Please close mods

[Bowtieheart]

Ok so I recently picked up this 84 Cutlass and want to do an Ls swap. Started researching this swap about a month ago and there's a lot of threads with good info but of course, we always want more🙂
That being said, while researching the swap for more straight forward answers, I stumbled across people doing the Lt swaps in their G-Bodies and so that started a new portal. Lol. I Went on youtube and was pretty impressed by the power of the Lt1. So my question is, I know stock for stock, the Ls1 dominates but it also comes at the price of a pretty penny. The Lt1, while stock is no slouch, and for a few bucks, can be just a respectable as the Ls1.
So which is more cost effective for a mid 12's street/streetable car? No turbo/nitrous/supercharger.

 

[Kansas Bu Wagon]

Re: Lt1 vs Ls1 cost and power (In details)

You can send your stock lt1 heads here and get around 400 hp and tq depending in the cam you choose.

And cost just depends on how much work you can do yourself. The price will vary a lot if you can or can't do the wiring harness yourself. And all the other variables. Lol

 

[lilbowtie]

Re: Lt1 vs Ls1 cost and power (In details)

Take a look at a stock 1970 Lt1 - 370 HP which can net you 12.0 time slips.

 

[pencero]

Re: Lt1 vs Ls1 cost and power (In details)

I don't have specific details but I'd recommend the newer fake 'LT1' if you want your car to be 'streetable'. The older LT1 is such a monstrous engine it can't get 15mpg on it's best day and it's definitely for the strip. It delivers so much torque that it's dangerous in ambiguous situations. The newer LT1's in the Impala ss / fleetwood / Roadmaster / f-bodies etc. can deliver 22mpg on the highway NP, and thats a big deal / big difference for how 'streetable' your Cutlass will be overall. It's very smooth engine, and delivers the same punch everytime so you never get carried away fishtailing except for those times you're doing it by choice. It may make only 300 hp stock, but with just a few upgrades and a chip 400 is not very far away , and you should be able to keep highway mpg near 20 even with a chip. The oldschool LT1 is fantastic, but unless you're wallet is huge it will limit your range so broadly b/c of how much gas it wastes. If you drive the Cutlass on a regular basis, you will also probably find yourself with a drawer full of speeding tickets. When I drove my friends mc with an LT1 around the block, it hit 55mph in less than a city block but I'd have swore it felt like I was going 20mph

 

[Bowtieheart]

Re: Lt1 vs Ls1 cost and power (In details)

Thats's true, I failed to mention I'd be doing most, if not all the work myself. The only part of the swap honestly seems a little intimidating is the wiring but i'm sure with a couple diagrams and help from you guys, I believe I can get'er done.

For the Lt1, this is pretty much the stuff needed correct?
As far as mounts, to my understanding, I can reuse the stock Sbc mounts but not the Olds mounts from my 307. $50? plus Poly bushings
As far as headers, I can use any longtubes from a Sbc with little to no mods. $400?
Trans crossmember- Not really sure. $175
Wireing-$500

Ls1 stuff
Motor mounts-BRP(pricey but prob the best one out that I keep hearing) I just know for sure to avoid Transdapt. $479
Hummer oil pan- $249
Painless harness(if it's a lot more involved than the Lt1) Around $500
Headers-Brp/Hammered Hookers-$800

So price wise and based on my goals, would it be safe to say i'd be better off going the Lt1 route? I also plan on getting the swap refereed by the state, so it can be a legal swap.

 

[maven]

Re: Lt1 vs Ls1 cost and power (In details)

Also dont forget to compare apples to apples...the LT1 from the B/D bodies(big cars) doesnt have aluminum heads....these may be cheaper but they arent the LT1 most people really talk about when they talk about GenII motors. They may be cheaper but they are heavier and have less hp to start. The 5.3's are also an excellent choice, theres many many more of those out there than there are LS1s. And they are MUCH cheaper. $500 gets you a 5.3 all day by me. An LS1 is $1800+. And both iron and alloy LT1s are like hens teeth in the JY compared to the Gen3 truck engines.

Mount plates are $50 from multiple sources on Ebay. CutThroat4x4 has ones that are dual drilled for both stock LS1 position and stock SBC position(aka 1" setback)
Pacesetter F body LS1 headers are more like $275.

Theres no appreciable difference in the quantity of or difficulty level in wiring between a Gen2 swap and a Gen3 swap.

This is the type of thing that starts wars, but I feel that a Gen3 engine is the less expensive route to 12's. (as Compared to a Gen2)

 

[Clone TIE Pilot]

Re: Lt1 vs Ls1 cost and power (In details)

I have heard that OBD1 is alot easier to reprogram/hack than OBD2. Also most LS motors are drive by wire so you have to factor that in. IMO I would not want DBW in my G body. LS1s and early LS2s I think were still had throttle cables. Of course LT1s have the optispark that may need to be taken cared of. LS probably has a larger aftermarket support now since such a swap needs alot of expensive stuff they can sell to you. Of course Olds V8s have 8 degree valve angles which are even better than the LS's 15 degree. The best angles are between 7 to 14 degrees.

 

[Bowtieheart]

Re: Lt1 vs Ls1 cost and power (In details)

$500 gets you a 5.3 all day by me. An LS1 is $1800+. And both iron and alloy LT1s are like hens teeth in the JY compared to the Gen3 truck engines.

Mount plates are $50 from multiple sources on Ebay. CutThroat4x4 has ones that are dual drilled for both stock LS1 position and stock SBC position(aka 1" setback)
Pacesetter F body LS1 headers are more like $275.


No way, wow, how well do these Cutthroat4x4 mounts actually work? And are they like BRP where you can only use one header? If they have worked good for you guys, i'll probably play it safe and get the one that has 3 mounting options. And $500 for a 5.3? Where are you located?

 

[DRIVEN]

Re: Lt1 vs Ls1 cost and power (In details)

"...cost effective for a mid 12's street/streetable car? No turbo/nitrous/supercharger."
That's a pretty tall order for either engine.

The LS has more potential and aftermarket support. The LT1 is a short production run orphan. That being said, I've done several LT1 swaps in various vehicles. Stock LT1s run great and are a relatively easy install since Gbodys came with a SBC from the factory. All the motor mounts and exhaust will work. I've never personally had a single problem with an Optispark unit. Most of the problems I've seen are a result of moisture intrusion from leaking water pumps. The '94-'95 ECM is preferred by many tuners. The aftermarket harnesses are kinda spendy make make for a much quicker installation -- especially if you aren't really comfortable with wiring. I've modified stock harnesses and it takes me about 8-10 hours to do it to my satisfaction. A cam upgrade and appropriate ECM tune (there is no "chip") would make a noticeable increase in power but probably won't get you in to the mid 12s. BTW, those "heavy" iron heads used in the B & D bodys actually flow better than the aluminum heads used in the Fbodys and Corvettes. Since the LT1 only came with a 4L60E as an automatic option, you'll need to shorten the driveline and get another crossmember if you want to keep it. But, since it's electronically controlled, your tuner can alter shift points and firmness -- which is a nice bonus. If you car already has a 200-4R in it, I'd keep it because it has closer gear spreads. Might be a good idea to have it beefed up though. You'll need the appropriate TV cable hardware too. Both transmissions are fine. I just prefer the 200-4R. Plan on upgrading the rearend to either a 3.42 or 3.73 ratio.

 

[Bowtieheart]

Re: Lt1 vs Ls1 cost and power (In details)

So Driven, if you were in my shoes, what would you do and why?