

Plan is to take off the belt or lower boost on street so power is manageable ~ 650 (one fuel curve) and increase boost or put belt on for 1000 hp at track (second fuel curve).

Give me a good argument on why I should build an LS2 or LSx instead of an EFI BBC

LSInnovations

iTrader: (7)

"Go LS, not BBC."


Hope you're convinced.

IFRYRCE

iTrader: (3)

Because it's new technology. General Motors built off experiences with the BBC and SBC to build a completely new line of motors, the LS. They took what worked, used it, and trashed what didn't.

Basically, an LS1 can do with 346 cubes what a BBC would be lucky to do with 402. And that's with 40 years of experience on the BBCs side, and 10 on the LS motor's.

gearhead1186

iTrader: (8)

Can we be a little more specific here... use an LS2 stroked or an LSX compared to an EFI 540... they can both make 1000hp with a procharger... but why should I build an LS as opposed to an EFI BBC.. why should I go thru the trouble of the swap?

flynlow3

iTrader: (2)

Reliability! Things are built to a tighter spec and newer technology is great! Its like asking a hungry man, do we go club a deer or use this high powered rifle to feed our family tonight. Do you want to eat now? If you would choose to shoot the deer with a rifle then logic tells me you want to go with an LS motor.

gearhead1186

iTrader: (8)

hah i like the analogy... but how much will I really benefit from new technology in a muscle car that will only get about 5k miles a year.... if that much..

If both an LS and BBC bolted right in it would be an easier choice... but since there is alot of work to put an LS into a chevelle, the LS is going to need alot going for it... and I'll need a good argument showing that..

Quickin

Do the BBC. And 1,000 hp in a BBC won't be as much on edge as a 1,000 hp small block LS enigne. 5,000 miles a year....BBC all the way, same power for probably alot less money.


.

gearhead1186

iTrader: (8)

thanks quickin.. that was my train of thought.. I just wanted to see if there was a really good argument for swapping in an LS based block for my goals...

99DWPTA

iTrader: (10)

i dont see any need for 100hp to go 9's with the ls motor. i believe the 650 would get you there!
I dont see any reason to spend the extra bucks. if you want a nice show car to pop the hood to show it off a nice ls motor in there will bring attention. got any pics of the car?

Quickin

As awesome as the LSx blocks are, it's not gonna out-do a BBC. Plus, you're gonna spend $20,000 or more to get 1,000 reliable hp out of an LSx blocked engine with forced induction. Drop a BBC in there and it'll last a long long time.


.

Quickin

1,000 crank HP is what he wants.

650 crank HP in an LSx won't go 9's in 1970 Chevelle.

.

jermzz

iTrader: (18)

+1 for your application, I dont think the coolness factor outdoes the work / extra money you're gonna need to get the power you want.

Besides... BBC is a whole different kinda power....

gearhead1186

iTrader: (8)

thanks for your input guys... BBC was pretty much what I had my heart set on.. I just wanted to see if it was worth the work to put in an LS over a BBC.. I posted this same topic at chevelles.com but somehow it turned into a SB vs. LS debate and nobody posts anything relative to LS vs BBC anymore.

99DWTA, I dont have any shots handy... I just got her and I tucked her away for the winter. Shes a project and needs TLC so it doesnt look like much yet.

Stang's Bane

iTrader: (22)

You will run a faster time with a ls motor and equal power. Less weight...

Twin76mmTA

iTrader: (1)

Good luck making the same power as a BBC with a ls motor for the same price and have it be realiable, In the end there is no replacement for displacment.

SDB

iTrader: (7)

I love the LSx motor, and a F1A on a built 454 small block with ETP heads and sheet aluminum intake would make all the power you would ever need (1500 I would imagine)...BUT for the money and especialy for a classic muscle car, this is what I would do:

http://www.ultrastreet.net/632_1000_bd.asp

$21,000 for a complete 632 pump gas daily driver that makes 1000 hp and 865 lb/ft tque without any power adder. A simple 250 shot plate system would make 8's possible in your car I would imagine, probably mid 9's on motor with this engine alone.

Quickin

No doubt, because of weight only. But the price tag would be alot more and at the same power levels the BBC would be running EASY compared to the LSx. Longevity and reliability will come with the BBC, power levels being equal.



.

gearhead1186

iTrader: (8)

thanks a bunch guys.. i wouldnt expect guys on an ls forum to be so unbiased..

what im tossing thru my head now is whether I should go with my originally planned 540 w/ procharger or the possibly cheaper 572+ cubes with a NO2 shot...

man i love thinking about this kinda stuff

slammer454

Yep, Shafiroff has a pump gas 632 putting out 1000HP for around 20K i believe.

gearhead1186

iTrader: (8)

Ya thats exactly what I mean.. If Im going to go with a tall deck might as well do it right..

Only thing is with the original plan of a procharged 540... without the blower belt on the engine (for street driving) the car would be more street friendly as the tires wouldnt melt underneath me if my right foot fell a half an inch.. figure a 9.0 compression 540 with a blower type cam wuld make "only" about 650 hp without the blower belt on...

The n/a 632 would make goobs of power even without spray so I would need new tires every time I take her out on the street.

Ahhh decisions....