Figured I'd participate rather than just lurk for once.

 

That Corvette graph seems weird, because it shows the LS6 only reaching a torque peak of 390 lb-ft, but it was rated at 400 lb-ft @ 4,800 rpm in the '02-04 Z06.

Here's the CTS-V graphs overlaid:

 

put an 05V an 06V heads up bone stock and youd never be able to tell which car had which motor. bottom line

 

A good friend of mine has an '05V and he comments every time he drives mine about the low-end difference.

We've yet to race them though. Partly because we were both tire limited, he has General UHP's and I had RS-A's (now Wintersport M3's). So it seemed like more of an exercise in traction management than any kind of performance comparo.

But I'd like to run them some day just to see.

Edit: Just to be clear, I'm not trying to fuel any kind of angst or hate or whatever seems to go on about the motors. But the LS2 clearly has more average horsepower and torque. Therefore, all else equal, it will be faster. A lot faster? No. Noticeably faster? I dunno, probably not easily, but there is about a 20 lb-ft difference for about a 2,000 RPM window. Not huge, but not trivial either.

I bought an LS2 car because it was still under the original warranty, and I could find one in the colors and miles I was looking for. I'd happily own an LS6 car if it had met those criteria too. But they were all too old to still be under the original 4/48 warranty.

 

Both engines are Great but if you use a Supercharger the edge goes to the LS-6 due to its valves (run cooler) and the almost .5 in compression. On a Supercharger that makes a Big difference.

 

The 4" bore of the LS2 opens up the opportunity for LS3 head/intake setups...but the 04-05's are so much cheaper! Both are great engines.

 

***EDIT*** Nevermind. Didn't realize this thread was over 5 years old...


I own an '08 Viper. I wasn't aware the C6ZO6 performed better than the Gen4 Viper? How?

The Viper is definitely more rare. Looks are subjective, but you have to admit the Viper is waaay more aggressive/tougher looking.


You said it - not me. 510 cubic inch Veee-Ten.







With that said, I honestly have no idea if the LS6 or LS2 is better, but I'd love to own a ZO6 as well. I need a 3rd job...

 

you wont have your V in three years...haha. i hope i have a V2 in about 2 years.

 

I am not sure that it is worth upgrading to LS 3 Heads, Hot Rod just compared all Factory and Aftermarket Heads and Ported LS 6 Heads beat them all. Not by much but thru the Bandwith they were better. Dollar for Dollar Supercharging is the way to add another 130 HP and not loose any driveablity. We sell Magnachargers, call us, our installs look better then factory. As far as Viper - Vette every year in the last 10 the Vette beat the Viper over all and for alot less money. Vipers are a nice car but I also have a Vette and will always go that way 1st. Topline Viper from factory against ZL-1 Vette, Vette won. Althou if I was to go new it would be the Z06 and add a Magnacharger, same or better performance and a lot more money in the pocket. As far as the 2004-05 V's being a lot cheaper then the 2006-2007 V's, sorry I don't see that either as matter of fact since the New V's the prices have held or even gone up a little in the Chicago Market for a low to moderate mileage car.

 

Thank you for noticing this as well. I thought I was going crazy as I've noticed this as too. A few years ago, before I bought my Saab they were more readily available, and more reasonably priced. The V2s have definitely increased the resale prices of used V1s. I remember seeing them a few years ago listed in the mid teens with 20,000 miles on them. Now you are looking at mid 20's for something even close. There is one listed at a dealer down the street from me for $18,000 (recently reduced) with 80,000 miles on it!

I'm currently in the market for one and I am having a hard time justifying it with the prices the way they are. I'm still looking and will pull the trigger when I find the right deal on an 06 or 07.

From the research, and this is only research, it seems like the LS2 has a little more potential. Smoother torque curve and more cubes is always a good thing. The only draw back to all that torque is the weak rear-end.

 

I would agree that the V2's have increased or halted the decline of prices on the V1. But coming from someone who has searched for a V1 for two years, the 04's and 05's tend to be a bit cheaper. I mean, it makes sense. We can assume that most cars depreciate at a certain rate per year. More years of depreciation = lower cost. Would you disagree? There are a lot more factors that come into play here. But for two identical cars of different years, the older car is usually less expensive.

As for the LS3 vs LS6 comparison, I'm not exactly sure how you came to the conclusion that the LS6 heads outperformed the LS3 heads....here's the actual data from hotrod magazine:

Test 7
TEA LS6

Retail price: $1,320 (porting on customer-supplied head castings)
Intake valve size: 2.055
Exhaust valve size: 1.575
Intake port volume: 226 cc
Exhaust port volume: 78 cc
Chamber volume: 63 cc
Peak power: 618.1 hp at 6,300 rpm
Peak torque: 555.3 lb-ft at 5,400 rpm
Average horsepower (3,000-6,500): 476.1 hp
Average torque (3,000-6,500): 521.8 lb-ft
Torque at 4,000 rpm: 515.1 lb-ft

FLOW DATA: CFM (AT 28 INCHES)
LIFT
INTAKE
EXHAUST

0.050
33
26

0.100
66
60

0.200
144
118

0.300
214
163

0.400
269
199

0.500
310
223

0.600
329
235

0.650
330
230

0.700
310
231

It seems like just about everyone with a grinder offers ported stock LS1/2/6 heads, so naturally we had to choose at least one set for our test. It didn't make much sense to have 20 to 30 sets of ported LS1/2/6 heads, so we decided to pick one set to represent what was possible with the factory castings. Naturally, we selected the cream of the crop in terms of factory castings-the LS6 head. Our ported LS6 heads came from the flow wizards at Total Engine Airflow. The TEA Stage 2 heads featured the requisite CNC porting, a 2.055/1.575 valve package, and 63cc combustion chambers. As delivered from TEA, the LS6 heads offer 330 cfm combined with impressive midlift flow numbers. It bears mentioning that the ported LS6 head was the lightest of the bunch, which as you know is the same as offering more power. Down just a few horsepower compared with the best of the bunch, porting a set of stock heads is obviously a very cost-effective alternative to purchasing new castings-especially if you already own a set of LS6 heads.


Test 5
Mast Black Label LS3 (Small Bore)

Retail price: $2,998
Intake valve size: 2.165
Exhaust valve size: 1.60
Intake port volume: 257 cc
Exhaust port volume: 86 cc
Chamber volume: 64 cc
Peak power: 620.1 hp at 6,600 rpm
Peak torque: 563.3 lb-ft at 5,300 rpm
Average horsepower (3,000-6,500): 477.4 hp
Average torque (3,000-6,500): 523.4 lb-ft
Torque at 4,000 rpm: 514.3 lb-ft

FLOW DATA: CFM (AT 28 INCHES)
LIFT
INTAKE
EXHAUST

0.050
34
24

0.100
70
52

0.200
142
110

0.300
215
143

0.400
274
205

0.500
313
225

0.600
342
239

0.650
352
247

0.700
335
250

We know this rectangular-port head really doesn't belong in this cathedral-port head test, but we included it for a number of reasons. One was the fact that (just like the cathedral-port heads) this small-bore rectangular-port LS3 head was designed specifically for a 4.030-bore application. As such, the Mast head is a market competitor for the cathedral-port heads, despite the LS3 intake and offset rocker arms required. The second reason is that we wanted to see just how the considerable change in port volume (compared with most of the cathedral-port heads) might affect the low-speed power production. The general consensus is that larger port volumes decrease cylinder filling at lower engine speeds. Were that the case, we'd expect the big ports on the Mast LS3 heads to lose power down low, but that was not the case, as despite intake port volumes of 257 cc and the largest 2.165-inch intake valves, the Mast heads offered the highest peak torque output of 563 lb-ft at 5,300 rpm. The oversized port volumes didn't hinder the average power numbers, either. As we went to press, Mast announced it is introducing a far bigger line of 14 different LS heads, including cathedral ports.


....So I guess GM made a mistake in creating the LS3. They should have just stuck with the LS6 right? Everyone on LS1tech is going to be really disappointed when they find out that the $ they just spent on their LS3/L92 - 370/4XX setups was a complete waste! I'm not saying the 243 heads are bad...far from that. But changes (improvements) are made for a reason, and the reason usually is not to decrease performance. But, for everyone's sake, I'm not going to get into a pissing match with you. Its obvious that you own a "Viper" and have it all figured out.

 

Ls6 = gen iii
ls2 = gen iv = stronger block

 

they are both aluminum blocks and i doubt youd see much if any difference in how much power they can hold. An iron block 6.0 yea, but not an aluminum.

as for the 243 heads vs ls3 heads on an ls2..........ls3 heads/cam will blow a 243/cam car away power wise.

 

i would go with the motor which offers more displacement. both are very similar, but once you start modding the gap grows.

 

Okay I admit I screwed up on the LS6 - LS3 head must have skipped over the part about the LS3. However they did state that all around you could not beat the Ported LS6 head. But as far as the comment on the Viper goes, it funny On a different forum I stated that for the last 10 years the Vette has the Viper every year including this year with the ZL-1. However I would rather buy the Z06, put a Magna supercharger on it and have over $20,000.00 in my pocket. Besides my V my other Toy is a 79 Twin Turbo Vette 1100 Hp, Pumped Gas with a Snow System on it and I Love to pick on Vipers. Who would think a 79 Vette could beat a lot of Vipers?

 

^^^^ yes

 

Ls6 ftw!!!

 

i think what all of us really thing is...

LSA FTW!

 

I'd probably take the LS2 with a little extra cubes.

 

Werd..