What's needed and is it worth it?

I think is pretty strait forward: an intake and carb and all the fixins but im not an expert lol

And in my opinion itd be worth it. you wouldnt have to deal with 5 miles of electronics and headaches

You would still need an electronic controller for the spark coils, and maybe for the trans ( depends on the trans.). Also, different motor mounts, and special connector for the trans. New Headers, and possibly different mounts for the AC and Alternator.
Without the FI and the electronic control, it's just a SBC. It's the FI and controls that give it the performance and mileage. If you want carb'd and vacuum distributor, you'd be better off building a Gen 1 small block, or even a big block.

I have kicked around the idea for a 70 Chevelle I have and grabbing a donor seems the best approach .... either a firebird or a camaro. That way you have all the wiring, computer, fuel pump; trannie .... and its the trannie situation in a corvette that would keep me from using the Corvette. A decent car goes for about 3500 in California

.... as far as the carb on a LS ... kits are out there ... edelbrock sells on and I think B Grant does also ... personally I'd stick with the FI ... but that just me!

Personally I,d stick with the efi also, the main thing the carb conversion would save is tank modifying, not cost of wiring. The main work is in the rest of the swap. Check further back in this section if you haven't yet, i,ve posted several others on this subject.
I,ve had a ls1 t/56 conversion since 02/03'. Ps ,the wiring is not that complicated if you get a factory harness modified or a new version.

All information is appreciated. Its just a thought. I'm in cali and still trying to keep some what of a good daily driver but very good performance engine. I prefer long jevity over racing. I'm debating either a 400 sbc gen1, a lt1 and ls1. I still have my original LM1 in the elco. 350 trans with 7.5 373's in the rear.

What's needed and is it worth it?

= Prime Rib with ketchup :screwy:

= Prime Rib with ketchup :screwy:
I know a few guys that would consider that a delicacy!!!

honestly keep it EFI once start doing the harnesses they are not that difficult. been swappiong these motors into everything anymore.

...
Without the FI and the electronic control, it's just a SBC. It's the FI and controls that give it the performance and mileage. If you want carb'd and vacuum distributor, you'd be better off building a Gen 1 small block, or even a big block.

No! The LS1 is a clean-sheet re-design of the SBC. The ports in the heads are HUGE and flow massive amounts of air/fuel. The crank to cam spacing is larger and all eight cylinder ports are replicated (identical) for consistency. My 6.0 (used; out of an Escalade) absolutely screams to 7 grand!!! Its almost completely stock, with just a 4 barrell and a set of cheapo headers and has over 400 horse and 400 ft lbs and runs 12s. This thing breaks the tires loose even rolling down the road if I nail it. I'd put it up against a stock 454 any day, any time.

http://i41.tinypic.com/2h3r09z.jpg

another thing to consider with a ls1 conversion in ca.is the emissions required would make it really hard.as it would have to be obd 2.all of the factory emissions,cats,4 heated o2 sensors,the correct trans.obd1 cars you can use any trans you want.obd2 cats can be as much as 1200$ a piece.in a smogable vehicle it is easier/cheaper to stay gen 1 or 2 sbc

I know virtually nothing about California emissions, but an argument could be made that an LS burns cleaner than an old SBC.

I know virtually nothing about California emissions, but an argument could be made that an LS burns cleaner than an old SBC.

It sounds as though you have good working knowledge of this swap. Can you provide a close cost estimate to have this swap done, turnkey? If I provide nothing but the stock 305 elky? I live outside of any metro area so no smog test.

OldCamino what does the timing box go for??:texas:

last i heard (dont know for sure) to convert to a distributer was big $$..:dontknow:
500$ just for the timing cover + dist. http://www.summitracing.com/parts/NAL-88958679/

No! The LS1 is a clean-sheet re-design of the SBC. The ports in the heads are HUGE and flow massive amounts of air/fuel. The crank to cam spacing is larger and all eight cylinder ports are replicated (identical) for consistency. My 6.0 (used; out of an Escalade) absolutely screams to 7 grand!!! Its almost completely stock, with just a 4 barrell and a set of cheapo headers and has over 400 horse and 400 ft lbs and runs 12s. This thing breaks the tires loose even rolling down the road if I nail it. I'd put it up against a stock 454 any day, any time.

http://i41.tinypic.com/2h3r09z.jpg

Man that looks good. LS1 in the future.

Ketchup & prime rib,, oh yeah baby!!!!!!!!!!!!!! On steaks as well!!!!!!!!!!!!!! Oh and scambled eggs too,,,,, now I`m hungry,,, Matty man

one of the chevy mags did a comparo between a ls and a 400 gen 1 and were both within a couple hp of each other. so without useing the efi why go through all the hassles and money.the secret is in the electronics.why step into the 21 st century then step back a decade:dontknow:

Here you go:

http://www.summitracing.com/parts/EDL-7118/........no distributor needed.

As far as cost, the lion's share of the cost will be the cost of the junkyard engine. The 4.8 and 5.3 truck engines seem to be cheaper. The 6.0 is more and the all-aluminum ones (Vette, Camaro, GTO) are pricey. I would say that BESIDES the engine you're looking at $1500 or $2000.

The price is also affected by one's ability to fab small pieces and be creative. If you have to go out and buy everything then, of course, the price gets higher.

the only issue i have with the Ls series motors is the remote oil pump. i have seem a few just kill the pump and crap a very expensive engine because of pump misalignment.

THe price difference between EFI and Carb is almost negligible and comparing what you get with each package the EFI is the way to go. Also any parts you get for a 5.3 will work on everything when going to a bigger engine (save an LS7 snouted engine)

If you do not like wiring get with a company that makes swap harnesses. They are around 150-200 more than a converted harness but so much cleaner.

one of the chevy mags did a comparo between a ls and a 400 gen 1 and were both within a couple hp of each other. so without useing the efi why go through all the hassles and money.the secret is in the electronics.why step into the 21 st century then step back a decade:dontknow:

I don't think 400 SBCs are easy to find anymore and I am certain that the LS kills a an old school SBC power-wise unless aftermarket parts (i.e. heads) are used.

A common misconception is that the "secret" is in the electronics. That is far from the truth. I have an MSD box for electronics. Do you mean fuel injection? Actually, the power difference between EFI and carbureted is negligible. There have been numerous comparos in the car mags. EFI generally has more torque and carbs tend to have more peak power but the difference is attributed to plenum design not necessarily atomization of the fuel in the incoming charge of air. EFI/carb - usually <2 or 3 hp difference.

What is the "secret" then? The secret is replicated ports with massive flow numbers, six bolts mains, rigid block with structural oil pan, and everything GM engineers have learned in 55 years.

Here is what I know: I took a junkyard LS, slapped a carb and headers on it and went to the track and ran 12.3 @ 109 in the quarter.

they actually matched the two builds very closely both carb motors. i dont remember the ign on the ls. but they were within 1 or 2 hp of each other. i am not saying the ls doesnt run really good because they do .but put the same compression and cam in a 400 and it will stay door to door with the ls. you put the electronics /efi and stand alone controller on the ls and its a whole different story. as for the 400 s hard to find ,not really i have 3 and know of 2 more within 2 blocks of the house. i ran a 12.80 in a luv truck with a 300 hp 350. 12.3 is great but injected and tuned it should be in the 11 s

Do a head swap on each with a matched cam and see who pulls ahead. The great thing about the LS motors is the way they respond. Their head flow numbers are just unmatched besides big blocks.

Also what size engine were they testing for an LS? If a 364 4.0 bore engine was used then it stayed with it even being down 36 cubes.

they actually matched the two builds very closely both carb motors. i dont remember the ign on the ls. but they were within 1 or 2 hp of each other. i am not saying the ls doesnt run really good because they do .but put the same compression and cam in a 400 and it will stay door to door with the ls. you put the electronics /efi and stand alone controller on the ls and its a whole different story. as for the 400 s hard to find ,not really i have 3 and know of 2 more within 2 blocks of the house. i ran a 12.80 in a luv truck with a 300 hp 350. 12.3 is great but injected and tuned it should be in the 11 s

Yeah those 2 bolt main 400s are awesome. And some people hit water jacket when they go to bore them out. All LS motors are 6 bolt mains BTW.

Are you reading your own post? "put some compression and cam in" - a SBC to keep up with a stock LS1. As for suggesting I need a "tune" You know nothing about me, or my car, or my engine. It runs exceptionally well and I "tuned" it when I built it. In my lifetime, I have run stock EFI, I have run Megasquirt, and I have run carbureted. If the carb is adjusted correctly, they make the same power. Fuel injection is not magic. please.

i didnt say you needed a tune ,calm down. i was refering to a good electronics tune for the efi system. at 12.3 with a stock used ls ,it is tuned great and running fine. the carbs however great they run, can never match the throttle response and consistancy of an properly set up efi system. you eliminate all of the fuel drop out of a carb ,no cylinder lean conditions.you can taylor each injector to make corrections for engine flow differances. so many things you cant do with a carb you can with a efi system. a friend of mine had the same battle with me over the 6.0 in his 66 nova. he finally tried the efi route and picked up 3 tenths in the qtr ,9 mph and 5 miles per gallon. that improvement is real hard to ignore.now his 6.0 is far from stock and now runs in the low 11 s and as for the 6 bolt mains ,big deal i have run 10 sec motors with 2 bolt mains and never broke a bolt or cap or had any bearing issues.so i guess the ls needs them to hold them together and the gen 1 and 2 dont.the 400 blocks dont hit water until over 60 thou .and i never bore past 30.both motor classes are great and have great potential,it is just a matter of choice and preferance,absolutly nothing to fight over just stating my opinion

Ls bottom ends are bullet proof from the factory I've seen a gto running 15lbs of boost for 50k miles not problem and certainly not babied you could never do that with a gen 1 motor and still use it as a daily driver without constant maintenance

No big deal, just want to communicate the superiority of the LS family of engines.

It is not so much that the main caps break, it is the longitudinal stresses on the block under high load that cause the bearings to wear prematurely. The bores can actually be twisted out-of-round slightly under exceptionally high load too.

All 400s were flat tappet, right? and as for valvetrain the LS motors have 15 degree valves, SBC were 23!

50 year old technology vs today's tech its apples and orange no comparison

It is not so much that the main caps break, it is the longitudinal stresses on the block under high load that cause the bearings to wear prematurely. The bores can actually be twisted out-of-round slightly under exceptionally high load too.


Not sure when gen 1 mains start to walk but it takes 900+ rwhp to get a LS main to walk and then a stud kit is good to whatever the block is.

we ran a 13.5 to 1 350 ,tr1y w/2 660 carbs with 300 hp lazar nitrous unit and shifted at 8500 rpm and never had any bottom end issues,we torched a couple blocks but o ringing it sloved that issue. all of the technoligy in the ls series engines is the magic behind them. i like some of the ls features so dont get me wrong.i am waiting to see where they go a little further before i fully warm up to them.you can not argue with thier performance, it is good.but even nascar is going efi.i have had my eye on the 7 litre ls for my next toy. 90 million gen 1 small blocks vs 10 million ls engines you get real comfortable knowing what it will take,and get a little gun shy jumping in with 10,000 $ to try a new engine design.

OP - If you wanted to try a junkyard engine - a running, carbed LS setup might cost you $1500

I found 4.8s (lots of 'em) on car-part.com for less than $500 the 5.3s are right around that same price.