# ls2 upgrades



## AaronGough (Nov 20, 2008)

Ok guys, I recently talked to one of my friends who has an '05 corvette with the ls2 and 6 speed, just like my 05 GTO. He told me that a friend of his said that you can take the heads and intake off of a ls3 and make the motor put out right at 500 horses. Now personally that sounds like an idiots dilusions of grandeur, but I still won't close my mind to the awesomeness of the ls2. Any insight on this would help.


----------



## B-ville Goat (Oct 5, 2008)

Not so. I do agree the LS3 stuff is good, but not worth 100 on it's own. To take full advantage of those heads and intake, you would need a cam and probably long tube headers to see that number.


----------



## GM4life (Mar 18, 2007)

AaronGough said:


> Ok guys, I recently talked to one of my friends who has an '05 corvette with the ls2 and 6 speed, just like my 05 GTO. He told me that a friend of his said that you can take the heads and intake off of a ls3 and make the motor put out right at 500 horses. Now personally that sounds like an idiots dilusions of grandeur, but I still won't close my mind to the awesomeness of the ls2. Any insight on this would help.


Yes you can use LS3 heads and intake, but you wont see 500 horse. The LS3 in stock form only makes 436 horse. The LS3 heads are better than the LS2's but to get that number you need a cam, tune and exhaust.


----------



## AaronGough (Nov 20, 2008)

Alright, thats what I was thinking but I just wanted to ask around and see cause it sounded a little far fetched to me.


----------



## Aramz06 (Mar 2, 2008)

AaronGough said:


> Ok guys, I recently talked to one of my friends who has an '05 corvette with the ls2 and 6 speed, just like my 05 GTO. He told me that a friend of his said that you can take the heads and intake off of a ls3 and make the motor put out right at 500 horses. Now personally that sounds like an idiots dilusions of grandeur, but I still won't close my mind to the awesomeness of the ls2. Any insight on this would help.


 LS3 heads are obviously better, but 500 is definitely out of the question.


----------



## fergyflyer (Apr 18, 2005)

The LS3 has more than just the heads. They are .2 liters larger than the LS2. I think they also have a different size throttle body. They are underated at 430 or 436 hp and are closer to 450 hp. 

I've got a friend with an 07 C6 Vette 6M LT's and Borla stingers. He's done a Vararam intake and had a dyno tune. He made 389 at the wheels. Stock he was in the high 330's. 

Another friend with an LS3 put his car on the dyno stock and put down high 380's. He did LT's, a Haltech intake and the stock performance exhaust and a dyno tune and he got 431 at the wheels. I guess you could say that was 500 flywheel hp but I think the LS2 would be hard pressed to match those numbers without a cam.


----------



## fattirewilly (May 26, 2006)

AaronGough said:


> Ok guys, I recently talked to one of my friends who has an '05 corvette with the ls2 and 6 speed, just like my 05 GTO. He told me that a friend of his said that you can take the heads and intake off of a ls3 and make the motor put out right at 500 horses. Now personally that sounds like an idiots dilusions of grandeur, but I still won't close my mind to the awesomeness of the ls2. Any insight on this would help.


I'm sorta diggin this article from Pontiac Enthusiast cause you can pop the hood and everything looks normal. Result is +86HP over a car with CAI & SLP exhaust bolt ons.

Below is a parts list from the article. Please let me know what's left out or what you'd change. I like the end result with 25 mpg. However they make no mention of how it drives in traffic or what the power band is like.

L92 heads, assembled, $400 each

L76 intake (no rails, or TB) $250

Comp Cams XER273HR .581/.592 224/230 and 114 lobe separation (these numbers mean little to me......is this a mild cam?)

Comp Cams pushrods

Offset Rocker Arms (no description given)

1/2 inch spacers to mount under fuel rails

Pacesetter Headers (I'd go Kooks w/high flow cats)

They say they got $2,000 in it for the 86 horse increase. The test car already had a CAI and SLP exhaust, making baseline 346 HP. 430 HP after, no mention of torque or if the tune was touched. Still returned 25 mpg highway.

The L92 combustion chambers are 70cc, a touch smaller than stock, thus raising the compression ratio (so they say). Would a setup like this be okay to throw a maggie on top of?


----------



## AlaGreyGoat (Jul 6, 2006)

You really need a lower comp ratio for forced induction. Then you can
pack in more air/fuel to raise it back up again. If you have a high
static compression ratio, then you can't pack in very much, the comp ratio will go way too high.

Larry


----------



## Sticks_n_Stones (Mar 10, 2009)

bump for a usefull thread. Question though: if the commonly held truths are correct then: Pace Setters catless headers give you 30hp, the cam is another 35hp. Sooo, the heads give you? 22hp? The real question buggin me RIGHT NOW, is: how do the aftermarket heads such as AFR and Patriot fare against the LS3's 330cfm flow rate? Would the extra 20hp that those heads supposedly could give you be worth an additional $1400+ over the LS3's?


----------



## alienforce1 (May 24, 2012)

Been surfing this forum for the past 5 months since i bought my 06gto. Been trying to find good info on swaping to the ls3 heads and intake. This thread should be a sticky. I wonder if there are any updates for this combo like with the porting and polishing. Also how much hp and tq gain u would get with just port and polished ls3 heads and intake.

This is my first post. I always try to find the question and answer for a long time before i post. This thread hit questions and answers on the nail.


----------



## ZEIKE524 (Dec 28, 2010)

Sticks_n_Stones said:


> The real question buggin me RIGHT NOW, is: how do the aftermarket heads such as AFR and Patriot fare against the LS3's 330cfm flow rate? Would the extra 20hp that those heads supposedly could give you be worth an additional $1400+ over the LS3's?


This would be an answer i want to know


----------



## svede1212 (Nov 1, 2005)

From what I understand there isn't much benefit on a normal cubed engine to P&P. Bumping compression with combustion chamber work or milling is effective tho.


----------



## pete180 (Dec 26, 2011)

Heads are useless without a large cam to take advantage of it. You can't really run a very large duration cam without slapping a valve on the piston. With associated mods(1 7/8 headers, exhaust, ported intake) 470rwhp is very doable. 

You can use your stock ls2 rails and injectors on the ls3 intake. Porting the intake runners of the L92's isn't needed(polish only, they already flow over 300cfm and would only slow the velocity of the port), I would port the exhaust runner and do the bowls. Throw in a 222/230 cam and it will be a nice setup.

I'm in the process of collecting parts to do my swap. Have an LS3 intake already, will be using my stock rails and injectors. Not going to cut the heads just use a .028 gasket instead of a .051. Compression should be around 10.8. IMHO an LS3 top end is great for FI(although the decks are thinner, it shouldn't be a worry under moderate boost levels), by cramming the engine full of air you'll be able to take advantage of the heads that a NA build isn't able to.


----------

