alfadriver wrote:
Klayfish wrote:
All I can tell you is having sampled both is this...
Put two identical cars side by side. One has a small boosted motor, one has displacement. Both make identical hp and tq numbers. I can tell you which one I'm taking. Displacement every day of the week and twice on Sunday.
I don't hate small boosters, but definitely prefer big 'uns. Hmmm...kinda like another preference I have...
Back in 2010, I thought that truck buyers thought exactly like you do. Moreso that truck buyers would never want a turbo V6 to replace a V8.
Now we are seeing that there's a really big chunk of truck buyers who are getting the turbo V6s instead of V8s.
I had to change my mind about buyers.
Certainly, there are buyers like you. But not nearly as many as I thought.
But, bare in mind Ford's V-8 mod motors have always sucked ass in trucks.
In reply to Appleseed:
But they still sold in very high numbers, and many had the impression of the beefy V8 is the correct truck engine.
I have a different impression of many customers.
alfadriver wrote:
In reply to Appleseed:
But they still sold in very high numbers, and many had the impression of the beefy V8 is the correct truck engine.
I have a different impression of many customers.
Yep. I facepalm every time I see someone take a 5.0 over a 3.5 EB in a new F-150 because they "have to have a V8".
Bobzilla wrote:
In reply to oldopelguy:
That's because the entire car is a pile of E36 M3. But because it gets 50mpg.
This from a guy that drives a Kia Rio??
The subject original post appears to be lost on Honda.
rslifkin wrote:
alfadriver wrote:
In reply to Appleseed:
But they still sold in very high numbers, and many had the impression of the beefy V8 is the correct truck engine.
I have a different impression of many customers.
Yep. I facepalm every time I see someone take a 5.0 over a 3.5 EB in a new F-150 because they "have to have a V8".
I've stopped that a long time ago. A large portion of car buying is an emotional choice. So...
If it was more toward logic, few would ever buy a truck to commute with, let alone a large 5 seat sedan.
Alas, emotion is a big part. So as long as they keep sending me money, I'm fine.
alfadriver wrote: BUT- there is some movement in the industry to change the whole fuel supply to premium. That, and reducing the huge variety of regional blends, will lower the cost of gas (relative to the barrel cost).
What are the chances of that happening with California and other states pretty much only allowing watered down piss to be sold? My Porsche says min93 RON+MON / 2 and all I saw at all in Colorado this summer was 91 max, same in Cali when I was last there.
Note. I'm sure in both Cali and Colorado you can get 93 in many places, but I didn't see it once in mainstream stations I stopped at.
In reply to Adrian_Thompson:
If the whole nation goes, very high.
California reduced the choices to get a better hold of the blends available, which can reduce the emissions.
Colorado is a different story- at that altitude, for NA cars, the octane requirement goes down quite a bit. So premium in high areas is generally lower than at sea level.
alfadriver wrote:
Colorado is a different story- at that altitude, for NA cars, the octane requirement goes down quite a bit. So premium in high areas is generally lower than at sea level.
Yep. I remember being out in the TX pandhandle/NM and sometimes only seeing 88 as the high octane choice.
alfadriver wrote:
Colorado is a different story- at that altitude, for NA cars, the octane requirement goes down quite a bit. So premium in high areas is generally lower than at sea level.
This makes sense for carb-ed applications, but in some EFI situations, it doesn't.
In something like my Jeep where the timing curve is based on MAP vs RPM, altitude won't reduce octane requirements. Thinner air just means it'll stay further to the left on the timing table at WOT, so it'll be running more timing than it would be at sea level (effectively never pulling out all of the "vacuum advance").
So at higher altitude, WOT would give the same fueling and timing as somewhat less than WOT would at sea level. Which means if the tune is pushed hard enough to need 93 at sea level at times other than WOT, you'll still need 93 at high altitude.
In reply to rslifkin:
The fact that your WOT pressure is reduced is exactly why the octane requirement goes down.
Turbos are where that starts to fall apart. But even for those, the octane requirement goes down a little due to lower exhaust back pressure AND that the turbo is less efficient.
alfadriver wrote:
In reply to rslifkin:
The fact that your WOT pressure is reduced is exactly why the octane requirement goes down.
That would make sense if the timing at WOT was always the same. But if we assume that we're at WOT and 4000 RPM, at sea level with a manifold pressure of 14.7 psi (absolute pressure), we'd be looking at about 32 degrees of timing. Now if we're at higher altitude and the manifold pressure is only 12 psi, we'd have something like 37 degrees of timing. Because of that, isn't it entirely possible to still be just as close to the edge of detonation and still need just as much octane?
But it's more likely that you will knock at 14.7 psi than 12 psi, even given the spark timing.
I've not seen a system that doesn't break down spark into best spark and knocking spark. And those come together at pretty high loads for most engines. The fact that peak intake pressure goes down has a big effect.
That, and the lower exhaust pressure also has a big effect on breathing. Both contribute a lot to lower knock.
The only beef I have with my 1.4t in the Cruze is that, with the 6 speed manual, 1st gear is almost unusable above 3k rpm - once the boost comes on (as little as the fist sized turbo actually makes), the STEEEEP 1st gearing creates a linear torque curve that pulls your fillings out...for about .75 seconds until the turbo runs out of breath at 6500 rpm. But, then, when you shift, you leave a cheek print in the windshield when the front drops as the torque falls off when you press in the clutch. Second - sixth are geared pretty well, slightly too tall in fact. Starting from second is doable, but your clutch will hate you for it - the 1.4 on its own doesnt have enough to offer if youre off boost - so, you need the tall 1st to accelerate from a stop, but dont try to do it fast, or youll flip the car over. Dont try to start in second because you dont have enough powah. Its just a no-win "lesser of 2 evils" decision that Chevy ended up having to make in the "HP, Economy, Driveability: Pick 2" debate
As some said, If you want performance buy a performance car.
The Cruze, like many are built for economy.
I think when the idea of TURBO come up, we tend to think performance.
WRT octane - overall, it drops west of the Rockies. There's no 93 in Colorado. Generally speaking gas gets crappier as you go west. Texas isn't west, it's south
My brother in law sold his big diesel Ford and replaced it with an Ecoboost F150. I give him a hard time about finally going with a turbo six, like all the Cummins trucks in the family
This is why I actually like my Highlander hybrid. 3.3L V6 and 2 electric motors. Ample poke when I want it and can crawl around in traffic with the engine off entirely. Boring, but efficient.
Found these numbers from Forbes:
Horsepower: gas: 208 hp at 5,600 rpm; electric: 167 hp at 0 to 4,500 rpm
Torque: gas: 212 pound-feet at 4,400 rpm; electric: 247 pound-feet at 0 to 1,500 rpm
codrus
SuperDork
10/18/16 11:51 a.m.
alfadriver wrote:
California reduced the choices to get a better hold of the blends available, which can reduce the emissions.
California has "boutique gas". The blend requirements are very specialized for very small areas, meaning that there are very few refineries actually making it and that pushes prices up. The reason we only get 91 is that they're trying to cut costs in any way possible to try to make up for that. There's actually no legislated maximum on the octane available.
So, yes, it's government regulation that's at fault, but not because they're specifically trying to limit the octane.
jharry3
New Reader
10/18/16 11:55 a.m.
Huckleberry wrote:
Why doesn't anyone ever solve this problem with dramatically less weight to move around?
Safety regulations. Heavier cars decelerate at a slower rate. Lighter ones tend to stop more quickly. Do a government crash test in a Lotus 7 and its deceleration rates will gobsmack the crash test dummy.
You need more steel to make crumple zones that decrease deceleration.
Keith Tanner wrote:
WRT octane - overall, it drops west of the Rockies. There's no 93 in Colorado. Generally speaking gas gets crappier as you go west. Texas isn't west, it's south
I mentioned the TX panhandle and NM. Being that I live EAST of Hallett, OK, both locations are definitely WEST of where I am located.
The TX panhandle and NM are really part of Mexico I'm guessing those were very rural stations.
Keith Tanner wrote:
The TX panhandle and NM are really part of Mexico I'm guessing those were very rural stations.
Yes, the small town where the hunting lodge and wedding was.......there was one gas pump, no station, no awning, and you had to have a special card to access the fuel.
I think the town just barely had a Post Office. We had to stay 45 minutes away to even get a hotel room.
This is an interesting trend isn't it. Makes me think of the 90s Japanese cars and the pre and post-bubble vehicles. With Toyota and Nissan brining 6 cylinder twin turbos back and even Ford and GM jumping on... interesting times are coming.
The bubble era cars had wild electronics and interiors, supercar suspensions, and have advanced engines that either make very high power NA or turbo. For example the Cosmo’s touch screen GPS, the 7g Galant’s electronic adjustable suspension, the FD RX7s light weight with “280hp” wankel, the Evo’s active yaw control, civic type-r’s vtech with lift and double wishbones, etc. Twin turbo i6 cars and v6 cars were common. SOME of this continues into around 2002 but it gradually decreases after the bubble bursts. For example the post-bubble 2zz-ge engine and the Celica GT-S.
It seems the 90s car is making a come back. Those electronic wonders in special Japanese cars from back then are in everything now. They are bringing big displacement (3.0l and higher v6) with turbos again. On top of that the special cars like this are the same price they were in 1996. $60k is what a Supra cost then. This new infiniti q coupe with 400hp twin turbo is the same price. Now even things like the Civic Type-R is coming
The post-bubble japanese cars all went cheap and ditched turbos, you had some high revving engines like the 2ZZ and all of that.
The only problem is that these cars are still missing something compared to the equivalent vehicles back then. Like reviews on the infiniti Q cars all mention this, especially harping on the non existent steering feel.
I'm hoping this doesn't mean a $60k Fairlady Z is coming. I would like to see a twin turbo V6 in a $35k Z.
Shaun
HalfDork
10/18/16 2:56 p.m.
alfadriver wrote:
D2W wrote:
alfadriver wrote:
tuna55 wrote:
Alfadriver:
Has there ever been a real study of an understressed low RPM, low power large displacement as compared to a high strung turbo small displacement engine within your walls?
We model performance on our stuff like crazy. I can only imagine that you guys do too.
My instinct tells me that they would be very close to each other in most real world reasonable scenarios (no 50CC turbo 2s compared with 9 liter V10s).
The hardest of the hard part isn't making a lot of power, it's making very little efficiently.
In terms of power and torque, many of our small displacement turbos are better than their "equal" normally aspirated- mostly because boost means low end torque that is nice to drive.
But most of use normally use 5-30 hp on a normal day. That's it. This board will generally use more for honing, but if you just are doing traffic- 5-30 is all you really use.
And small engines do that better.
So the trick is making a small engine act like a big one (boosting) or a big engine act like a small one (turning cylinders totally off via valvetrain).
The discussion you speak of has been going on for years- trying to find the sweetspot of weight to displacement. Sometimes they do it pretty well, sometimes not.
5-30hp is all most people use? To me this begs the question why isn't one of the automakers building this car? A small commuter with 30 hp that gets 80 to 100 mpg. Nobody here would want it, but I know there is a lot of people out there that would.
Marketing.
35 years ago, most cars had 0-60 times in the ~10-12 second range. Now they can do that in 6-8 seconds. Why? Because.
My CRX HF had all of 65 hp. And I never had a problem with speed and power keeping up.
Next time you get on a freeway, pay attention to those around you- they are still accelerating at 80's times, and not using the power of the engine.
BTW, I'm not exaggerating in terms of the power used- most people accelerate so gently getting on the freeway, they don't use more than 30 hp. Which allows early shifts to low speeds/high torques.
Truck can add 10-20 hp in their days.
Heck, we have HUGE tow abilities, and people still drive trucks empty and one passenger.
Between the fact that people buy potential over what they need, and increased safety requirements- that's why fuel economy has crept up so very slowly (as a fleet).
I always find it funny to enter a freeway with that BMW guy who just got the car for image. They crawl so slowly that I can keep up really easy with my 1.6l Fiesta.
I think the slow on-ramp velocity tendency has become worse. I leave huge gaps and accelerate hard late if there is an entering car in front of me now in order to enter at freeway speed and still leave a gap for vehicles in the slow lane. NVH sucess? Gizmo overload? Aging population? Air bags and seat belts? All that and more? 'Out west' semi's have increasingly, errr pretty much- made the number 2 lane home in urban areas to avoid clueless entering vehicles. A very smart person in tech said to me that self driving cars are becoming necessary because (other!) humans are abdicating piloting responsibility regardless of danger.