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Blumlein 88

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It is actually easier (though not often enough done) to get a good weight distribution for a fast road car with a front engine than with mid.
I suspect this car is to homologate this layout for racing in the very competitive production car series. Will winning its class at Le Mans etc add to sales? I doubt it so, as you write, this may be much less suited to current owners than the existing one.
The only Corvette I have driven was a ZR1 and I loved it, though the interior was a bit low-rent and rattly for the price (here in the UK)

I think one of the better short descriptions of recent Corvettes was when someone said, "Performance of a car costing twice as much, build quality of a car costing half as much". I do think the interiors have been the weak point.

The Corvettes have had 49 front/ 51 rear weight distribution since the 1970s. A few engine transmission options alter that a percent either way. I would think a mid-engine car has a lower polar moment of inertia. Which I am supposing is better for racing though whether that is true you'd know that much better than I.
 

Tip

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I think one of the better short descriptions of recent Corvettes was when someone said, "Performance of a car costing twice as much, build quality of a car costing half as much". I do think the interiors have been the weak point.
When I bought my C5 Corvette I also was looking at the Boxster and the M3. The C5 was the only one where the steering wheel was directly in front of the driver's seat, plus it had a heads-up display; the others had the steering wheel a few inches off-center (I hate that!) The C5 also had a huge rear storage space under the hatch where I could carry my expensive bicycle(s). So while the interior was cheap, it was more functional. After all, I've bought two cheap-but-functional WRXs ;^)

I'm still trying to decide on my next car. I'm leaning towards the Genesis G70 with the twin-turbo V6 and AWD or maybe the BMW M240ix. Any opinions?
 

JJB70

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The idea of a mid-engine Corvette just doesn't seem right. There is something about a big engine front engine muscle car that just seems more appealing to me than a mid-engine alternative.
 

Ron Texas

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I think one of the better short descriptions of recent Corvettes was when someone said, "Performance of a car costing twice as much, build quality of a car costing half as much". I do think the interiors have been the weak point.

Corvette interiors from the perspective of luxury are about the same as my Camaro SS, which is much better than a Malibu. Build quality on recent Chevys is extremely high, even if the plastic and switches aren't as pretty as a German luxury car.
 

Blumlein 88

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Corvette interiors from the perspective of luxury are about the same as my Camaro SS, which is much better than a Malibu. Build quality on recent Chevys is extremely high, even if the plastic and switches aren't as pretty as a German luxury car.

Well I've not spent time in the newer Camaro or the C7, but felt it applied to the C5 and C6. There wasn't anything really wrong with the interiors. They were mostly the better parts from other GM cars. But HVAC switches, turn signals, wiper, radio and light controls the feel of it all weren't what you'd expect from an expensive car. Door handles and the quality of the plastic seemed a bit down vs other cars. Now layout of the instrument panel and the HUD display were fine in my opinion. And it was part of the trade off vs something really expensive.
 

Ron Texas

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@Blumlein 88 I used to have a C4 with a manual transmission. It's rated HP of 300 was way conservative, it was too fast for that. The main drawback of the car was the chassis was not stiff enough. The C5, owners tell me was a big improvement in that area. I actually think the C6 is a better looking car than the C7. I prefer curves to the exploding knife factory look.

The dash in my Camaro is nice and so is the HUD, although I don't know if I really need it. The car is so fast that it is more about what it can do than what you actually get to do. Kind of nuts, but that's how it is.
 

Blumlein 88

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@Blumlein 88 I used to have a C4 with a manual transmission. It's rated HP of 300 was way conservative, it was too fast for that. The main drawback of the car was the chassis was not stiff enough. The C5, owners tell me was a big improvement in that area. I actually think the C6 is a better looking car than the C7. I prefer curves to the exploding knife factory look.

The dash in my Camaro is nice and so is the HUD, although I don't know if I really need it. The car is so fast that it is more about what it can do than what you actually get to do. Kind of nuts, but that's how it is.

Did you ever hear why the C4 was so flexible? I've driven a few and as they get more miles that get more squeaks and rattles noticeably. The design team for the C4 was getting the final round of sign offs from the higher ups, and some upper level managers insisted it be a targa top. Some marketings wizards said the Porsche with targa was more desirable and the C4 would have that. It was a last minute blind side. The chief engineer McLellen told them the body needed the top for stiffness. They ended up being told you do it with a targa top or we won't do it at all. We've been considering killing it altogether and without the targa it is dead. He told them there was no time to make the design right, and they said fine, you have 3 months or its over. And plan on a convertible within 2 years. That is why they have the big square beams at the bottom of the door openings. Only quick way to make it adequately stiff to even manufacture with a top that comes off.

That is also why the C5 and later were built on a backbone frame. So it could have the top come off, or be a convertible and be fairly stiff whatever the crazy marketing people forced on them. The C5s are markedly stiffer than the C4 which is too flexible. My father has a Indy pace car convertible C4 right now. His is a 1995 model.
 
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Ron Texas

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@Blumlein 88 It drove a lot better with the top in place. It was a major effort to get the top off. It had faults, but for a 1990's car, it was "sick" as they say.
 

Tip

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That is also why the C5 and later were built on a backbone frame. So it could have the top come off, or be a convertible and be fairly stiff whatever the crazy marketing people forced on them. The C5s are markedly stiffer than the C4 which is too flexible. My father has a Indy pace car convertible C4 right now. His is a 1995 model.
That's true, but the C5 still wasn't all that stiff. The Z06 version of the C5 had a magnesium-reinforced fixed roof to make it stiffer. Side note: I worked at the same company and lived in the same neighborhood as Barb Hamilton-Advey (first woman in drag racing to receive an NHRA license for driving supercharged cars and the first woman to be inducted in the NHRA Hall of Fame). She had a C4 when I bought my C5. Then she bought a Z06 C5. We'd "race" each other on the drive home from work.
 

Frank Dernie

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I would think a mid-engine car has a lower polar moment of inertia. Which I am supposing is better for racing though whether that is true you'd know that much better than I.
Overall low polar moment is no real benefit on a F1 car. If one measures the maximum rotational acceleration the forces involved are tiny compared to cornering forces (about 1%) maybe on cars with much less grip it is more important but I have never looked into it since I don't have rotational acceleration data.
Low polar moment and low unsprung mass aren't worth chasing if it compromises something else.
 

Juhazi

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Mid-engine Peugeot 205 T16 was perhaps the best rally car ever. It turned and jumped like no other! Vatanen, Kankkunen, Salonen, Saby reigned over Audi Quattros, Lancias etc. in group B haydays.


 
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JJB70

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Interior quality is a funny old thing. At a rational level it may be silly but I find that nicely weighted and damped controls to be hugely satisfying. A few years ago I was looking for a small car and looked at the Toyota Yaris which I thought was the best car in its class at the time in objective terms but I couldn't bring myself to buy it because of the crappy interior feel. I find that in many ways Audi's are really not that good but one thing that they know how to do is how to make a nice interior. I have owned a couple of Audi's, neither was (or is, my current car is an Audi) brilliant in dynamic terms but they did/do feel nice inside.
 

RayDunzl

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A little update on the Camry after a trip to Corsicana Texas...

Overall MPG = 35.8 for 5900 miles.

Highest tank mileage and range - 55-65 puttering along back roads in South Texas and Louisiana - 43.4mpg, 600.5 miles on the tank, with an indicated 57 miles to empty (and estimated 94 miles to really empty)

75-80mph Interstate - 39.1mpg

Blue -tank mpg, Orange - simple average

1562947218984.png
 
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Sal1950

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A little update on the Camry after a trip to Corsicana Texas...
My God, you keep data records on your car MPG too. We got to work on your obsessive nature Ray. ;)
 

Blumlein 88

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Ray just needs to adapt some Pulse and Glide driving techniques. Should be able to boost his mileage by 40-50% if he does that. Easily into the 60 mpg range.
 

Sal1950

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milw50717

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Vauxhall Cavalier - Peugeot 205 GTi - Ford Sierra XR4x4 (with some Turbo Technics magic under the bonnet/hood) - a really long time with no car (AKA city dweller) - Nissan Maxima -> Honda Odyssey minivan - Honda Pilot SUV - Porsche Cayman S - Jeep Wrangler JK - Ford Fusion Hybrid - Toyota Prius V - Honda Accord Hybrid.

I started off well, had a hiccup with the baby carrier, hung up the Piston Heads membership and pretty much it was all downhill from there. Of all the cars, I would have to say that the Jeep is the one that I miss. Simple basic engineering, as aerodynamic as a brick, with a low top speed and horrendous fuel economy, but an iconic vehicle for me.
 

Blumlein 88

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Huh? Does that have anything to do with the hp/weight ratio?
Pulse and glide is a driving technique used to get all those unbelievable gas mileage records. You can get about 50-100% more than whatever your vehicle gets if you do this.

Hp/weight ratio tie ins? If you have too low a ratio, it will hamper your use of this technique because it will prevent you using the engine in its most efficient range.

Here is the technique as I used it. Accelerate at about 85% wide open throttle up to 45 mph, throw it in neutral and coast to 15 mph and repeat or if needed stop. If your hp/wt ratio is too low you'll either spin the tires or not be able to use 85% throttle. Using a nearly wide open throttle is key to max efficiency. The technique can be adapted to other speeds and conditions while still paying out big gains in mpg.

A decade or so ago when driving a small pickup to work, using this technique I managed to go from 21-22 mpg to 39 mpg. Did this over 3 consecutive tanks. And one other tank was almost 38 mpg while I was fine tuning how to do it. I was allowing the engine to idle while coasting because it was summer and I wanted AC. Otherwise I'd have made it over 40 mpg.

So I don't know with your truck Sal. You may have to accelerate to 60 mph and coast down to only 45 mph before starting the cycle over. :)
 

Sal1950

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Here is the technique as I used it. Accelerate at about 85% wide open throttle up to 45 mph, throw it in neutral and coast to 15 mph and repeat or if needed stop.
Humm, really. That just doesn't add up as a fuel saving method but I'll take your word for it.
Living in the inner city doesn't really lend itself to a trial.
 

Blumlein 88

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Humm, really. That just doesn't add up as a fuel saving method but I'll take your word for it.
Living in the inner city doesn't really lend itself to a trial.
A gasoline engine is most thermally efficient wide open. Actually that is part of why a diesel is good, they are always wide open no throttle.

So one curve is decreasing efficiency as less engine power is used.

The opposite curve is aerodynamic drag. Twice as fast is 4 times the drag and 8 times the power. Going slower reduces this a lot.

So the two curves intersect for most efficiency somewhere near 45 mph for most gasoline engine vehicles. Go faster and aero drag goes up much more quickly than engine efficiency. Go slower and aero at 45 mph is already negligible so engine efficiency drops more than you gain from lowering aero drag because friction drag is predominate at the lower speeds.

Pulse up to 45 mph, you've used the engine at its most efficient way, used nearly none of the energy overcoming aero drag, and built up kinetic energy in exchange for the fuel used. Coast, aero is pretty neglible, and you'll bleed off the kinetic energy overcoming friction which you purchased with the least amount of fuel. It is the least energy intensive way to drive for an IC engine.

Most gasoline vehicles get best mileage on level ground at constant speed somewhere between 40 and 50 mph. Most get about the same mileage at 35 mph as they do at 70 or 75 mph.

I was lucky trying this going to and from work. There were 3 reasonably equal routes. The shortest was about 4 minutes longer because it had stop signs every 3 blocks or so. These turned out to be almost perfect for P&G driving. I could zip up to 45 mph and coast down doing about 15 mph or less when I needed to stop. There was one section I could get in 2 P&G cycles. These streets had little traffic and the speed was safe so I wasn't bugging anyone with the odd driving style. If I could have done this without the stop signs the mileage would have gone up a few more MPG.

Now this wouldn't be necessary with an electric car. Slower is simply better. You likely gain very little below 30 mph.
 
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