: The new Corvette is going to make only 450HP but will have better fuel economy.



mrkool
10-24-12, 02:28 PM
What do you guys think the new CTS-V will be based on the LT1 engine?

http://www.autoweek.com/article/20121024/CARNEWS/121029932?utm_source=reddit&utm_medium=social&utm_campaign=social

M5eater
10-24-12, 02:41 PM
looks like they finnaly threw DoD, and VCT on there too.. ugh.


This thing needs to make 30mpg..

although, 50ft/lbs more torque sounds like a big improvement

Xaqtly
10-24-12, 02:41 PM
Well it says "at least" 450 HP. And the LS3 only makes 430, so I'd say that's pretty good. It also makes more power and more torque while getting better MPG, I like that too. Direct injection, cylinder deactivation and continuously variable cam timing are all good things in my book. Also worth noting, the LT1 has an 11.5:1 compression ratio, so any car that has a forced induction version of that engine will, I'm assuming, use different pistons to get a lower compression ratio. The LSA has 9.1:1 compression.

Frankly it sounds like this engine will be a blast in a new C7. More torque everywhere, higher compression and higher redline, should be considerably better MPG too. And apparently the 7-speed manual is coming too, and that 7th gear combined with this engine, with cylinder deactivation and direct injection, will produce surprisingly good MPG I bet. That's impressive considering the extra power and torque it's making.

A lower compression version with a supercharger combined with the 7 speed manual in the gen 3 CTS-V will almost undoubtedly bring it into the high 20s, maybe 30 MPG highway range, partially because of the lighter weight and better Cd of the next gen CTS. It should have all the badassery of the current LSA, maybe even more, while being much, much better on gas when it's not being thrashed. Sounds like a winning combination to me.

M5eater
10-24-12, 02:43 PM
Direct injection, cylinder deactivation and continuously variable cam timing are all good things in my book.
I'm not convinced.

The DoD systems in curren Gen IV's do not like sustained RPM's, they do not like gobs of power, and they're always swapped for non DoD systems.

D/I is another hurrdle that present's it's own problems, so does VCT.

They've put on a lot of technology that's going to make it harder(or at least more expensive) to make power with this engine, and the corvette is one of the most modified vehicles in the country..

Xaqtly
10-24-12, 03:08 PM
I think you'll be surprised at how good it is. This isn't new technology in the context of the entire auto industry, I mean variable cam timing has been around for at least 10 years now and DI has been around even longer. And if the DoD system weren't able to handle power or run at sustained RPMs, they wouldn't be putting it into a Vette. I really don't think we're going to see any actual performance or modding drawbacks from these changes.

Jinx
10-24-12, 03:12 PM
They've put on a lot of technology that's going to make it harder(or at least more expensive) to make power with this engine, and the corvette is one of the most modified vehicles in the country..

Hot-rodders have been brow-furrowing over new technology forever. Hot-rodding continues.

larry arizona
10-24-12, 03:16 PM
Well aftermarket suppliers are going to be pissed and busy. Nothing is shared from the current LS engines. Top end and bottom end are all new. Sounds like mods will be few are long in coming.

M5eater
10-24-12, 03:22 PM
I think you'll be surprised at how good it is. This isn't new technology in the context of the entire auto industry, I mean variable cam timing has been around for at least 10 years now and DI has been around even longer. And if the DoD system weren't able to handle power or run at sustained RPMs, they wouldn't be putting it into a Vette. I really don't think we're going to see any actual performance or modding drawbacks from these changes.

That has diddly sqat to do with the fact that the DoD systems in use now are fragile, the VCT units in all pushrod V8's are swapped for non VCT units in high power vehicles, and D/I injectors are hugely expenisve, the fuel pressure problems plauge a wide array of automanfuactures, and it's pretty difficult to modify the system at any one point without incurring huge costs.

None of this is good for the aftermarket portion of the corvette, all of this has been tried and found inferior or lacking in the platforms that exist and use this technology.

larry arizona
10-24-12, 03:32 PM
Agree with the above, this does not bode well for cam upgrades, Tuning, fuel delivery aka bigger injectors, heads etc....... maybe this is GM's way of shutting down the aftermarket.This will be interesting. I will keep my V2 LSA for a long time while its figured out.

smackdownCTSV
10-24-12, 03:58 PM
What's with the upside down throttle body?

DRL650
10-24-12, 06:55 PM
■LT1 is the first OHV engine with Direct Injection. I am not impressed at all. I have had several C6s over the last 6 years and was really getting excited for the new powertrain but not after reading this. Maybe the Grand Sport and Z06 will come with an lt2 and 525 & 600hp? lol.And please remove the DOD system leave that for the malibu..

quikag
10-24-12, 07:46 PM
It is possible the DOD system doesn't make it on the Vette. Actually, I hope that's the case if for no other reason than a lame exhaust note at light, cruising throttle with an aftermarket exhaust.

JFJr
10-24-12, 08:03 PM
It is possible the DOD system doesn't make it on the Vette. Actually, I hope that's the case if for no other reason than a lame exhaust note at light, cruising throttle with an aftermarket exhaust.

I remember the DOD from the mid-80's Cadillacs. Please don't put that crap in any performance engine ever again. We don't need it in a low-production high performance car.

Jud

SoonerSpeedFreak
10-24-12, 08:46 PM
This is the BASE vette. More horsepower. More torque. Faster 0 to 60 time. Better fuel economy. Sounds good to me. The vette's and V's will continue to get more power, loose weight, better fuel economy, and become faster. Have faith.

M5eater
10-24-12, 09:25 PM
■LT1 is the first OHV engine with Direct Injection. I am not impressed at all. I have had several C6s over the last 6 years and was really getting excited for the new powertrain but not after reading this. Maybe the Grand Sport and Z06 will come with an lt2 and 525 & 600hp? lol.And please remove the DOD system leave that for the malibu..
Ehh, I think it's generationally a fairly decent leap ahead.

+20HP and +50 ft/lbs, with better fuel economy is pretty good out of the same displacement. This is fundamentally the exact same engine as the LS3. GM just keeps polishing the 2V combustion chamber, gets the fuel burn a little better and the VCT helps a lot.

The only problem I have is they drastically increased complexity, which realistically is inevitable, but it doesn't mean I can't complain about it.

The thing that will make it a good or bad compromise will be what city/highway figures the vette pulls. If it manages 18-20 city and 29-30 highway, I think it would have been worth it.

hulksdaddy
10-24-12, 09:49 PM
I got 30 mpg highway driving in my 2008 Z06. How much better can it get?

Jinx
10-25-12, 12:12 AM
Don't want cylinder deactivation? Buy a manual transmission. Problem solved.

I don't think anybody's done cylinder deactivation with a manual transmission yet, and I doubt Corvette will be the first to try it.

Kmajecki
10-25-12, 12:46 AM
Hot-rodders have been brow-furrowing over new technology forever. Hot-rodding continues.

Fuel injection is the devil! Its going to kill hot rodding forever!!!!

M5eater
10-25-12, 09:06 AM
Fuel injection is the devil! Its going to kill hot rodding forever!!!!

in a lot of ways, it did.

You can't just throw on a new carb and tune it a bit with a screwdriver anymore.

You need to go pay someone else to hook up a computer and get a tune, and that easily costs as much as or more than a new carb, and then you might need bigger injectors, possible a new rail, and associated business with FI . Then you need to ask yourself if you trust this person to not blow up your engine.

The tradeoff was that complexity increased but so did potential. They gave it F/I but that's all, you can sneeze on an LS and it'll make power, they were still using relatively simple and low pressure systems.

There are a couple of new elements at work here, VCT, DoD, 2000+PSI fuel pressures and new holes in the combustion chamber on the block.

Every D/I platform I've witnessed has had problems making power with D/I in some way.

Be that carbon build-up on the intake valves, the fact that aftermarket solutions to 2000PSI fuel pumps is zero, high failure rates, injector problems, or out-right inadequate systems necessitating thousands of dollars for upgrades on the pump.

There is a reason why a rebuilt OE HPFP for something as common as say--- a 2.0TFSI is $1100.

http://www.goapr.com/products/fsi_fuel_pump.html

Why N54 owners dump their 335i's worring about the time-bomb in their fuel tank(I think they're on rev #6 without a resolution to their high failure rate)

complexity has increased again, but potential has taken a dive off a cliff, and costs have skyrocketed.



I got 30 mpg highway driving in my 2008 Z06. How much better can it get?
The next ZR1 will avoid the GG tax entirely, just like the GT500 does now, and I've heard all kinds of crazy claims about 30mpg Z's and what-not.

That's all fine and dandy.. the EPA rattings take that into their caculations if you read the fine print but, it's not the 'nominal' number. When I can get 30 combined on the hills and crappy roads here in VA in a 550HP Z, and gas is $4-5 I'll be estatic.

Right now though, in my 4100lb brick, I get ~ 13-16, and that sucks.

You have to also remember, they sell a crap-ton more SUV's with these engines than they do Corvettes.

thebigjimsho
10-26-12, 12:10 AM
Much ado about nothing.