Great thread and let me ask this since I'm about 6 months from this same decision. My frame off 78 will be a 3 season ride, no winter or extreme cold. The electric choke on the 305 carbed motor on the car ran just fine before I ripped it apart. Thinking a 383, possible efi on completion. I love the ls stuff as I have many friends with them but these arguments for LS vs carbed seems like the old motors are like still using a horse. Am I missing something?
Everyone is going LS, is it the best option if you are already set up for a SBC?
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Basically it is the same argument that occurs EVERY time any mfr make a jump to a new platform. The LS series is not this magic pile of metal and electronics that many try to oversell it as. Does the LS have advantages? The answer is a definite yes. Does the LS make a SBC obsolete? The answer is a definite no. If you are starting from scratch and want to spend the money, time and effort to convert EVERY part of your Gbody over so you can install a LS and all it's required parts including the entire fuel system, wiring and driveline, you will end up with a very good system that can grow with your desire for more power or just a reliable cruiser. The arguments of LS vs SBC mostly center around a stock Carb'd SBC against a modern EFI managed LS. In that match up obviously a LS wins just like a SBC wins over a Flat head. Quite frankly that comparison is unrealistic to a gear head looking to build power. Those building a SBC for power do not use factory parts! Then add in the availability of very advanced aftermarket EFI systems, the baseline comparison between a SBC and and LS narrow greatly. The other thing is that almost all comparisons I've seen are talking about used parts to build a LS. The cost to get a used LS into a GBody is about the same as a SBC can be built with all new parts for similar Normally Aspirated horsepower numbers. Throw in power adders and it is a different set of rules for both platforms.
I'm not cheerleading the SBC or short-selling the LS both have Pros and Cons and comes down to you the gearhead which one you want. The issue for someone making the decision is most of the time it is an apple to orange comparison they are making their decision on and that can lead to frustration when hype or cost don't match up.
The only TRUE comparison is pick a HP/TQ number and price your build out at Retail prices for every part(that does mean every nut, bolt, wire, etc) to build an SBC and then a LS to that level. Then you have all the facts you need to start your decision. That is also the point all of us gearheads start wheeling, dealing, barter, beg, borrow to get our rides to our goals because no one WANTS to pay retail if they can help it.
Good Luck on you build!.
I'm not cheerleading the SBC or short-selling the LS both have Pros and Cons and comes down to you the gearhead which one you want. The issue for someone making the decision is most of the time it is an apple to orange comparison they are making their decision on and that can lead to frustration when hype or cost don't match up.
The only TRUE comparison is pick a HP/TQ number and price your build out at Retail prices for every part(that does mean every nut, bolt, wire, etc) to build an SBC and then a LS to that level. Then you have all the facts you need to start your decision. That is also the point all of us gearheads start wheeling, dealing, barter, beg, borrow to get our rides to our goals because no one WANTS to pay retail if they can help it.
Good Luck on you build!.
I don't get the whole LS fest thing. When it first started the hype was because people were letting these engines go for really cheap, just a few hundred dollars. Once it became a popular fad, now that people are asking big money for these engines and it's just not worth it anymore. Sort of like, if we over-hyped this site and had a huge g-body event that was highly publicized the value of parts and cars would go up after that - but so would our insurance for example. If you blow up a $400 or $500 used sbc, it's nice to know you can just go find another one again and start over for around the same cost. When you buy a used LS you're taking about the same amount of risk that it could wind up being a turd just a few miles down the road, so for me I wouldn't pay the extra money unless I knew the previous owner and was getting a better deal than everyone else. Staying sbc makes the guarantee of cheap plentiful parts more likely in the future. Now that people are asking more money for the LS, it really doesn't make sense to me that people are hunting them down who are not going to capitalize on those extra horsepower and the turbo setup etc., especially if it's going into a buick / olds. If you're not going for 500 hp+ why get the LS at nearly twice the cost of the sbc then? It's just going to cost more money to maintain down the line while only offering a few additional mpg highway back. Not worth it.
After adding up all of the costs I found my self thinking about my first SBC swap I did in my 84 regal back in the day when I was a broke college kid at like 18ish and how the heck I afforded to do it. I had the good ol 3.8 and we all know the story behind getting those out from under your hood so I picked up a complete 305 for 100 bucks from a friends dad, he gave me a long shaft turbo 350 with that also but it wouldn’t work since I needed a short shaft. I found a turbo 350 from a local salvage yard for 100 bucks, had 2 6 dollar a piece motor mounts and in that engine went. The local salvage yard use to have a 50 dollar all you can carry deal going on, and I found a Malibu with a newer manifold back exhaust on it, pulled it and we used pieces of wire to hang the rest of the small parts we want onto that exhaust and walked out of there with it all, most of it had nothing to do with the engine swap. I bet I had 500 bucks into that first engine swap. After that I wanted to rebuild an engine so I went and pulled a 350 out of the salvage yard that happened to already be bored 30 over, I rebuilt it with all new rings and bearings, found an edelbrock intake in the salvage yard for it for 35 bucks and swapped out the 305. I then started with additional performance stuff with a energizer cam, headers, holley fuel pump, flowmasters, edelbrock carb, lots of aluminum dress up on the engine to make it pretty and I bet i still ended up not spending more than maybe another 800 bucks on it total. today that engine has been in about 5 different g bodies that I have owned or currently still own, the thing sounds great, it burns rubber and it has never left me stranded. Not great on gas and it isn't going to kill a corvette though. I am comparing that to the list of parts that’s needed just to bolt an LS in and its crazy to think about the cost just to bolt it into the car with accessories and its just the stock stuff, no performance parts, no dress up. the main objective I had started out with personally was to get rid of the 3.8 and have reasonable power.
Very good point in the beginning. I have bought a lot of my stuff new for the LS swap. Still found deals though.
Aside from making more power with stock parts, this ^^^ would be one of my primary factors to consider if I had to choose between an LS and SBC. Bolting in a modern engine and transmission with an OEM computer can transform any old school ride into one that has great street manners, a relatively smooth idle, and is more fun to drive. You also get programmable shift points, no leaks, BIG horsepower potential, less smell and typically better fuel economy. When GM developed the LS platform they used years of lessons learned from early BOP and Chevy designs. Not only do the factory heads outflow most aftermarket performance heads, the bottom end is stout and you can get VVT technology. Add to that the 100lb weight savings of an LS3 or L92 aluminum block and you can't go wrong. I am ready to move on from 40 year old technology.
are you talking a 70s SBC with a carb or what I am talking about with a late model vortec based engine with a all silicone seals and a modern EFI setup on top of it? heck they even make silicone seals for the older blocks now so that argument is not valid. a holley HP computer alone makes it so I can tune from a laptop
Most upgrade to newer gauges to accept the vss. Otherwise there are a couple companies making conversion boxes that will hood up to the orig speedo cable
Cablex is the first one that comes to mind. I think TCI may have one as well. It was $400 or so when my buddy did this about 8-10 years ago when he switched to 6 speed manual in his Elco.
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I am referring to a carb set up. If I had your Ram Jet set up I would likely stick with it if it met my goals of 450 + RWHP. The next step for my 86' Olds was an EFI Olds 455. That build would have cost in access of 10K to do it right. I know of similar 455 builds that have not met that HP level and have poor street manners not to mention oil leaks.. I am now going LS. I have always been an Olds purist but in this case, swapping in an LS doesn't bother me since it is a corporate GM engine. My cars are stock appearing but highly modified.
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