1gary

Almost everything I have looked at for the LSx engines.People are raving about hp ratings.Bigger aftermarket heads and bigger cams.That's fine,but are these engines all torque later in the rpm range??.

So here is the question:

Can anyone show the torque ratings at what rpm??.

Post the mods done

Any right off idle and big torque numbers??.

More interested in N/A engines,but not excluding turbos

All OEM blocks please.No aftermarket blocks.

Any one LSx known for torque over the others.I would guess the 6.0


Thanks.I am really interest in see what you guys say.And I posted here by

no mistake.I respect all you guys knowledge on LSx engines.

Lonnie P

Typically you would look at the truck engines.

A smaller cam, with the long runner truck intake will be where the torque is at.
Large engines or those with the longest stroke is what makes the most torque.

The small port of the LS2 should edge out the LS3 style head for this reason also.

Usually those building a stroker LS1/2 are not trying to build torque engines, but something that puts down power at 6000+ rpm.

Obviously forced induction is where you find the biggest torque numbers.

What you need to focus on is the intended usage of the vehicle & go from there.
Numbers are just that... numbers. Overall performance is achieved by maintaining the broadest torque over the operating range of the engine... as installed in the vehicle. Torque below the launch rpm is not useful.

five7kid

iTrader: (14)

I'm going to have to get my stroked 6 liter dyno tuned. It will be a chassis dyno, so you'll have to take that into account with the results. Hope to have it done in late March or early April.

UnstableAviator

A typical head/cam LS1 (346ci) build seems to put anywhere from 320 to 350 rwtq at the start of the dyno pull at 2500 rpm. Build from there and peaking around 5000 and near 390-400rwtq. Dig around on 'tech, look at a few dyno graphs, you'll start to see a typical dyno sheet pattern for a given cubic inch build.

1Gary, have you driven a modded (even bolt on) LSX? They are extremely responsive to throttle inputs and have a very broad power curve. Fun to drive at 2000 and even more fun in the 5000+ range.

Lonnie P

Just keep in mind that any chassis dyno results through an automatic trans will be misleading below the stall speed of the torque converter, giving a false high reading, unless done with a lockup style converter.

five7kid

iTrader: (14)

Exactly, that is part of what needs to be taken into account with chassis dyno numbers.

Z28FAST1

^^^Agreed. The most impressive aspect of the LSx is not peak TQ numbers rather the broad power band.

Orr89RocZ

iTrader: (20)

I will disagree here. My auto 99 ls1 bolt on car doesnt have much til about 3000 rpm. In fact you could mash the throttle from dead stop on street tires and it would hook and slowly roll out til near 3000 and it would then break tires loose. Just not alot of torque down there. With 3200 stall they work. Stock cars run best with 3800-4000 stall and cammed cars could see 4000-5000 rpm converters to run best track times. Torque curve is flat but off idle its no big block or tpi L98 even.
My bolt on car didnt dyno as high as most, only making 320/318 i believe but it ran 12.2's at 111-112. 318 peak torque while my L98 with stealth ram made 315wtrq. So pretty close on torque numbers


My 6.2 truck feels fine off idle, feels torquey. Dyno'd 330whp after tune with a peak torque around 370 but couldnt keep trans from downshifting so that was at 4000 rpm. I expect 10-15 lbft more at 3500-3800 rpm. But even with that motor, from a dig it really doesnt feel like its hauling until 3000 rpm. Maybe thats the vvt kicking in but definately a difference at that rpm on up to redline

Another 6.0 truck with few bolt ons. Air intake/ muffler. Stock manifolds. After tune it made 300 whp and 370's trq. Pretty healthy. Truck intakes do help make more torque

Making 400 wtq with heads cam ls1 is doing very well imo.

UnstableAviator

I guess my T56 and 430's are making up the difference then. I have zero traction in 1st and can in fact spin the new KDW2's at even part throttle. I would imagine an auto with 3.23's would feel markedly different.

Orr89RocZ

iTrader: (20)

Auto stock stall would be different no doubt. Maybe it was gearing but i had 2.73 and couldnt light them up from a dead stop dig run even in the rain lol. Once over 3000 it blow the tires off. The L98 stock with 2.77's had no problem roasting tires from dead stop but a slow roll it would dead hook, unlike the higher hp ls1. Just different power band and curve shape. Same with my truck but it has 31" tire and 3.73's and a steep first gear trans ratio. 99 ls1 with stall was very fun even with 2.73 gears. Goin to 3.73 was a waste of money. Only a tenth gained in 1/4 mile and lost 5 mpg mileage