nelson71

Road and Track has pics of the new Pontiac G8 which is basically an Australian Holden. The article says the available V8 will have 362hp. Does anyone know any specs on this motor? I assume it has L92 heads and the l76 car intake? If so shouldn't the output be over 400?

http://www.roadandtrack.com/article....rticle_id=4734

Katech_Jason

iTrader: (19)

Probably a different cam.

nelson71

After doing some digging online I see that the 362 hp Holden engine is called L98 and that it has 10.4:1 CR to the LS2's 10.9:1.

Aren't these new Aussie engines supposed to be using the L92 style heads?

If they do have L92 heads and only produce 362hp that should leave the tuners ALOT of room for improvements!

GR33N GoblinM6

iTrader: (14)

what does the L76 engine come in, here in the US?

Scoggin Dickey

iTrader: (34)

It comes in some of the 2007 trucks.

nelson71

Is L76 the code for the 367hp vortecmax engine?

Apparently L76 is the code for the standard Commodore engine that they rate at 260kw

The upgraded 6.0 is called a L98 rated at 270kw which converts to 362hp.

I wonder if the Vortecmax engie is the same one used in some of the Aussie cars? The point is what engine we are going to see in the G8 and what components its made up of. I know it will be officially released within the week, but what fun is waiting?

nelson71

Bump

I did a little research and found that L76 is the code for the 6.0L suburban/YukonXL engine. Now that the G8 info is out I see that it is going to have the Aussie L76.

I am assuming that the Aussie L76 has what we are referring to as L92 heads. Is that correct?

The official info says that it has active fuel management and 10.4:1 CR.

This looks to be the first performance application of DOD. Does that limit or affect the cam profile or valvetrain? Does it limit RPM?

NO-OPTION-2002

iTrader: (2)

http://media.gm.com/us/powertrain/en...2007/07car.htm = 2007 Car engine specs.

http://media.gm.com/us/powertrain/en...07/07truck.htm = 2007 Truck engine specs.

More info can be found here! https://ls1tech.com/forums/generation-iv-internal-engine/431724-2007-new-engine-info.html

Bo185

Then whats the LY6 6.0L in the new HD's? Its rated t 353HP 373 torque. Whats it have in it, different cam, less compression?

It's a Gen IV and has VVT, Active Fuel Management, and L92 heads.

NO-OPTION-2002

iTrader: (2)

Same pistons and heads (L92). Different cam.

LY6 = 353hp/373tq.
L76 = 367hp/375tq.

Sharpe

iTrader: (7)

Oh, great. Now there is both a Gen IV engine and an intake called L76? Is that right?

That's about as fool as giving a block the propper name LSX when everyone uses LSx to refer to a series of engines. Oh wait, they did that.

Also, just throwing this out there, these horse power numbers are all marketing, as we F-Body owners are all to aware. Not saying that's the only difference or anything, as people have pointed out other differences, just saying keep it in mind.

nelson71

It looks like the Aussie L76 tht we'll see in the G8 and the truck L76 are at least very similar if not the same engine. One thing I noticed in the media links is that the truck engine has variable cam phasing and that is not mentioned in Pontiac or Holden promo matrial.

Bo185

Then the derated L92 in the GMC's is a detuned L92 with the same cam as the caddy.

Oh do you know were to find the Factory cam specs for each engine?

Bo185

The L76 VortecMax engine should have the truck style L92 intake. I bet they are the same.

nelson71

I think the intake is referred to as L76 because it came off of this L76 Australian car Engine. That same engine is the same one that is going to be standard in the G8 Pontiac which like the GTO is a rebadged Holden.

I am fairly certain that the hp figures are not SAE certified yet. They just took the 270kw rating the Aussies use and converted it to hp. It may end up with a completely different rating by the SAE.

I've been reading for months about the potential of the L92 heads and the L76 intake. Unless I am mistaken it appears that this car will come with that combe form the factory. That's why I was surprised by the low hp rating. If this thing is completely detuned for economy and emissions, I can't wait to see what it will do with a cam and a few bolt-ons.

Scoggin Dickey

iTrader: (34)

Yea, the L76 intake is not just "called" that for fun...it's off the L76 Holden cars.

Sharpe

iTrader: (7)

Ohhh. Okay. I see now. That's why I asked if I was right, 'cause i wasn't sure. Still, wouldn't have surprised me. I didn't even know that there was such thing as an L76 engine.

pkincy

iTrader: (1)

I suppose the real question is what it will take to remove DOD and put in a stroker crank. I think the L92 guys will have that well figured out by next year.

The other important factor is what computer.....I presume the E67, and we gotta hope the tuner guys crack that by early 08.

With those 2 things going on the G8 will be the real deal. I stayed away from the GTO since it was 300 lbs heavier than my Camaros, but for a 4 door I can do 4000 lbs.

Perry

Bring the Noise

first question: How to remove DOD/AFM?
Replace the DOD/AFM cam and lifters with a LS1/LS2/LS7 style cam and lifters.
The cam will be specific for the head type (ie ls4 uses ls6 style heads and L76 and L92 use heads based off of the ls7 design).

Second Question: Stroker Crank?
Any Aftermarket crank that is designed for a wet sump LS based motor will drop into a LS style block (be it a LS4 5.3L, a L92 6.2L, or a custom built LSX 441).
The bottom of the block may need to be clearanced for the cranks larger stroke.
Typically you don't want to go beyond a 4" stroke due to cylinder sleave length (in the block). Tall Deck LSX will take longer cranks though...

Note: You can actually drop a LS7 Dry Sump crank into any other LS block but you will need the dry sump oiling system and front drive accessories to work with the LS7 crank (ie pulley, water pump, etc).

Third Question: Which ECM to use?
The computer to use will be dependent on what you are doing (sounds confusing but its actually very simple).

If you want to keep DOD/AFM while retrofiting a LS4, L76, or L92 into an older vehicle then you will need one of the newer ECM's along with a wiring harness (you'll also need a 58x timing gear on the crank, that is if you go stroker crank).

If you want to retro a L92 longblock into a 99 Silverado then you need to do something along the following.
1. Swap out the crank timing gear for the 24x timing gear (used in the 99 pickup).
2. Remove the DOD/AFM cam and lifters and put in cam spec'd for the heads and your requirements along with a set of ls1/ls2/ls7 style lifters (GM or aftermarket).
3. Cam timing sensor cable extension (look up ls1 to ls2 conversion stuff... its been around for a while now).
4. You would also need to change out the fuel rail system as the 99 trucks probably had a return line on the fuel rails where the L92 fuel rails do not.
5. Retune the trucks stock ecm for the new motor.
Note: 99 to 05 trucks/SUV's, C5's, and 4th gen Fbodies would go through a similar process.

Essentially the ECM, Wiring harness, and crank trigger need to be matched up (see it is simple).

jtl12419

iTrader: (13)

Another challenge when retrofitting LS2/L92/L76 into an LS1 position is physically cabling the the throttle.

I did not think of this when buying my FAST90mm TB, but there are no provisions for throttle linkage on the stock L76 IM. There is one lister who is selling a bracket, anyone else out there figured it out?

My build is about 75% done, I have the shortblock assembled, and am waiting for rockers/valves/springs/pushrods to finish the heads. It will be interesting to tie in the Fuel/electronics when this is all done.

Any issues on the knock sensors? I am assuming that the LS1 and LS2 knock sensors are the same?

Jolly