Please explain how an EFI SBC @600hp (or any HP) is harder to drive then an LS @ same power level. Now I will give you if comparing a carb to any EFI platform EFI will always win the driveability contest.
Everyone is going LS, is it the best option if you are already set up for a SBC?
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Please explain how an EFI SBC @600hp (or any HP) is harder to drive then an LS @ same power level. Now I will give you if comparing a carb to any EFI platform EFI will always win the driveability contest.
I see what he is saying, a 600hp SBC is likely going to be cammed up high, high compression.... and likely not ideal for daily driving. I say that argument is out the window under 450 to maybe even 500 hp. but again I am happy around 350hp, I want this to be a summer driver. another thing mentioned that is also a big thing for me, you get up in the high hp range and everything else in the car is going to need upgrades, transmission being a big one, the car already has a 8.5 so I am covered there. I didn't mention that this is a 86 T top 442, number one I don't think T top cars should have big hp in them personally and that is due to body twist and number 2 this is a low production car that I don't want to destroy
Anything above 400 HP, a G body (even a low mile rust free one) is going to need frame and body reinforcing so it doesn't twist apart. If your car has any rust problems like rusted out frame or body mounts you will need to fix such issues first.
While the LS has its pros, it also has its cons like every engine does. The LS oiling system isn't as good as the SBC's, it is why LS7s and 9s use a dry sump setup because it is a retrofit bandaid. The shallow oil pans and deep skirt blocks are bad for oil control and the oil pump being crank driven increases cavitation. The deep skirt block also is bad for crankcase ventilation and why LS motors have PCV issues.
Another issue is that tuning LS motors is very expensive. The tuning software starts at $700 and is another $100 for every additional car you want to tune with it. Also you need to know how to read and use 3D curve mapping and may need to take courses for it. That is why many opt to go to a tuner shop instead who usually charges at least $250 a tuning session and it may take more than one to get things right.
Because G bodies were never designed for LS motors, installing one can be expensive and there are some legal issues if you live in a strict emissions area. Stock LS motors use a enhanced EVAP system that is not compatible with factory G body gas tanks. People have had their LS swapped cars failed over this and heard of at least one guy who was forced to go with a Erod crate kit to replace his used LS swap. The Erod versions of the LS motors do not come with an enhanced EVAP, just a plain EVAP making them compatible and legal for G bodies. Also reflashing a PCM is considered emissions tampering and illegal. Some areas do check the PCM to see if it has ever been reflashed. Whenyou install a OBD2 motor into your preOBD2 car it is now considered a OBD2 car and must meet all the regs for it, such as installing a OBD2 ALDL port and SES light on your dash for the inspectors. Even a Erod kit can be redered illegal if its PCM is reflashed. Not sure if deleting VATS is considered tampering by the govt, hopefully not.
Aluminum LS blocks use thin nonremoveable iron cylinder sleeves that are cast into the block which limits overbore to just .010. The LS7 and I think the LS9 use pressed in sleeves that can be pressed out and replaced like most sleeved engines. Iron LS blocks are sleeveless direct bores like the classic gen blocks.
While the LS has its pros, it also has its cons like every engine does. The LS oiling system isn't as good as the SBC's, it is why LS7s and 9s use a dry sump setup because it is a retrofit bandaid. The shallow oil pans and deep skirt blocks are bad for oil control and the oil pump being crank driven increases cavitation. The deep skirt block also is bad for crankcase ventilation and why LS motors have PCV issues.
Another issue is that tuning LS motors is very expensive. The tuning software starts at $700 and is another $100 for every additional car you want to tune with it. Also you need to know how to read and use 3D curve mapping and may need to take courses for it. That is why many opt to go to a tuner shop instead who usually charges at least $250 a tuning session and it may take more than one to get things right.
Because G bodies were never designed for LS motors, installing one can be expensive and there are some legal issues if you live in a strict emissions area. Stock LS motors use a enhanced EVAP system that is not compatible with factory G body gas tanks. People have had their LS swapped cars failed over this and heard of at least one guy who was forced to go with a Erod crate kit to replace his used LS swap. The Erod versions of the LS motors do not come with an enhanced EVAP, just a plain EVAP making them compatible and legal for G bodies. Also reflashing a PCM is considered emissions tampering and illegal. Some areas do check the PCM to see if it has ever been reflashed. Whenyou install a OBD2 motor into your preOBD2 car it is now considered a OBD2 car and must meet all the regs for it, such as installing a OBD2 ALDL port and SES light on your dash for the inspectors. Even a Erod kit can be redered illegal if its PCM is reflashed. Not sure if deleting VATS is considered tampering by the govt, hopefully not.
Aluminum LS blocks use thin nonremoveable iron cylinder sleeves that are cast into the block which limits overbore to just .010. The LS7 and I think the LS9 use pressed in sleeves that can be pressed out and replaced like most sleeved engines. Iron LS blocks are sleeveless direct bores like the classic gen blocks.
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What did I spell wrong in my last post? I did see the one capitalization and missing apostrophe but keep in mind I was on my cell lol.
Between the fundamentally better heads and the optimized valvetrain, you can build more power with the LS by way of better flow and port velocity and camshafts with much more aggressive lobe profiles and ramp rates. Nevermind EFI, as I said...it's a plus that you can use factory parts (all the sensors and the computer in my car are used GM factory parts). I daily drive a 231/235 @ .050 cam with .635/.610 lift on a 112 LSA. Running something like that in a 350 chevy, not only won't make the same power without enormously expensive heads, will result in low vacuum and a terrible idle. I lope a bit at 800rpm, but it drives silky smooth. Yeah, the EFI helps, but a carb setup would drive just as well. Again, it's all in the lobe profile and heads. My car traps almost 120mph, so it's making a pretty good helping of power.
I went looking for an article from one of the magazines that built a 550hp LS1 and then built a 550hp 355 SBC and compared the two. The LS1 was fairly mild. The 355 was VERY aggressive to make the number. Couldn't find it though. Can't even remember what magazine it was, but it illustrated the point I'm making really well.
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What you say about rust is true, however 400hp is a walking the the park with a g-body. Remember kids, it's torque that will twist your frame. That said, I run 11.67 @ 119.6 right now and I'm on a stock non-reinforced frame. And I have t-tops. No twist here and I launch flat and level. Granted, I do have all aftermarket tubular suspension parts, a giant drag swaybar, oh...and I did tie the upper shock mounts together. I do need to replace the rotten body bushings, but that's for a different reason entirely.
A lot of what you say isn't correct concerning the LS motor. Early (like pre '99) engines had crankcase breathing issues from web to web because there was no opening between the webs for anything to go anywhere. This was fixed. Dry-sump was added to Corvette ZO6 (LS7) and ZR-1 (LS9) as well as Camaro Z28 for both packing reasons and because they are road-race inspired/purposed. This is pretty standard for any engine pulling heavy and sustained lateral g-forces. Stock wet-sump oil pans are better than SBC/BBC oil pans and pumps. They are not shallow except for the odd Corvette pans that exist only because of packaging reasons. Those suck. The deep skirt block is NOT any reason for the PCV issue, that's completely unrelated. The PCV sucks in heavy oil vapor because of the aeration in the valvecovers. The PCV was moved to the valley cover in later engines and the problem was largely solved, but there's still plenty of oil vapor to separate before letting the intake suck it back in. So, we run an inexpensive catch-can...problem solved.
Interesting that you focus on only the tuning cost..and you have come of your prices a bit off. It's $650 for the HP Tuners Pro and you can tune 4 cars (8 credits) with it. Only $50 more for each additional car past that. But, you're forgetting the cost of a wide-band o2 sensor which, IMHO is a MUST for tuning and they run about $150. You can tune by LTFT and STFT, but you really shouldn't. Independent dyno tuners likely won't touch your car for less than $500, but fly-by-night guys will do it on the street for $100. But, you get a factory EFI system that is very complex, has individual coil per plug, etc. How much does it cost to put EFI on a SBC?
Physically installing the LS in my g-body was actually pretty cheap. Used headers from a 4th-gen f-body modified to fit $100. Tubular crossmember for the 4L80E $135 shipped. Adapter plates $45....and...that's it. Stock radiator and Silverado upper hose and Ford E350(upper) for the lower hose. Couple more normal knicky-knack things like the throttle cable and integrating the steam vent, done deal. Sorry if you live in an emissions state. That sucks for you. BTW, my car meets all emissions checks in my state (no visual), just OBD2 ALDL and SES check. It wouldn't pass a sniffer though, no cats, but we don't have that to worry about here.
LS blocks can have their stock sleeves bored-out and replaced, and many do. It's a common way for LS2 4" bores to become 4.125" bores since the LS2 block is considerably cheaper than an LS7 block. For a simple rebuild though, if .010 doesn't do it, it's cheaper to just source a fresh block! Yes, the LS7 and LS9 use pressed sleeves and both blocks are not very cheap. And sure, the iron blocks are direct bores just like the classic SBC...but they are iron.
I disagree, 400 hp is stress a gbody was never designed to take with their thin gauge, mild steel construction. 110 hp out of my old V6 was enough to crack my roof just normal driving. At 400 I have seen glass blow out from body twisting and lower LCA mounts twisted and cracked rear frame rails.
$150 is still a lot cheaper than $650 plus no credit nonsense. All I know is I have a friend with an 11 Vette and a LS2 swapped 85 Monte, he paid $700 for his HP Tuners Pro and had to pay an extra $100 to be able to use it on the Monte too. Personally I am happy with my Qjet which is just as good as EFI for street driving and I can tune the a/f mixture with a dwell meter. If I was more into drag I might be more concerned about EFI.
What I said is indeed correct sir. Due to the deep skirt factory block, the LS crankshaft is constantly rolling around in the oil supply, and as RPM levels increase, the factory pans can actually become empty, starving the engine of oil. Even the LS7 dry sump setup could not completely fix it, and it is incorrect that it is just packaging as you claim. The oil pumps in past engines like the small-block Chevy was driven from the camshaft, which turns at half engine speed, and the LS-style pumps are driven at full engine speed from the crankshaft. The issue that raises its ugly head in this situation is cavitation. The factory pan designs are very shallow, and the majority of the oil volume is housed up inside the deep-skirt block. GM attacked the oiling issues by creating windows as you stated, inside the factory blocks, allowing the oil a way to move throughout the lower half of the engine, but this also creates extra windage. This extra windage is why LS PCV system suck up so much oil and why SBCs last longer on road courses than LSs.
The LS also has alot of internal oil “leakage”. A stock SBC takes 5 gallons per minute of oil at 6,000 RPM to lubricate everything, a LS uses 18 gallons per minute at 6,000 RPM because of greater leakage. There is very little metal to hold the main bores and cam tunnels in place because of the windows and can lead to wear problems. All cams flex a little and it’s usually no big deal, but in the LS the cam and crank are like noodles in there, and it wipes out bearings and lifters. I am not saying LS engines are bad, but like everything they are far from perfect. There is a reason why the new LT series is a complete redesign over the LS series.
About installing a LS you forgot custom driveshaft, exhaust piping, wiring harness, oil pan, belt drive accessories, etc. Also using a stock normal flow rad with a reverse flow engine isn't a good idea as it promotes air pockets. Should plan on installing a proper reverse flow rad soon. Most places that I see selling used LS motors like junkyards usually sell them piece meal so they add up quickly, but that may just be my area.
States are supposed to plug into your ALDL port and scan to see if the PCM has ever been reflashed. If you delete the gas tank pressure sensor they should detect it and fail the car, no need of a visual check as they can scan for deleted stuff that should be there. In fact they are supposed to check enhanced EVAP pressure readings to detect leaks, no readout at all means tampering.
Boring out the stock sleeves is expensive, plus the block must be machined to accept aftermarket sleeves, a better shape block is cheaper. That is why a used iron block is a safer bet and to be leary of too good prices for used aluminum LS blocks.
$150 is still a lot cheaper than $650 plus no credit nonsense. All I know is I have a friend with an 11 Vette and a LS2 swapped 85 Monte, he paid $700 for his HP Tuners Pro and had to pay an extra $100 to be able to use it on the Monte too. Personally I am happy with my Qjet which is just as good as EFI for street driving and I can tune the a/f mixture with a dwell meter. If I was more into drag I might be more concerned about EFI.
What I said is indeed correct sir. Due to the deep skirt factory block, the LS crankshaft is constantly rolling around in the oil supply, and as RPM levels increase, the factory pans can actually become empty, starving the engine of oil. Even the LS7 dry sump setup could not completely fix it, and it is incorrect that it is just packaging as you claim. The oil pumps in past engines like the small-block Chevy was driven from the camshaft, which turns at half engine speed, and the LS-style pumps are driven at full engine speed from the crankshaft. The issue that raises its ugly head in this situation is cavitation. The factory pan designs are very shallow, and the majority of the oil volume is housed up inside the deep-skirt block. GM attacked the oiling issues by creating windows as you stated, inside the factory blocks, allowing the oil a way to move throughout the lower half of the engine, but this also creates extra windage. This extra windage is why LS PCV system suck up so much oil and why SBCs last longer on road courses than LSs.
The LS also has alot of internal oil “leakage”. A stock SBC takes 5 gallons per minute of oil at 6,000 RPM to lubricate everything, a LS uses 18 gallons per minute at 6,000 RPM because of greater leakage. There is very little metal to hold the main bores and cam tunnels in place because of the windows and can lead to wear problems. All cams flex a little and it’s usually no big deal, but in the LS the cam and crank are like noodles in there, and it wipes out bearings and lifters. I am not saying LS engines are bad, but like everything they are far from perfect. There is a reason why the new LT series is a complete redesign over the LS series.
About installing a LS you forgot custom driveshaft, exhaust piping, wiring harness, oil pan, belt drive accessories, etc. Also using a stock normal flow rad with a reverse flow engine isn't a good idea as it promotes air pockets. Should plan on installing a proper reverse flow rad soon. Most places that I see selling used LS motors like junkyards usually sell them piece meal so they add up quickly, but that may just be my area.
States are supposed to plug into your ALDL port and scan to see if the PCM has ever been reflashed. If you delete the gas tank pressure sensor they should detect it and fail the car, no need of a visual check as they can scan for deleted stuff that should be there. In fact they are supposed to check enhanced EVAP pressure readings to detect leaks, no readout at all means tampering.
Boring out the stock sleeves is expensive, plus the block must be machined to accept aftermarket sleeves, a better shape block is cheaper. That is why a used iron block is a safer bet and to be leary of too good prices for used aluminum LS blocks.
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Been another interesting post - the fact is the SBC is old school, it's has been out there since the 50's with not much change. The LS is the next generation utilizing the latest tech. It's like comparing an old flip phone to the new ones. Both get the job done but what are you willing to pay for the bells and whistles
allot of stuff here. one thing I will agree with is it is not cheap to install one of these, I have added up what it would cost and I was well over 3000 dollars without all of the little stuff that adds up fast. if I was shooting for 600-700hp I will agree that the LS is the way to go. 400hp is about my tops, i save my big HP for my boats. another thing to note is everyone is comparing to a carbed old school 350, the engine i am using is a late model vortec block that is actually a bit different than an old 1950s block, in my opinion they are the only SBC i will build.
on another topic, since i have a 442 i have caught plenty of crap for putting a chevy engine in an olds. with the arguments i am hearing with people saying that an LS is modern and a bunch better than even a fuel injected SBC, why would anyone want to run a BOP engine in todays world? they never came with fuel injection, factory roller cams or serpentine setups with the exception of a few like a 307 with a roller cam.
on another topic, since i have a 442 i have caught plenty of crap for putting a chevy engine in an olds. with the arguments i am hearing with people saying that an LS is modern and a bunch better than even a fuel injected SBC, why would anyone want to run a BOP engine in todays world? they never came with fuel injection, factory roller cams or serpentine setups with the exception of a few like a 307 with a roller cam.
I always try to keep costs mostly out of these discussions. Unless those cost are retail prices. Because you or I can source part x for a great price that does not mean that is the cost for everyone. We can debate SBC vs LS pros cons till the next gen of engine is released. It is mostly a personal choice to install whatever power plant you want. My engine makes a fair amount of HP/Tq and with a Carb I had to compromise driveability and performance to find a "happy" medium so It was ok on street and performance. When I switched my 383SBC over to aftermarket EFI I no longer had to compromise and could tune it for max output and mild street manners. Aftermarket customizing support for LS is rapidly increasing which is making swaps easier, but it is still a process of a lot of modifications and custom parts made or bought to get an LS motor/trans and other required parts to install a LS whereas a SBC setup is a direct bolt in.
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