1gary

Now that the LT-LS has been around for awhile and have aftermarket parts,do they cost more to build than the Gen I's??.

Jim85IROC

iTrader: (2)

Not if you compare apples to apples. 600hp costs roughly the same in either case. The big difference is that there aren't any cheap cast parts available for ls motors, but then again, there's no real reason for them. A stock lq4 is stronger and more powerful than a mild sbc.

1gary

Yeah Jim.The point about hp vs costs is well taken.I don't remember where I saw LS aftermarket head pricing.I mean it wasn't what I was looking for and I just looked quick at it.But I could be wrong,I thought they where expensive.

Kevin91Z

iTrader: (1)

Heads, camshafts, and headers are more expensive for LS1 parts than SBC parts, per Jegs or Summit Racing's online catalogs for new parts. For used parts, its wide open. But you also have to factor in the cost of modifying an LSx engine to fit in the thirdgen engine bay, as the motor mounts and k-member are different, and changing the entire dash to the 4th gen gauges because the thirdgen gauges are not compatible. In the end, only you can tell if its worth it, beacuse its your car.

Guest

Cost to put a lt1 in a thirdgen is far less than an lsx, so I'd say that is the cheaper route. You start looking at full custom K-Member replacements and other stuff when going to an lsx which gets expensive fast.

Including the stage 2 T56, it probably costs me around $4,000 for the entire swap with a cam and springs.

keeslinger31

Its really a crapshoot they all have potential. I like lt1's the most. Seems to be the odd child out as its a hybrid of the two. And the intake is sexy.

Jim85IROC

iTrader: (2)

If you do an apples to apples comparison, most of it kind of washes out. Most aftermarket heads cost more for an LS, but for most horsepower needs, stock LS heads or mildly ported stock heads will do the job, whereas with an SBC you have to buy aftermarket heads no matter what. Try to find a set of 330cfm SBC heads for $350/each like you can get with stock LS3 heads.

Custom cam grinds are $400 regardless of what motor you put them in, but I agree that off the shelf SBC cams are cheaper.

Headers are a tough comparison to make because the prices are generally based on the chassis, but LS headers for an old chassis are a niche item, so yeah, it's hard to argue that they're more expensive. But, what's a good set of 1 7/8 stainless SBC longtubes go for these days? If you can find any, they're probably closely priced. The difference is that there's no cheap painted steel 1 5/8" stuff out there for LS motors because they're inadequate.

Rotating assembly prices equal out when you start talking about fully forged stuff with ARP fasteners. Like with the heads, there isn't any "cheap" stuff for LS applications because it would be inferior to the stock stuff.

Intake/induction/fueling/timing/etc type of stuff is hard to compare. Again, the stock LS stuff is adequate to support fairly high horsepower levels. SBC stuff isn't, so you need to start looking into upgrading intakes, injectors, etc. A lot of this is going to offset any cost savings gained from cheaper cams & headers until you start getting up to horsepower levels that require big upgrades to the stock LS stuff.

There's no doubt that you need to pay to play with LS stuff, but to make an SBC perform at similar levels (excluding driveability & fuel economy issues), the cost differential seems to be small.

mille_3

iTrader: (3)

Gauges are not compatible with an LSX? I must be misunderstanding what you are trying to say.........

Orr89RocZ

iTrader: (20)

I dont think the 80's gauges can be controlled by the electrical signals from the LS pcm. So you'd have to swap out.

Yep, my 330+ cfm heads for sbc run about 3000 when its all said and done. Billet cams will cost closer to 400 but you can get regular core cams that are custom spec'd for under 350. LS cams can be more but I'm not sure what cores they use. Most probably are billet but depends. Plus they are larger cams to begin with so more material is more cost.

If you could do a LS3 headed Lq4/Lq9 junk yard motor with decent cam, theres no reason why you cant have 450-500whp. Thats pretty darn impressive. And thats pretty cheap / good bang for the buck so to speak

But if you were going to build things up apples to apples starting with fresh bottom end, forged components, the prices start to even out but sbc cranks can be had for abit cheaper than lsx stuff from quick browsing around. 650-700 bucks will get you a nice forged sbc crank but lsx seems like 1000.

LS aftermarket heads are good money, 2000-2500 and some even more. But you really dont need to go that direction as factory castings are pretty good and alot of companies have great cnc profiles for under 1500 bucks for machine work to bring your factory castings up to race spec. 300+ cfm can make mid high 400's whp on 346" ls1 with decent cam and still be driveable. SBC to match that will take alot more RPM or alot more cubes and good aftermarket heads. Cost would start to add up there.

The under 550hp stuff, lsx clearly has advantage. 600+ it starts to get interesting on pricing. Its hard for a sbc 23 deg head to compete with 11-15 deg heads but if you do your homework, you can still hang with lsx. You can have 700+ hp pump gas sbc's under 434 inches. 700 hp 427 LS motor is no easy task either so the costs are getting closer.

LT motors are basically same as sbc underneath the heads. Advantage LT1 is you can do 3 things: 1) stock heads can support 350whp fairly easily with a big cam...or you can send them to port for under 1500 and make great power that rivals most aftermarket heads in similar class, and LT1 heads because of reverse cooling arent cheap. They are much more money than sbc heads and almost same as LS heads for some reason.
2) LT1 intake is pretty good out the box. Short runner design builds high rpm power and flat torque curves. Port work for even high rpm/hp builds. 400-450whp is doable. No need for intake mods which saves alot compared to a TPI car....
3) reverse cooling allows for higher compression. I've seen 12 to 1 on the street. This can make serious power advantage over sbc.

So even tho aftermarket heads are expensive its not needed. LT motors to a certain hp level are better than sbc in my opinion minus the 7K rpm limit in PCM and optispark. I would say under 575hp or so. LT is limited in cubes tho, hard to get stock block much over 396"s. SBC has aftermarket blocks and not to mention 15-18 deg heads you COULD use to make alot of power.

92purplehaze

iTrader: (8)

Lol a tpi guy trolling the swap boards

mille_3

iTrader: (3)

Yes they can. That's why I was asking Jim85 if I misunderstood what he was saying.

Copperhead

I had an LS6 with some aftermarket goodies on hand needing rebuild, and decided that going with a TPI 383 would be the difference between getting it running this summer, and not. What with crossmember mods, swap headers, swap mounts, and swapping out the entire harness, I decided it would take me friggin ages to get it done. Whereas, to go SBC, all I had to do was drop it in and wire it up since it was TPI car to start with. I`m only looking for 400-450 fwhp so it made more sense for me.

Cashwise to build the engine itself it may or may not be a wash (see all the above) but if you`re paying someone else to do the swap the LS is going to stomp your wallet a lot harder than the SBC. LS versions of the T56 are also harder to come by and more $$ than LT versions.

Driveability? Well, we`ll see, but mine is really only a roadrace car so won`t matter a whole lot to me. The nastier the better!

Orr89RocZ

iTrader: (20)

Oh well thats good news. Didnt know for certain how that would work. Does it depend on year thirdgen tho? Pontiac digital dash vs camaro dash?

five7kid

iTrader: (14)

In a fully emissions-compatible swap, the fuel level sender data has to go to the PCM because that information is part of the emissions control decision process. The PCM fuel gauge serial output signal is not compatible with 3rd gen gauges. So, that drives you to a 4th gen cluster swap in states like California with strict emissions inspection and testing.

But, I didn't interpret the original question as an engine swap into a 3rd gen question, but an engine build question. Perhaps I am interpreting it too narrowly. Regardless, the LQ4/9 w/L92 heads example makes an important point - you don't have to spend $2k on heads to get 500 HP.

To take that further, I haven't had to even do a head swap to get my LS1/4L60E car to the 12.0's in the 1/4 mile, and still drive it to work daily. I had planned on a Vortec head/cam upgrade in the car before this LS1 fell out into my lap, but had I gone that route, I doubt it would have run as quick, and I'm confident it would not have been as commuter-friendly. Did I spend more to do the LS1/4L60E swap? Yes. But, I think I've been repaid already.

Jim85IROC

iTrader: (2)

? I didn't say anything about gauges.

Orr89RocZ

iTrader: (20)

I got a 4th gen tank and fuel bucket assembly in my car and all you need to do is change sending unit in the tank to the right ohms to work with the 3rd gen dash gauge. However if the fuel level signal has to go into the ecm for whatever reason then it may not accept the altered signal and not sure if you can program that out. I know the evap system is on the gas tank and wires go to ecm and i think it may use fuel level for some functions but not sure. For emissions that would be a concern

Copperhead

None of this is a problem or an expense if you go Hi-Po TPI

five7kid

iTrader: (14)

The point being that it will cost as much to go Hi-Po TPI as an LS1 swap. Complete donor LS1 car, take what you need for the full swap into the 3rd gen, part out the rest, and the cost will be about the same as getting a TPI to the same power level.

But, that wasn't the point of the thread (if I'm interpreting it correctly).

dabird07

iTrader: (10)

1. pORTED HEADS
2. POLISHED INTAKE (ASLONG WITH HEADS)
3. 3 - ANGLE VALVE JOB

mille_3

iTrader: (3)

I meant Kevin91Z....sorry

86White_T/A305

This is hard to judge..its subjective to your goal of the motor to begin with.If we are talking strictly cost of motor build..not swap costs then I would say the lt/ls motors can be cheaper.if you are going carbed vs injected on any of them is also a factor to consider.

To get 400whp with a lsx can be as simple as a cam and spring swap all else being stock
An lt1 will be cam and head work and smaller supporting mods for safety.
A sbc is going to be cam/aftermarket heads etc etc

My 383 hsr/700r4 that was making 360whp/380wtq.It was afr heads,1.7 rockers,280xfi cam,bosch3 injectors,hooker headers.Cost about $5000 build

My current lq4 making almost the same power with just a small cam on stock exhaust.Cam kit with rods and new springs cost $699,new wires cost me $250.I have less than 2grand in the motor

The potential to grow with the lt/ls makes them more favorable while still using modified stock parts where as the sbc needs to be beefed up from top to bottom.

I next major $$ is if you are building the motor yourself vs paying a shop labor rates.i did my cam swap myself on my lq4 which took about 1.5 hrs.My 383 build cost me over a grand on just labor/machining.

I dont think its fair to try to compare these builds apples to apples with too many factors that can and will sway the scale depending how you look at it.Build what you like at the best bargain you can and build it right..hopefully your happy with the results end of the day.

Z28FAST1

Apparently it takes $6-7 to build a TPI that puts down 360+rwhp (H/C/ ported plenum and intake). However, there are no stock cube TPI's making over 400rwhp (only potential )

The are a handful of bigger cube TPI's that are making 400-420 rwhp but you better have $$$$$ to fund these max effort builds.

I agree with the statement about the potential to grow, just look at ls1tech with several max effort LS1's making 500+rwhp and stock 5.3's with turbo's running 9's!!!!

Depends on everyone's goal.

DIGGLER

iTrader: (1)

the LT1 in my gta is a freshened up shortblock with a ported set of stock heads, and a cam. made 425 through a th400, 9", and 28" slicks. went low 9's with some nitrous.

86White_T/A305

Im only talkin about motor build cost..not what it takes to swap in anything else into a thirdgen.That wasnt part of the OP's original question from my understanding.

Everything has its pros and cons and depends on its intended use where any motor can be cheap or expensive to build.350 sbc can be had for pennies on the dollar.. an lq4/9 can be had for a few hundred bucks depending where you find it.5.3s are everywhere and even cheaper.

Personally you have to ask yourself..do you really want to take the cheapest build parts in the first place to save a buck and have a motor that you cant rely on regardless what platform you choose.I hope not,build what you have,build it right and enjoy it for what you design the motor to do.Build cost depend on you more than anything.

Orr89RocZ

iTrader: (20)

Its already been said if you arent pushing big numbers then lsx may be cheaper. Its built pretty strong fron factory and has good intake/heads stock. 400-450 whp is not big numbers. If you were doin 700+ crank its gonna be pretty similar