Ls motors vs Early gen SBC
04-04-2012, 03:46 PM
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Ls motors vs Early gen SBC Hello, I know I am probably going to get a biased response but I wanted to look into which would be better to build for the money. A 400 sbc or a LS motor 6L. I already have the 400 and If I go with that I am looking to make it a roller motor and put vortec heads on it. I have looked at this article
and I would copy this build its says it would make around 525 ft lbs @3500 and 430 hp@ 5000. They are doing this for 6k which I still feel is on the high side.
I have looked at many LS builds and the peaks are much higher in the rpm curve(also havent seen a lot of torque like above). Seeing that this will be a daily driver that will get hammered on when I can maybe on some back roads or the strip I am curious if I should not be looking at LS builds because of the rpms they need. I have yet to see a very torquey Ls build that has low rpm torque.
Long story short. How much to build a LS motor with as much torque possible at low rpms and what would the cost be? I also would want to make swap the EFI out for a carb. So is it worth it or stick with 400 sbc. I know it a matter of opinion but just curious.
When I build a motor I want to do it right the first time and do it once. I do not have a car to put it in yet but I want to find a hot rod such as 47-57 truck or a similar year car maybe older.
Any help is appreciated. Thank you
and I would copy this build its says it would make around 525 ft lbs @3500 and 430 hp@ 5000. They are doing this for 6k which I still feel is on the high side.
I have looked at many LS builds and the peaks are much higher in the rpm curve(also havent seen a lot of torque like above). Seeing that this will be a daily driver that will get hammered on when I can maybe on some back roads or the strip I am curious if I should not be looking at LS builds because of the rpms they need. I have yet to see a very torquey Ls build that has low rpm torque.
Long story short. How much to build a LS motor with as much torque possible at low rpms and what would the cost be? I also would want to make swap the EFI out for a carb. So is it worth it or stick with 400 sbc. I know it a matter of opinion but just curious.
When I build a motor I want to do it right the first time and do it once. I do not have a car to put it in yet but I want to find a hot rod such as 47-57 truck or a similar year car maybe older.
Any help is appreciated. Thank you
04-04-2012, 05:56 PM
#2
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Well if you are going to build a SBC you have to remember you are using 50yr old technology that has just been upgraded some. The computer and tuning is what costs more with LS engines and the design is more efficent. Super Chevy had an article how to make over 500hp out of junk yard parts. This was from the guys who designed the LS engine.
04-04-2012, 06:11 PM
#3
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$6,000 would get you a low mileage LS motor and trans complete with everything and still leave plenty of money to upgrade. In the end you'd have all the power you want, plus like 22 mpg. No tuning with a screwdriver or playing with the gas pedal to get it to start in cold weather either.
LS is my vote.
LS is my vote.
04-04-2012, 06:15 PM
#4
"When I build a motor I want to do it right the first time and do it once."
My 68 camaro had a carbed 383. It would pull a stump. I put in a 6.0. 383 would sputter, die on hard braking, and once I had it all dialed in the temp or humidity would change and the car would be all out of whack. Carbs are a pain. I wouldn't trade the 6.0 for anything, even if someone handed me a free complete BBC.
Go with an LS motor. You want a daily driven car. Take the 6.0, put $600 LS3 heads, a $300 LS3 pull-off intake w/injectors and a 220-230 ish cam and you'll put down 400 at the wheels. Gas mileage will be greatly improved.
I do believe that the LS will cost more, but when you have a car that you can just turn the key and GO with no hassles, no worries, you will appreciate the fuel injection.
Take a look at futureuser's thread on here for his 69 camaro.
My 68 camaro had a carbed 383. It would pull a stump. I put in a 6.0. 383 would sputter, die on hard braking, and once I had it all dialed in the temp or humidity would change and the car would be all out of whack. Carbs are a pain. I wouldn't trade the 6.0 for anything, even if someone handed me a free complete BBC.
Go with an LS motor. You want a daily driven car. Take the 6.0, put $600 LS3 heads, a $300 LS3 pull-off intake w/injectors and a 220-230 ish cam and you'll put down 400 at the wheels. Gas mileage will be greatly improved.
I do believe that the LS will cost more, but when you have a car that you can just turn the key and GO with no hassles, no worries, you will appreciate the fuel injection.
Take a look at futureuser's thread on here for his 69 camaro.
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04-04-2012, 06:31 PM
#5
Compare a SBC vs LS at 100k after getting "hammered on" hauling around a 5000lb SUV... the SBC will usually be worn out vs the LS still going strong.
Nothing against the SBC it's just technology.
04-04-2012, 06:32 PM
#6
You are going to get a lot of LS biased opinions here for sure. We are all drinking the kool-aid, but it is real good kool-aid! For a daily driver car or truck it is hard to beat the new EFI technology. rp0029 gave you a very good recipe. I have been driving my LS1 conversion for over 5 years now and just love it. As for torque, remember that most of the gas powered Chevy trucks for the last 10 years have been LS powered.
You don't need to be afraid of the EFI, it really is pretty simple and once you get it set up, you don't need to mess with it any more.
Pat
You don't need to be afraid of the EFI, it really is pretty simple and once you get it set up, you don't need to mess with it any more.
Pat
04-04-2012, 07:28 PM
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Had 3800lb g -body w/both mild small block and mild big block both got 10ish mpg and the 454compressors ran 12.70. Have a 3600 lb g-body w/ ac low mileage 5.3 all stock truck manifolds z06 cam it gets 20mpg and runs 13.30's motor 11.54 on spray also stock truck torque converter. $1000 engine and trans $200are used cam and $500I for harness rework and flash. And it doesn't leak oil like harley
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04-05-2012, 12:03 AM
#8
"When I build a motor I want to do it right the first time and do it once."
My 68 camaro had a carbed 383. It would pull a stump. I put in a 6.0. 383 would sputter, die on hard braking, and once I had it all dialed in the temp or humidity would change and the car would be all out of whack. Carbs are a pain. I wouldn't trade the 6.0 for anything, even if someone handed me a free complete BBC.
Go with an LS motor. You want a daily driven car. Take the 6.0, put $600 LS3 heads, a $300 LS3 pull-off intake w/injectors and a 220-230 ish cam and you'll put down 400 at the wheels. Gas mileage will be greatly improved.
I do believe that the LS will cost more, but when you have a car that you can just turn the key and GO with no hassles, no worries, you will appreciate the fuel injection.
Take a look at futureuser's thread on here for his 69 camaro.
My 68 camaro had a carbed 383. It would pull a stump. I put in a 6.0. 383 would sputter, die on hard braking, and once I had it all dialed in the temp or humidity would change and the car would be all out of whack. Carbs are a pain. I wouldn't trade the 6.0 for anything, even if someone handed me a free complete BBC.
Go with an LS motor. You want a daily driven car. Take the 6.0, put $600 LS3 heads, a $300 LS3 pull-off intake w/injectors and a 220-230 ish cam and you'll put down 400 at the wheels. Gas mileage will be greatly improved.
I do believe that the LS will cost more, but when you have a car that you can just turn the key and GO with no hassles, no worries, you will appreciate the fuel injection.
Take a look at futureuser's thread on here for his 69 camaro.
There is nothing wrong with building a 400 sbc, but my junkyard 6.0 makes 500lb of torque at 3500 and more than 430hp at 5000. At 6000 it has over 500hp. Heads have never been off the motor. It has a cam as descibed above and a used vette intake. All done for much less than $6K and no peaky power. The newer 6.0's come with heads like the LS3.
04-05-2012, 01:40 AM
#9
Really is a matter of opinion but also what you want for an end result.400sbc no doubt will make more lowend torque than the lsx 6.0.That can make for quite the seat of the pants death trap feeling of a daily driver.Being carbed aswell..gas mileage will be out the window as Im sure you are well aware of.
The lsx 6.0's will have a much flatter torque curve..it wont peak and drastically drop off as harsh as the sbc would.You can still build a very nice carbed lsx 6.0 and have better mileage and a more consistent power and torque under the curve for whatever car you put it into.Efi wont be as tempermental as a carb setup once its tuned.
Money wise..the sbc will be cheaper..but by how much will depend on what parts you go with.Even at the end of the day when the numbers are crunched down..you might spend an extra $100-1500 for the initial cost of lsx swap parts required as your only set back..but the gains will be worth every penny.
The lsx 6.0's will have a much flatter torque curve..it wont peak and drastically drop off as harsh as the sbc would.You can still build a very nice carbed lsx 6.0 and have better mileage and a more consistent power and torque under the curve for whatever car you put it into.Efi wont be as tempermental as a carb setup once its tuned.
Money wise..the sbc will be cheaper..but by how much will depend on what parts you go with.Even at the end of the day when the numbers are crunched down..you might spend an extra $100-1500 for the initial cost of lsx swap parts required as your only set back..but the gains will be worth every penny.
04-05-2012, 05:51 AM
#11
Don't confuse induction method with the motor. If all you want is easy starts and driving you can get aftermarket EFI for a first gen too. Going with an LS pullout just makes it easier (and cheaper) to get used EFI parts that all work together.
Gas mileage is heavily dependent on proper gearing. I'm not sure if an old SBC has a built in disadvantage in that area, but I do know they where usually mated to non overdrive transmissions. Not really a fair comparison.
Where LS motors do shine compared to first gens is they seem to make more power with much less cam. That keeps them streetable and raises the performance potential.
The comment about engine life is interesting too. 100K miles seems like nothing to these motors. However EFI might have a lot to do with that. It is a well know fact that carbs do a poor job of metering fuel when cold and end up washing fuel into the oil greatly shortening the life of the motor. Plus even the cheapest modern oil is also better than the stuff available back in the 60's and 70's, so again could you use these things to improve the life of a first gen?
By the way I run a carb'd LS2. These motors carb up nicely.
Gas mileage is heavily dependent on proper gearing. I'm not sure if an old SBC has a built in disadvantage in that area, but I do know they where usually mated to non overdrive transmissions. Not really a fair comparison.
Where LS motors do shine compared to first gens is they seem to make more power with much less cam. That keeps them streetable and raises the performance potential.
The comment about engine life is interesting too. 100K miles seems like nothing to these motors. However EFI might have a lot to do with that. It is a well know fact that carbs do a poor job of metering fuel when cold and end up washing fuel into the oil greatly shortening the life of the motor. Plus even the cheapest modern oil is also better than the stuff available back in the 60's and 70's, so again could you use these things to improve the life of a first gen?
By the way I run a carb'd LS2. These motors carb up nicely.
04-05-2012, 09:34 AM
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"When I build a motor I want to do it right the first time and do it once."
My 68 camaro had a carbed 383. It would pull a stump. I put in a 6.0. 383 would sputter, die on hard braking, and once I had it all dialed in the temp or humidity would change and the car would be all out of whack. Carbs are a pain. I wouldn't trade the 6.0 for anything, even if someone handed me a free complete BBC.
Go with an LS motor. You want a daily driven car. Take the 6.0, put $600 LS3 heads, a $300 LS3 pull-off intake w/injectors and a 220-230 ish cam and you'll put down 400 at the wheels. Gas mileage will be greatly improved.
I do believe that the LS will cost more, but when you have a car that you can just turn the key and GO with no hassles, no worries, you will appreciate the fuel injection.
Take a look at futureuser's thread on here for his 69 camaro.
My 68 camaro had a carbed 383. It would pull a stump. I put in a 6.0. 383 would sputter, die on hard braking, and once I had it all dialed in the temp or humidity would change and the car would be all out of whack. Carbs are a pain. I wouldn't trade the 6.0 for anything, even if someone handed me a free complete BBC.
Go with an LS motor. You want a daily driven car. Take the 6.0, put $600 LS3 heads, a $300 LS3 pull-off intake w/injectors and a 220-230 ish cam and you'll put down 400 at the wheels. Gas mileage will be greatly improved.
I do believe that the LS will cost more, but when you have a car that you can just turn the key and GO with no hassles, no worries, you will appreciate the fuel injection.
Take a look at futureuser's thread on here for his 69 camaro.
As for gas mileage I do believe and understand the Ls motor will win but shouldnt we factor in the overdrive trannies compared to the old muncies or th350s hooked up to early gen motors?
Also, what is an Ly6 motor??? I see that in the "futureuser's" build?
A quick question about stroker LS. If I was to stroke a 6L what is the biggest you can go before having to worry about clearances?
04-05-2012, 09:41 AM
#14
The LS is just a better design, 50yr newer technology. I read an article in hotrod about converting an old sbc or maybe it was an LT1 car to an LS ignition system alone and it gained 25hp over a distributor, and thats just the ignition system let alone all the other little improvments. Thats why mod for mod the LS makes more power, although gen 1 stuff is cheaper.
This reminds me of a guy at our local track who has a built 406 gen 1 in his 83 camaro and a buddy of mine with ported ls6 heads and 226/234 cam ran a better ET on motor with 60 less cubes than he did, stressed the guy with the 406 right out lol. I would do the LS if it was me, better gas milage, better driveability, no carb to screw with, will last longer. Nothing wrong with gen 1 stuff but If I had a choice it would be LS.
This reminds me of a guy at our local track who has a built 406 gen 1 in his 83 camaro and a buddy of mine with ported ls6 heads and 226/234 cam ran a better ET on motor with 60 less cubes than he did, stressed the guy with the 406 right out lol. I would do the LS if it was me, better gas milage, better driveability, no carb to screw with, will last longer. Nothing wrong with gen 1 stuff but If I had a choice it would be LS.
04-05-2012, 09:43 AM
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Don't confuse induction method with the motor. If all you want is easy starts and driving you can get aftermarket EFI for a first gen too. Going with an LS pullout just makes it easier (and cheaper) to get used EFI parts that all work together.
Gas mileage is heavily dependent on proper gearing. I'm not sure if an old SBC has a built in disadvantage in that area, but I do know they where usually mated to non overdrive transmissions. Not really a fair comparison.
Where LS motors do shine compared to first gens is they seem to make more power with much less cam. That keeps them streetable and raises the performance potential.
The comment about engine life is interesting too. 100K miles seems like nothing to these motors. However EFI might have a lot to do with that. It is a well know fact that carbs do a poor job of metering fuel when cold and end up washing fuel into the oil greatly shortening the life of the motor. Plus even the cheapest modern oil is also better than the stuff available back in the 60's and 70's, so again could you use these things to improve the life of a first gen?
By the way I run a carb'd LS2. These motors carb up nicely.
Gas mileage is heavily dependent on proper gearing. I'm not sure if an old SBC has a built in disadvantage in that area, but I do know they where usually mated to non overdrive transmissions. Not really a fair comparison.
Where LS motors do shine compared to first gens is they seem to make more power with much less cam. That keeps them streetable and raises the performance potential.
The comment about engine life is interesting too. 100K miles seems like nothing to these motors. However EFI might have a lot to do with that. It is a well know fact that carbs do a poor job of metering fuel when cold and end up washing fuel into the oil greatly shortening the life of the motor. Plus even the cheapest modern oil is also better than the stuff available back in the 60's and 70's, so again could you use these things to improve the life of a first gen?
By the way I run a carb'd LS2. These motors carb up nicely.
Seeing that you have a carbed LS motor how do you feel it is on gas mileage??? Also do you see a big difference between the two good or bad? I just prefer a carb because there is no use of computers and I think trouble shooting is easier. Did you go with the coil pack swap or the front distributor style for the swap?
04-05-2012, 10:05 AM
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LS gets my vote. Once I did my first swap, I've never touched a carb'd sbc ever since. Everything we build is LS something or another. If you make the change, you will be glad you did.
04-05-2012, 10:25 AM
#17
The LY6 and its replacement the L96 are standard 6.0s found in current generation HD trucks. They are great because they use the rectangular port heads found on more expensive 6.2L all aluminum engines in cars and escallades. Also, they don't have dod, so you can slide in a performance cam without pulling the heads and changing the lifters. Finally, the car intakes bolt right on. These motors are a valvetrain upgrade away from 500hp. They come with vvt and keeping it is optional.
04-05-2012, 07:14 PM
#18
Everyone, thank you for the info. A few more things. How much is a 6L going for with a t56? Also, I would still think I would like to swap the Efi to carb. I live in cali so there will not be much to deal with cold starts. So how much would it cost to do a carb swap. Some of these things affect cost vs an early gen. I am aware that EFI may have it advantages but still want to know.
As for gas mileage I do believe and understand the Ls motor will win but shouldnt we factor in the overdrive trannies compared to the old muncies or th350s hooked up to early gen motors?
Also, what is an Ly6 motor??? I see that in the "futureuser's" build?
A quick question about stroker LS. If I was to stroke a 6L what is the biggest you can go before having to worry about clearances?
As for gas mileage I do believe and understand the Ls motor will win but shouldnt we factor in the overdrive trannies compared to the old muncies or th350s hooked up to early gen motors?
Also, what is an Ly6 motor??? I see that in the "futureuser's" build?
A quick question about stroker LS. If I was to stroke a 6L what is the biggest you can go before having to worry about clearances?
04-05-2012, 07:17 PM
#19
AHHH sorry I see you touched upon the tranny situation already.
Seeing that you have a carbed LS motor how do you feel it is on gas mileage??? Also do you see a big difference between the two good or bad? I just prefer a carb because there is no use of computers and I think trouble shooting is easier. Did you go with the coil pack swap or the front distributor style for the swap?
Seeing that you have a carbed LS motor how do you feel it is on gas mileage??? Also do you see a big difference between the two good or bad? I just prefer a carb because there is no use of computers and I think trouble shooting is easier. Did you go with the coil pack swap or the front distributor style for the swap?