Gen V V8 Info

[Roadkillz]

Originally Posted by Enginerd

I'm not too sure about that. It says "independent intake & exhaust VVT," which the new LT1 does not have. Though the other info looks legit, but that is a big one to get wrong.

This sheet was very early on, and based on what I read in the LT-1 release they looked at such a system but decided against it on the LT-1.

Also, for the ATS V they are looking at both a TT V-6 and the 6.2L V-8 engine. I heard that the main guy calling the shots wants a TT V-6 in the ATS V (I think this is a HUGE mistake) however they were having issue with that engine in early development. So there is still hope that the right engine will find its way into the ATS V beast.

[spd98]

Originally Posted by Longtimer

The prelim numbers for the LT1 are also balanced - 450 / 450. That's showing 438 for the tq.

Rmember in this day that the engine ratings will not be the same in the ATs and in the C7. The certified numbers use production intake tracts and exhuast.

Also keep in mind that GM hinted at 550 for the LSA in the ZL1. It ended up quite a bit higher.

[Roadkillz]

Originally Posted by spd98

Rmember in this day that the engine ratings will not be the same in the ATs and in the C7. The certified numbers use production intake tracts and exhuast.

Also keep in mind that GM hinted at 550 for the LSA in the ZL1. It ended up quite a bit higher.

I am not holding my breathe for a huge difference in the 450BHP rating currently thrown around and the certified rating. Remember this engine has AFM and the AFM lifters really limit how aggressive the cam can be.

A better comparo would not be between the LS3 and the LT-1 but between the L99 and the LT-1 engine. Both engines have VVT and AFM, with the LT-1 engine adding direct injection.

People forget that while the manual transmission Camaro SS got the LS3 engine rated at 426BHP the automatic car got the L99 rated at 400BHP. The reason that the manual car did not get the L99 engine was an issue with AFM working properly and sounding right with manual transmission cars.

Obviously with the LT-1 they are talking a ton about its flat torque curve.

I expect it to be an amazing engine the Gen V engines, though the LT-1 version is obviously the most tamed variant in the Corvette.

[spd98]

Originally Posted by Roadkillz

I am not holding my breathe for a huge difference in the 450BHP rating currently thrown around and the certified rating. Remember this engine has AFM and the AFM lifters really limit how aggressive the cam can be.

A better comparo would not be between the LS3 and the LT-1 but between the L99 and the LT-1 engine. Both engines have VVT and AFM, with the LT-1 engine adding direct injection.

People forget that while the manual transmission Camaro SS got the LS3 engine rated at 426BHP the automatic car got the L99 rated at 400BHP. The reason that the manual car did not get the L99 engine was an issue with AFM working properly and sounding right with manual transmission cars.

Obviously with the LT-1 they are talking a ton about its flat torque curve.

I expect it to be an amazing engine the Gen V engines, though the LT-1 version is obviously the most tamed variant in the Corvette.

First off the 450 isn't a rating at all. Gm has say at least. The lifters on this engine are NOT the same as the LS ones they are MUCH smaller (lower mass means less force on the valetrain). Then you also have to remember that the cam size and duration have to be factored into how well everything else flows. If the ehads and the intake flow substantially better you don't need as big of a cam.

My point is that there are plenty of other factors to consider. This engine has higher compession and more eff on the combustions side. Then you also have adjustable valve timing as well as fuel timing (a huge amount of potential KR elimination).

GM will, like always, leave HP on the table, the question is how much?

[Roadkillz]

I wonder which tuner will be the first to make a 7.0L LT-1 V-8 engine, I know that LPE offers a 570BHP 427 LS3 engine for $20,000. Katech has a 427 LS3 with an est. 600BHP, so how much would a 427 LT-1 engine produce given that it uses VVT, direct injection, and already has a 11.5:1 compression ratio.

BTW, for the top of the line Corvette GM should benchmark Katechs ultra track attack.... 717BHP and 2,900 pounds...

[sixpeedreams]

WHAT IS WITH the plastic engine covers!?!? Let us see the engine for gods sake. If the intake manifold is rough looking then spice it up a little but come on. The SBC is the heart, soul, history, and half the draw of the Corvette. Don't hide it. How can they not get that???

[Roadkillz]

Originally Posted by sixpeedreams

WHAT IS WITH the plastic engine covers!?!? Let us see the engine for gods sake. If the intake manifold is rough looking then spice it up a little but come on. The SBC is the heart, soul, history, and half the draw of the Corvette. Don't hide it. How can they not get that???

I completely agree with you, GM doesn't make good looking chevy small block V-8 engines anymore.

IMHO the last good looking Chevy Small Block V-8 was the L98 engine. When the LT1 engine replaced the L98 engine it wasn't a bad looking engine however it started a trend where you had one design covering the top of the engine.

Ford makes good looking engines, granted their engines generally have not had the performance of the chevy small block engines. Really not until 2011 where the 5.0L V-8 returned could you compare the Ford V-8 to the Chevy V-8. Also the C5R and C6R race cars have really good looking engines as well as the Viper V-10.

I just can't believe that this is one area where GM continues to concede to everyone else in the market.

On the other hand, engine covers have become more common place now days because its an easy way to hide wires. Also the engines covers often work to reduce noise, its just for a performance car people want to see a work of art engine. This market segment also doesn't mind hearing extra noise as long as its good noise.

I will admit though, that I think this engine looks better then the previous generation engines. It at least mimics to a better degree the parts on the engine, though still not what I really want.

[sixpeedreams]

I actually LIKE the way the '14 LT1 looks right now sans its cheap plastic "beauty" covers. And I LOVE the sound of intake "noise". IMO engine covers have NO place on a high performance sports-car. But this is especially true for the Corvette brand which is inexorably linked to and even defined by its engine. Proudly show off that OHV beauty Mr. Juechter!

[sixpeedreams]

Now about engine NVH, here's a couple "think outside the box" crazy ideas: 1) If you must then build sound deadening INTO or AS PART OF the valve covers. For instance, make them out of a more sound deadening material or sandwich of materials or a thicker material. 2) Locate sound deadening UNDER the intake manifold to eliminate unwanted internal engine noise while allowing the intake to sing. 3) Leave a hole in the underhood insulation directly above the intake manifold. Not all "noise" is bad! You've figured that out with the dual-mode exhaust but don't stop there.

[Tomcat]

Originally Posted by Chris Draper

On the slide with the piston and rod, nobody has made mention the words in the brackets. Under the material descriptions for the piston and rod, you will see "(Supercharged Material)", and the tapered rod end description indicates "(Supercharged Type)". I'm thinking these parts are upgraded for supercharged use. The materials and rod end design mentioned and pictured will NOT be part of the "base", non-supercharged LT1.

Since there is a supercharged LT1 (or LT4) coming, maybe it will be part of the initial C7 release, since these features are already being specifically mentioned at the release of the LT1?

Or, am I missing something...

[spd98]

I don't the huge pictures were required lol. It's well known that there will be more than one variant of the LT motor and it's also well known that the performance verson will be supercharged.