C
Caleb
question? What is the difference between an LT1 and a LS1 firebird engine?? I know LS1 are 1998-2002 but what is the difference?
H
harocuda
A simple way to answer your question would be to just say that the LT1 is older then the LS1, but it's more complicated then that. In this case, newer is better. General Motors has been making different engine foundations for each of thier brand identity for decades. In modern times they are combining powertrain materials to save operationg costs for obvious reasons. It gets confusing because they need to keep the engines in the performance models like the corvette ahead of the curve so people still buy them instead of the cheaper Camaros and Trans-Ams. The LT1 is the second generation small block chevy engine, meaning that there are enough differences in block structure and parts to make it hard to use the same parts on older engines. Like wise, the LS1 is the Gen III small block GM engine. The newer engines seem to keep getting better by the generation as far as performance foundations for upgrades go. The LT1 was available from 1992-1997 for most of GM's line up. In 1998 the LS1 hit the market but in that year it was only available in the Corvette; all other models still used the LT1. The LS1 was only available to Trans Ams and Camaros in 1999 and newer.
There are a lot of differences in the parts for each engine family, but here are some of the biggest differences besides them being just different generation engines:
The LT1 has a unique Optispark ignition, where as the LS1 has a DIS (digital ignition system) which has a coil for each spark plug. The DIS has the advantage because it can control each cylinders timing individually.
The LT1 has 4 bolts for each main cap holding the crankshaft down which is good compared to older engines, but the LS1 has 6 bolts per main cap. The 6 bolt setup is designed differently and provides even clamping forces on the metal to reduce fatigue under critical conditions and hold the crankshaft stronger then the 4 bolt setup.
The LT1's block is made of steel, but the LS1 is made of aluminum making it lighter. Because aluminum sheds heat better then steel, it keeps the engine cool and alows you safely make more horsepower with performance upgrades.
The LT1 uses a traditional five bolt hexagonal head bolt arrangement per cylinder, but the LS1 uses only 4 per cylinder. The only reason that the LT1 would be better for a build up in this department would be if you were going to be boosting it with an enourmous amount of pressure from a big fat turbo and needed the extra bolt strength to minimize head lifting, but this alone does not make it worth the fight over the LS1.
The LT1's firing order is 1-8-4-3-6-5-7-2, but the LS1's is 1-8-7-2-6-5-4-3 to follow other modern V8 firing order patterns. (dumb, i know).
The LT1 and LS1 are both 5.7 liter engines, but the way they get thier sizes are different. The LT1 has a cylinder bore of 4.40" and a crankshaft stroke of 3.48" and the LS1 has a narrower 3.90" cylinder bore but a longer 3.62" stroke.
Those are just some to scratch the surface for ya. Either way, the LS1 makes a better candidate for a performance engine if you take the performance level way up there. There are more parts aftermarket parts available for it then the LT1, which gives it a huge advantage, but it might also be harder to get your hands on one considering they are not as available in junkyards as the older LT1. Hope this helps, sorry so long!
There are a lot of differences in the parts for each engine family, but here are some of the biggest differences besides them being just different generation engines:
The LT1 has a unique Optispark ignition, where as the LS1 has a DIS (digital ignition system) which has a coil for each spark plug. The DIS has the advantage because it can control each cylinders timing individually.
The LT1 has 4 bolts for each main cap holding the crankshaft down which is good compared to older engines, but the LS1 has 6 bolts per main cap. The 6 bolt setup is designed differently and provides even clamping forces on the metal to reduce fatigue under critical conditions and hold the crankshaft stronger then the 4 bolt setup.
The LT1's block is made of steel, but the LS1 is made of aluminum making it lighter. Because aluminum sheds heat better then steel, it keeps the engine cool and alows you safely make more horsepower with performance upgrades.
The LT1 uses a traditional five bolt hexagonal head bolt arrangement per cylinder, but the LS1 uses only 4 per cylinder. The only reason that the LT1 would be better for a build up in this department would be if you were going to be boosting it with an enourmous amount of pressure from a big fat turbo and needed the extra bolt strength to minimize head lifting, but this alone does not make it worth the fight over the LS1.
The LT1's firing order is 1-8-4-3-6-5-7-2, but the LS1's is 1-8-7-2-6-5-4-3 to follow other modern V8 firing order patterns. (dumb, i know).
The LT1 and LS1 are both 5.7 liter engines, but the way they get thier sizes are different. The LT1 has a cylinder bore of 4.40" and a crankshaft stroke of 3.48" and the LS1 has a narrower 3.90" cylinder bore but a longer 3.62" stroke.
Those are just some to scratch the surface for ya. Either way, the LS1 makes a better candidate for a performance engine if you take the performance level way up there. There are more parts aftermarket parts available for it then the LT1, which gives it a huge advantage, but it might also be harder to get your hands on one considering they are not as available in junkyards as the older LT1. Hope this helps, sorry so long!
B
backoff
LT1 has better deep tone to it here is a website with thirdgens.
www.thirdgen.org
www.thirdgen.org
C
camaro
I believe that the LT1 was designed to be put into camaros and the LS1 was put in the corvettes. I know for a fact that LT1 engines were put in the camaros within the same years of your firebird. They are both F body cars with basically the same structure so the LT1 should go in no problem. CHevy always wanted to keep the corvette the top in model line in performance so the engine would always have to have more power than the camaro which would make for the difference in engine. The corvette engine would have more power which I believe is the LS.
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J
johnboy
The 5.7 LT1 is an Iron block with alluminum heads. Duraspark ignition that makes 285 - 300 HP
LS1 is all aluminum with cast sleeves and coil for plug ignition make, 320-345hp
LS1 is all aluminum with cast sleeves and coil for plug ignition make, 320-345hp
D
Don B
Q: Does the LS1 use reverse-flow cooling like the LT1 did?
A: No. GM Went back to the standard cooling configuration for the LS1. The LT1 cools the heads first while the LS1 cools the heads last. Each system has their advantages and disadvantages. With reverse cooling there is the risk of hot-spots on the cylinder walls. Because of this care should be taken whenever any type of cooling system maintenance is done on an LT1 engine.
A: No. GM Went back to the standard cooling configuration for the LS1. The LT1 cools the heads first while the LS1 cools the heads last. Each system has their advantages and disadvantages. With reverse cooling there is the risk of hot-spots on the cylinder walls. Because of this care should be taken whenever any type of cooling system maintenance is done on an LT1 engine.
F
Firebird
I was just going to say they were completely different. The cubic inches are the same, but all the pieces parts are different. The LS1 was designed starting with a clean sheet of paper.
Now, the practical differences are important, and those have already been covered.
Now, the practical differences are important, and those have already been covered.
carguy_z28
New member
Responding to the long post on this thread, The LT1 was used from 1993-1997, not 1992... And the LS1 was put in the TA and Z28 from 1998-2002 not 1999... LT1 had 275 HP untill 1997 when the anniversary came out and was ratted at 330 HP, Exept for the SS camaro and the WS6 TA which was rated at 305 HP The LS1 was rated at 320 HP pretty much all the way through. The main difference between the Z28/TA and Vette, was the Cam, And as previously stated in another post, the Camaro /TA actually had a wilder cam and put more power to the ground, the TA weighed in at 400LBS heavier than the Vette, and was .03 seconds slower in the 0-60 runs. My dyno run shows my 2001 stock Vette convert at 293 HP to the wheels and my Dads 02 TA convert at 297 Hp at the wheels before his mods.
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