I will be replacing my L99 with an LS7 engine. It is saying I need part number
19243066 "ECU" I am wondering if that ECU works with an automatic or should I have my ECU programed to run the LS7???

 

Which ECM is that? The E38 or the E67? Both of those use modeled VE and the 6L tran uses modeled torque. LOTS of tuning required, definitely not a stab and go unless you're not picky on driveability.

Are you converting the motor to a wet sump?

 

Sweet. Curious, what is saying you need that part number?

 

Sorry I dont know what a wet sump is. I know it requires an exteral oil tank.
A new LS7 Crate motor says it requires an ECU, the 2008 model is different then the 2009.

 

I see that they did the conversion on the LS7 Camaro to the Wet Sump, do you know how that is done?

 

Quite possibly a dumb question, but why not just build the L99? If this motor follows the pattern of all the other LSx motors, it wouldn't take much more than bolt ons and the right cam to be making LS7 power.

 

+1.

You can get an L99 to LS7 levels and beyond, easily. Longtube headers and the right cam (plus a tune) is really all it would take, and even if you have those professionally installed by a race shop, you're talking no more than a few grand.

Or you can spend $15,000 on an LS7 and have to go to all of the trouble of pulling the engine.

 

Well, here is what I was thinking, start with the LS7 and later on throw a supercharger on that engine. I can peak out my L99 at 550 hp with a lumpy cam and a noisey exaust or have a smooth running LS7 and have much more potential down the road.

What do you think?

 

It seemed to me that Hennesse had his hands full getting the LS3 up over 550hp with a super charger?

 

I do like the idea of saving money for sure, but i love the cubic inches!

 

When GM decided to put a supercharger on an LS engine, they considered using both the LS3 and LS7 as a starting point. They ended up going with the LS3 because its thicker cylinder walls are better suited to the increased cylinder pressure. As a result, both the LSA (CTS-V) and LS9 (Corvette ZR1) are based on the LS3 (they use the exact same block!).

The L99 is just an LS3 with VVT, DOD, and a different cam profile -- the block and heads are identical. I've seen 505 hp at the rear wheels from an LS3 with a big cam and longtube headers. That translates to roughly 575hp at the flywheel.

With a VVT-enabled L99, you should be able to achieve similar peak horsepower while also maintaining a broader torque curve than any non-VVT engine.

Personally, I think the L99 is the most interesting engine GM has ever made from a modification and power potential standpoint.

If it were me, I'd stick with your L99 and see how far you can get with it. If you still want the big cubes, get it bored and stroked to 418ci (that's 97.9% the displacement of the LS7). You'll still have thicker cylinder walls than an LS7, making it still the better platform for forced induction.

You can do all of that, including the supercharger, and you'll still probably have spent less than you would on a bone-stock crate LS7.

Then you can use that money to beef up the rest of the drivetrain. You're going to need it!

 

my 415ci LS3 (auto trans) is a standard bore, just add crank,rods,pistons, heads

really quite a simple build to gain c.i. and hp

 

Is this in a Corvette or a Camaro (or, I suppose, a G8 GXP)?

 

2010 camaro

 

Cool. So you pulled out the L99 and swapped in a 415ci LS3? Or did you have the L99 converted and modified?