LT1 Torque vs LS1 Torque

[EquatorHeat00]

Does this mean LS1's can't spin there wheels at the start as easily? I would think it wouldn't feel as tourquish with the extended rpm range.

325 at 2400 rpm's LT1
335 at 4500 rpm's LS1

[94 formula]

LS1's definetly still spin them I've just noticed it happens a little easier around 4000 rpms. IMHO a LT1 has more SOTP power and feels like its faster but in reality once a LS1 gets into the revs it pulls away pretty quick. I'm speaking stock for stock.

[Jay 02 TA ws6]

Hahahaha... we can spin our wheels PLENTY easily enough

[raroZ28]

Hahahaha... we can spin our wheels PLENTY easily enough

Yeah, seriously. I wonder how that whole LT1 has more low end torque than LS1 thing got started. I mean, it certainly doesn't feel like my car is faster at any point over an LS1. Don't know though. I would say they both feel the same, and we know the LS1 is faster, so.... Where do people get off sayin' that stuff? Does it have more low end?

[Jay 02 TA ws6]

The torque comes on a little sooner in the LT1, so it gives the sensation of going faster, sooner... but it's a relatively small difference, and as early as 2500-3000 RPMs, the LS1 starts making more torque than the LT1.

[94 formula]

Yeah, seriously. I wonder how that whole LT1 has more low end torque than LS1 thing got started.I mean, it certainly doesn't feel like my car is faster at any point over an LS1.Don't know though. I would say they both feel the same, and we know the LS1 is faster, so.... Where do people get off sayin' that stuff? Does it have more low end?

Like equatorheat00 stated the LT1 makes 325 at 2,400 and the LS1 makes ten more ft lbs but at over 2000 more rpms. Its all an opinion but just driving around on the street the LT1 feels like it makes more power mainly because at 2000 rpms it is making more power than an LS1. I'm not saying that an LT1 is faster in any way but it is making more power down low. When my car was stock I could stick right with my brothers 99 Z28 through 2nd after that it was lights out. The LS1 is superior but the LT1 does make more power in the lower rpms I'm sure someone on here could post dyno sheets to proove this.

[Jay 02 TA ws6]

Like equatorheat00 stated the LT1 makes 325 at 2,400 and the LS1 makes ten more ft lbs but at over 2000 more rpms. Its all an opinion but just driving around on the street the LT1 feels like it makes more power mainly because at 2000 rpms it is making more power than an LS1. I'm not saying that an LT1 is faster in any way but it is making more power down low. When my car was stock I could stick right with my brothers 99 Z28 through 2nd after that it was lights out. The LS1 is superior but the LT1 does make more power in the lower rpms I'm sure someone on here could post dyno sheets to proove this.

You're comparing peak to peak there, and yes, the LS1's peak is 2,000 RPMs higher, but it begins to make as much torque somewhere in the range of 2500-3000 RPMs...

[Jay 02 TA ws6]

Also... the LS1 really makes somewhere more in the range of 360 ft-lbs of torque stock, not 335.

I don't know how much the LT1 makes in reality... is it as underrated as the LS1 is?

[94 formula]

On ws6.com is appears peak torque is around 310 at the rear wheels stock so yeah it should be over 325 at the crank.

[Rob]

You could also go further back and say a TPI car has more low end torque than both the LT1 and LS1.

My 96 WS6 made 274/305 to the wheels when it was stock. Haven't dynoed the GTO but others have and its usually 300/320 to the wheels. There really isn't much difference to the graphs if you laid each over one another. The LT1 torque curve is very flat. The LS1 makes just as much but rises and falls, peakier. And it pulls in the upper rpm where the LT1 falls off.

[Injuneer]

The limited data quoted in the original post simply tells you the LS1 makes more torque at peak.... it doesn't tell you anything about low end torque. The Torque vs. RPM lines are not "straight".

I have a Corvette fuel injection manual covering the 91 L98, 92 LT1, and 97 LS1. It includes a small graph showing the torque curve for each engine. If you think about it, the Corvette factory numbers are probably more accurate indicators of each engine's actual performance, since the F-Body numbers were probably artificially reduced to keep it from looking like a better bargain than the Corvette:

L98: 340 lb-ft @ 3,200rpm
LT1: 330 lb-ft @ 4,000rpm
LS1: 350 lb-ft @ 4,400rpm

Looking at the torque curves, up to 2,000rpm the LS1 and LT1 are virtually identical. The L98 is only the width of the printed line lower than the other two engines.

At 2,000rpm the LT1 and L98 cross, and the L98 continues to climb while the LT1 torque curve actually lays over and starts to decrease slightly, until it levels out at 2,800rpm. At the same time, the LS1 curve is continuing to climb, and showing a greater torque than either the L98 or LT1. I would estimate the curve shows the LS1 is making about 25-30lb-ft more than the LT1 from 2,500-3,000rpm.

At 3,200rpm, the L98 lays over and torque drops rapidly. By 4,000rpm is is back down to maybe 220 lb-ft. The LS1 continues to maintain its significant torque edge over the LT1 all the way to redline. I'd say from 4,500 to 5,000rpm the LS1 is up by about 40 lb-ft.

Point is, the LS1 - at least the C5 version compared to the C4 LT1 - DOES NOT AT ANY POINT PRODUCE ANY LESS TORQUE THAN THE LT1. The idea that the LS1 has a "weak bottom end" would appear to be pure urban legend.... perhaps fueled by the feeling that the LS1 torque continues to build while the LT1 sort of peters out. The LS1's extremely strong top end makes it feel weaker on the bottom end, but the published data would appear to show that it isn't.

[raroZ28]

The idea that the LS1 has a "weak bottom end" would appear to be pure urban legend....

My thoughts exactly.

[Jay 02 TA ws6]

Fred, do you think it might have something to do with the smoothness of power delivery?

I'm not surehow you could mechanically quanitfy it... but you know the sensation I am talking about?

DOHC cars tend to "feel" slower than pushrod cars because they deliver the power more smoothly... All you have to do is drive an 03 Cobra to experience that first hand... it feels slower than my WS6 does, but in reality it isn't.

Although LT1 to LS1 is pushrod to pushrod, maybe something having to do with the LS1's firing order gives that sensation? I don't know, just kind of taking stabs in the dark here...

[Joe 1320]

At 2,000rpm the LT1 and L98 cross, and the L98 continues to climb while the LT1 torque curve actually lays over and starts to decrease slightly, until it levels out at 2,800rpm. At the same time, the LS1 curve is continuing to climb, and showing a greater torque than either the L98 or LT1. I would estimate the curve shows the LS1 is making about 25-30lb-ft more than the LT1 from 2,500-3,000rpm.

.

One thing that may add to the sensation is that supposedly, there is a torque management sub-routine built into the factory programming that momentarily reduces torque in automatics at the shift points to help make the transmission live. I remember reading about that when the LS1 first came out, but haven't heard about it since. Is this fact or urban legend as well?

The torque curve on the L98 sort of confirms the feeling I have when I drive mine. The low end punch of my L98 feels better than my LT-1.

All this tends to make sense. The mods I've done to my LT-1 either reduced parasitic loss in the driveline or added a little torque an HP. When I've gone up against basically stock LS1s, I take them out of the hole but I don't stretch the lead. They keep pace a length or two back until the 1/8th mile and then they slowly gain.If stock, they don't quite make up the differance. If they are mildly modded, they pull even in the traps. Well modded, they drive past me (for now) .

[fastTa]

Fred, do you think it might have something to do with the smoothness of power delivery?

I'm not surehow you could mechanically quanitfy it... but you know the sensation I am talking about?

DOHC cars tend to "feel" slower than pushrod cars because they deliver the power more smoothly... All you have to do is drive an 03 Cobra to experience that first hand... it feels slower than my WS6 does, but in reality it isn't.

Although LT1 to LS1 is pushrod to pushrod, maybe something having to do with the LS1's firing order gives that sensation? I don't know, just kind of taking stabs in the dark here...

The change in firing order was made to take advantage of the tuned length intake manifold runners, and the cylinder head design.

The idea that an LS1 has less overall torque delivery down low is pure urban legend. The reason some people comn to this conclusion based on their SOTP dyno is not because of the smooth delivery but just the opposite...the LS1 comes alive in the midrange to upper rpm's and does so very quickly. Put a significant cam in an LS1 and the midrange to upper rpm pull becomes violent. So people might make the mistake of thinking that the LS1 motor doesn't make good overall torque delivery down low.

LS1's make more better power under the curve period. I never really understood why people cared so much about having all of their available torque in the lower RPM's. Granted you need some torque to get your car going, but really....who cares about having a torquey motor down low? If that is all you care about then swap your motor for a dump truck motor. A torque curve in favor of higher RPM's is a good thing.