How Does Lt4 Compare To Lt1 Engine
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Le Mans Master
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From: Saraland Alabama
St. Jude Donor '11-'12-'13-'14-'15-'16
How Does Lt4 Compare To Lt1 Engine
The LT4 was the super engine of the 96 model year and then in 97 the LS1 was introduced. How do they compare? I know the LT4 had roller rockers but that is about the extent of my knowledge about LT4 and I know even less about the LS1.
Melting Slicks
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From: Wichita KS
Originally Posted by FLACHUSNRET
The LT4 was the super engine of the 96 model year and then in 97 the LS1 was introduced. How do they compare? I know the LT4 had roller rockers but that is about the extent of my knowledge about LT4 and I know even less about the LS1.
A little on the LS1.
http://www.idavette.net/hib/ls1c.html
Drifting
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Originally Posted by FLACHUSNRET
The LT4 was the super engine of the 96 model year and then in 97 the LS1 was introduced. How do they compare? I know the LT4 had roller rockers but that is about the extent of my knowledge about LT4 and I know even less about the LS1.
Race Director
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by smokeyburnouts
performance-wise the LT4s were underrated, big time. expect a LT4 vette to be a tad faster than a LS1 stock for stock.
Leave your LT-4's pink slip at home, brother.
By the way, which engine are you asking about; LT-1 or LS1??
Larry
code5coupe
PS I haven't noticed many LT-4 owners actually saying that the LT-4 is faster than a C5.... ??
Last edited by rocco16; Jul 17, 2004 at 05:47 PM.
Burning Brakes
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From: Pittsburgh PA
"The performance figures and specifications listed below were compiled by Forum Member, Stan A (Stan Adelman) of Auto Performance Test Lab located in Atlanta, Georgia. The Corvette Action Center would like to thank Stan for allowing us to post his Performance Review Data here.
Regarding the stock LT4 horsepower numbers, Stan explains:
The LT4 really can vary in Horsepower and torque. Like I said, the average one on the street comes in between 350hp to 360hp. We have tested over 125 LT4 units since 1996 and found that less than 25% of the units come in under 345hp. About 15% come in between 360hp and 375hp. About 10% range between 375hp and 385hp. 2% have been found to hit the very low 390hp range. This is all stock from Bowling Green. Keep in mind that the torque also increases too. One unit came in on the dyno at 392hp/426lbs-ft torque @5850rpm. Very rare but still present out there. This is why there have been reports of LT4s running with or past ZR1-LT5 cars over the years. Basically, the LT4 will out run the LS1 in 75% of all cases."
by the way, i dont have a LT4
Regarding the stock LT4 horsepower numbers, Stan explains:
The LT4 really can vary in Horsepower and torque. Like I said, the average one on the street comes in between 350hp to 360hp. We have tested over 125 LT4 units since 1996 and found that less than 25% of the units come in under 345hp. About 15% come in between 360hp and 375hp. About 10% range between 375hp and 385hp. 2% have been found to hit the very low 390hp range. This is all stock from Bowling Green. Keep in mind that the torque also increases too. One unit came in on the dyno at 392hp/426lbs-ft torque @5850rpm. Very rare but still present out there. This is why there have been reports of LT4s running with or past ZR1-LT5 cars over the years. Basically, the LT4 will out run the LS1 in 75% of all cases."
by the way, i dont have a LT4
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Melting Slicks
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From: Pomfret, CT
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Originally Posted by rocco16
Huh-uh. Even if the LT-4 is underrated, it still doesn't put out the peak horsepower of the LS1. Plus the C5 is a few pounds lighter than the '96 C4.
Leave your LT-4's pink slip at home, brother.
To address the original question; there are many, many parts in the LT-4 engine that are different from the LT-1. These parts add up to power in the rpm range above where the LT-1 runs out of breath.
Larry
code5coupe
PS I haven't noticed many LT-4 owners actually saying that the LT-4 is faster than a C5.... ??
Leave your LT-4's pink slip at home, brother.
To address the original question; there are many, many parts in the LT-4 engine that are different from the LT-1. These parts add up to power in the rpm range above where the LT-1 runs out of breath.
Larry
code5coupe
PS I haven't noticed many LT-4 owners actually saying that the LT-4 is faster than a C5.... ??
Stock for stock....it all boils down to the driver. They are all fairly close to one another, especially when you are talking about stick cars. I'll bring my pink slip and my LT1! 
-Rick
Melting Slicks
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From: n/a SC
"These parts add up to power in the rpm range above where the LT-1 runs out of breath."
I think you're talking about a l98 the lt1 doesn't run "out of breath" it pulls hard all the way to 6 grand.
I think you're talking about a l98 the lt1 doesn't run "out of breath" it pulls hard all the way to 6 grand.
Melting Slicks
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From: Construction Sucks! MI
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St. Jude Contributor '03 & '05
Differences between the LT1 and LT4
LT1 vs. LT4
LT4 was under-rated by GM due to the LS1 motor coming out.
Here are the specs of the LS1 (LS6 included as a bonus )
LS1 vs. LS6
If you had equal drivers and stock for stock, I would bet LT4, LS1, LT1
LT1 vs. LT4
LT4 was under-rated by GM due to the LS1 motor coming out.
Here are the specs of the LS1 (LS6 included as a bonus
)LS1 vs. LS6
If you had equal drivers and stock for stock, I would bet LT4, LS1, LT1
Team Owner
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From: Athens AL
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The LT4 was underrated due to the impending introduction of the LS1 C5. It actually puts out ~300rwhp, which gives it about ~350 crank hp, and yet it was rated at 330chp.
An early LS1 will lose to an LT4 at the track, given equal driver capability, more often than not. LS6's and later LS1's will beat the LT4.
LS1 is an entirely different engine, Aluminum block, huge heads, no components interchange with the LTs to my knowledge. Different ignition setup too, LS1 has a coil for each cylinder. LT4 has the Optispark ignition.
LT1/4 differences are mainly cam, heads, intake manifold. There are some small internal changes, but they arent all that important.
An early LS1 will lose to an LT4 at the track, given equal driver capability, more often than not. LS6's and later LS1's will beat the LT4.
LS1 is an entirely different engine, Aluminum block, huge heads, no components interchange with the LTs to my knowledge. Different ignition setup too, LS1 has a coil for each cylinder. LT4 has the Optispark ignition.
LT1/4 differences are mainly cam, heads, intake manifold. There are some small internal changes, but they arent all that important.
Race Director
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by wildman378
I think you're talking about a l98 the lt1 doesn't run "out of breath" it pulls hard all the way to 6 grand.
Not that it matters much.
Larry
code5coupe
