Lsx wt vs sbc weight

[alnoe]

What is the weight difference between a fully dressed aluminum head, factory iron block sbc and an aluminum ls2? I have been looking all over for concrete, actual answers and could only find a hot rod article that showed about 30 lbs. seems way too low. Anyone have actual weights?

Thanks
al noe

[chuckd71]

From other sites -
My LS3 complete except for headers, flywheel, Pressure Plate and clutch disk, ignition coils, MAF, VCM, alternator oil and water = 357 lbs

Cast iron sbc-575
w/aluminum heads-525

[jlcustomz]

When I swapped my 83 el camino froma tpi gen1 engine to ls1, it was enough weight difference to give me a poor man's cadillac stance. I think I remember reading it was near 100 pounds dressed engine to dressed engine.

[RSX302]

What is the weight difference between a fully dressed aluminum head, factory iron block sbc and an aluminum ls2? I have been looking all over for concrete, actual answers and could only find a hot rod article that showed about 30 lbs. seems way too low. Anyone have actual weights?

Thanks
al noe

Per GM,
19244097
LS3 = 415lbs (LS1 = 409lbs)

19201330
ZZ4 = 511lbs

http://www.chevroletperformance.com/_res/pdf/2011CrateEnginePreview.pdf

[barraza]

It is not as much as many people would like to believe.

For all practical purposes, the only engine differences are the aluminum block (when used in a lsx) vs iron, and the plastic intake vs aluminum. An ecu and harness don't weigh much, but it all adds up. A bare gen 1 small block weighs between 160-180 lbs depending on who you believe. A LSX iron race block weighs 225 lbs. An aluminum ls1,2,3,6 is about 125lbs, a ls7 weighs a bit more. A plastic ls intake is a little less than an aluminum old intake.

The reality is that there is probably 60-75lbs difference between an aluminum block ls3 and a gen 1 small block with aluminum heads and intake, when they are ready to run, ie including everything. A iron block ls isn't enough difference to worry about, in fact many sources put an iron ls block at about 195 lbs, which is MORE than a gen 1 bare block. There is no way the 125-150 lbs differences you hear tossed around are reality, you just dont get the strength necessary to hold the power of a ls engine with super-light structure.

Any comparisons that don't have comparably equipped engines are just pushing an agenda, such as a ls3 vs an iron headed gen 1 engine.

[alnoe]

Thanks guys. I have also looked at the gmpp data, but the two engines may be crated differently, flywheel included or not, etc. I am going to do the swap and will weigh the car before and after, just so I know. If you have any more info, let me know. Thanks

[Mkelcy]

It is not as much as many people would like to believe.

For all practical purposes, the only engine differences are the aluminum block (when used in a lsx) vs iron, and the plastic intake vs aluminum. An ecu and harness don't weigh much, but it all adds up. A bare gen 1 small block weighs between 160-180 lbs depending on who you believe. A LSX iron race block weighs 225 lbs. An aluminum ls1,2,3,6 is about 125lbs, a ls7 weighs a bit more. A plastic ls intake is a little less than an aluminum old intake.

The reality is that there is probably 60-75lbs difference between an aluminum block ls3 and a gen 1 small block with aluminum heads and intake, when they are ready to run, ie including everything. A iron block ls isn't enough difference to worry about, in fact many sources put an iron ls block at about 195 lbs, which is MORE than a gen 1 bare block. There is no way the 125-150 lbs differences you hear tossed around are reality, you just dont get the strength necessary to hold the power of a ls engine with super-light structure.

Any comparisons that don't have comparably equipped engines are just pushing an agenda, such as a ls3 vs an iron headed gen 1 engine.

Talk about agendas, the bare LS1 block starts off being 88 pounds lighter than an SBC block (http://www.hotrod.com/howto/113_0504_chevy_ls1_engine_basics/viewall.html). Subtract the composite manifold versus an aluminum manifold, subtract the mechanical fuel pump versus the electric pump in the rear of the car, add in the ECU and harness versus a carb - at worst - a wash, probably worth a few pounds in the LSx favor.

If anyone wants to tell me 100 pounds, I'll readily believe him. Oh, and the LSx engine will run rings around any comparably streetable SBC.

[Vegas69]

I agree Mike, comparing a small block to an LS is like comparing a race horse to a clydesdale.