Difference between LS3 and LT1
 

Not being the engine guru some of you are, I was wondering if someone could explain just some of the major differences?

Thanks
Dave

LS3 is 6.2 liter pushrod with aluminum block and heads. The LT1 is the same pushrod aluminum case/heads but adds direct injection, VVT (variable valve timing) and AFM (active fuel management).

Edit: Forgot to mention LS3 is 426 HP and the LT1 is 455 HP

By the same I mean it's aluminum but it is a completely new engine not an upgraded LS3. I hope that clarifies and makes sense.

It is important to note that only the A8 is listed as having AFM. The M6 is not.

New LT1 owners may want to add a catch can as the direct injection has caused Vett owners issues with valves getting real dirty real quick. No more gas washing the back of the valves with direct injection.

Catch can may help keep the PVC oil vapors off the valves.

The LT1 has an elaborate oil separation system built into both valve covers, but that's interesting to hear the C7 owners experiences.

BMW (and basically everyone else with DI) has had similar issues. Road and Track said that BMW blamed it on US drivers taking it too easy on the engines, so the rings never broke in and sealed. This may make for a case to do a "hard" break in for the LT1, such as full throttle runs in 4th from 35mph up to put loading on the pistons.

I read that the Camaro's LT1 has an oil sparator, but I didn't know if the C7 has it or not. The way it was phrased in the article I read, it sounded like it was unique to Camaro, but since it was never stated as such, I guess I shouldn't assume.

It sounded to me like GM added the oil separator to the Camaro LT1.

Yes, and I am sure that turbo boosting a 4.4L engine up to 402HP has nothing do do with the major oil loss these engines are suffering (that is sarcasm just so you know), and hence the fouling of the intake. They had to change the recommended oil life from 15k miles to 10k miles. In this case, it's not just the DI that is causing issues. That engine has MAJOR issues. Here are some of the issues quoted from an article that explains why BMW now requires a new battery install EVERY OIL CHANGE:

"BMW of North America has recognized a number of N63 components with high failure rates, including timing chains that stretch and snap, leaking crankcase ventilation and fuel lines, and malfunctioning fuel injectors, mass airflow sensors, and vacuum pumps."

Some of these issues are related to too much of the combustion blowing past the rings (lots of boost), but there are also major heat issues since they have reverse flow heads and the turbos sitting the V of the engine.

Here is a link to the article:

http://www.roadandtrack.com/car-cult...ick=welcome-ad

The reverse flow heads were an effort to shorten the intake path, but it is a very clumsy (and not short by the way) solution. I much prefer the way GM uses a liquid secondary on their intercoolers. Super short intake path, and no heat issues. Plus, it's more efficient at cooling the intake anyway.

I wonder what the batter issue will do to depreciation in these cars. For now, the new batter every oil change is covered by the warrenty (or CCP), but what happens after that? That's got to be one hell of an expensive oil change.

I can't imagine paying to replace an AGM every 10k miles on top of the astronomical German oil change costs.

I havn't looked it up, but I am guessing that ain't a cheap battery. Plus, the oil used ain't cheap either. I think it's made from unicorn blood by the the way it's priced.

Forget the oil, why not just change the engine every 10k mi. That should fix it, and it would be cheaper too. (sorry, my sarcasm it out of control today!)

I owned a '10 Corvette GS with LS3 and now own a '14 C7 with LT1 and you cannot believe the seat of the pants difference between the two engines. The power comes on at a much lower RPM with the LT1.

Just noticed I better change my avatar to one with my Camaro and C7. Picture time the next sunny day.

yes this was mentioned that the 16 Camaro's (not sure about current Vette's) LT1 will have an oil-separation measure. So it sounds like a catch can will not be necessary.

As stated above, LT1 makes much more low and midrange torque than the LS3. Just check out the GM engine dynos on the two.

Great to hear. I always felt my LS engines were a little soft down low, but I had never driven one in a Corvette.