Confusing... different size engines with same sump

[MrWideTires]

So I was thinking.. why the heck can engines different sizes have the same sump size?? wouldn't the bigger engine need shorter OCIs??

Two examples:
-My SE-R is a 2.5 and it takes around 4.5 quarts... a Crown Victoria is a 4.6 and it takes around 5 quarts. Shouldn't the Crown Victoria use up its oil faster and need shorter OCIs??

I've heard that variable timing, and timing chains are hard on the oil... so maybe that's why my SE-R is hard on oil and needs a bigger sump??

Other example:
My new beetle is a 2.0 and it takes around 4.2 quarts, my ex-girlfriend's Mitsubishi Endeavor has a 3.8 and it takes around 4.6 quarts!
It takes pretty much the same oil! Shouldn't the bigger engine therefore need shorter OCIs??


Turbo engines excluded... I know turbo engines are much harder on oil, that's why I do 4000 OCIs with synthetic in the STIs.

 

[Nayov]

The CV dosen't work nearly as hard as your Sentra, so that's how they get away with it. Well, that's my take on it.

 

[MrWideTires]

Originally Posted By: Nayov
The CV dosen't work nearly as hard as your Sentra, so that's how they get away with it. Well, that's my take on it.


My guess would be that the engine in the Crown Vic's engine works harder to move the car than my SE-R engine does.

A Crown Vic is relatively slow because it's heavy so the engine has to work to move it... My SE-R has 200hp moving just 2700lbs... I almost never have to go over 3500rpm to move really fast, I would guess my engine has an easier service than a Crown Vic's engine?

 

[RF Overlord]

The CV motor is almost twice the displacement, yet only makes about 40 HP more than your Sentra, so I would say it doesn't work nearly as hard. Lots of CVs see a hard life as a police car, then go another 200,000 miles as a taxi. One Grand Marquis taxi in my town has 435,000 miles on the original motor. No disrespect intended, but I'd like to see a Sentra do that...

Also, since '03 the CV has a 6 qt sump.

Another factor can be oil temp...perhaps the Sentra maintains higher temps than the CV.

 

[Zaedock]

Originally Posted By: MrWideTires

My guess would be that the engine in the Crown Vic's engine works harder to move the car than my SE-R engine does.

A Crown Vic is relatively slow because it's heavy so the engine has to work to move it... My SE-R has 200hp moving just 2700lbs... I almost never have to go over 3500rpm to move really fast, I would guess my engine has an easier service than a Crown Vic's engine?

The Crown Vic and your Sentra have almost identical 0-60 times. Not bad for 2 tons of fun. Your Sentra has 200HP, but only 180lb-ft of torque compared to the Crown Vic's roughly 300. If the CV had 4.10 gears instead of the poopty 2.73's, It wouldn't be much of a race.

 

[MrWideTires]

Originally Posted By: Zaedock
Originally Posted By: MrWideTires

My guess would be that the engine in the Crown Vic's engine works harder to move the car than my SE-R engine does.

A Crown Vic is relatively slow because it's heavy so the engine has to work to move it... My SE-R has 200hp moving just 2700lbs... I almost never have to go over 3500rpm to move really fast, I would guess my engine has an easier service than a Crown Vic's engine?

The Crown Vic and your Sentra have almost identical 0-60 times. Not bad for 2 tons of fun. Your Sentra has 200HP, but only 180lb-ft of torque compared to the Crown Vic's roughly 300. If the CV had 4.10 gears instead of the poopty 2.73's, It wouldn't be much of a race.


I really don't wanna start a battle..
But a Crown Vic does 0-60 in around 9 seconds, my Sentra SE-R does it in under 7 seconds (a little quicker than stock), it has 200hp, and over 200lb-fts of torque (not 180), so my SE-R moves a lot easier than the Crown Vic. Even though the Crown Vic has 265lb-ft of torque.. it's still too heavy so the engine has to work hard and it still has the same 0-60 as a modern Civic.

So technically a Crown Vic should have at least a 7 quart sump...
Unless the 4.6 in the Crown Vic takes it easy because it makes really low hp/liter?

 

[m37charlie]

Severity of oil stress is measured in hp-hr or kw-hr per gram or liter of lube oil. So the oil stress is basically proportional to fuel consumption divided by sump capacity. A passenger car can average 20-40 hp output; a bigger truck can average 60-140 hp; a Class 8 over the road truck could average 200 hp @ 60 mph.
Multiply mpg by sump capacity. The larger number, the smaller the oil stress, the longer the OCI.

Charlie

 

[OVERKILL]

It is a question of power density. The Vic is low in that department. Your Sentra is a fair bit higher. It has to be, a 50HP 4-cylinder no longer cuts it in the economy car world.

This means your Sentra is actually HARDER on oil than the Vic.

Your Sentra's 2.5L makes 80HP/L. The Vic makes 54.35HP/L. To be performing the same amount of work per cylinder the Vic would have to be making 368HP. There is a version of the 5.4L that makes 425HP, which would be right in that ballpark. And it also has a larger sump, as well as an oil cooler.

 

[Zaedock]

Originally Posted By: MrWideTires
I really don't wanna start a battle..
But a Crown Vic does 0-60 in around 9 seconds, my Sentra SE-R does it in under 7 seconds (a little quicker than stock), it has 200hp, and over 200lb-fts of torque (not 180), so my SE-R moves a lot easier than the Crown Vic. Even though the Crown Vic has 265lb-ft of torque.. it's still too heavy so the engine has to work hard and it still has the same 0-60 as a modern Civic.

So technically a Crown Vic should have at least a 7 quart sump...
Unless the 4.6 in the Crown Vic takes it easy because it makes really low hp/liter?

I do not wish to participate in a battle either, but please come to the table with accurate information.

Here's your engine specs right off the Nissan site for a 2010 Sentra SE-R:
QR25DE – 2.5-liter DOHC 16-valve 4-cylinder engine
200 hp @ 6,600 rpm
180 lb-ft of torque @ 5,200 rpm
Compression ratio – 10.5:1


Here are the specs for a 2008 Crown Vic Interceptor

Engine Horsepower (hp @ rpm) Torque (lb.-ft. @ rpm)
4.6L V8 250 @ 5000 297 @ 4000



Given this info and the SE-R's 3,058 lb curb weight (off of Nissan's site), the Crown Vic only has to move an extra 1000 lb's of weight with 117 more lb-ft of torque. It would seem that the 2.5L would need to work harder.

 

[typ901]

Originally Posted By: RF Overlord
The CV motor is almost twice the displacement, yet only makes about 40 HP more than your Sentra, so I would say it doesn't work nearly as hard. Lots of CVs see a hard life as a police car, then go another 200,000 miles as a taxi. One Grand Marquis taxi in my town has 435,000 miles on the original motor. No disrespect intended, but I'd like to see a Sentra do that...

Also, since '03 the CV has a 6 qt sump.

Another factor can be oil temp...perhaps the Sentra maintains higher temps than the CV.



Not sure, but '04-'06 Porsche Cayenne's have a 9qt. sump! and their displacement is 4.5 liters, then enlarged to 4.8 liter displacement, with i assume the same size sump.

 

[MrWideTires]

Originally Posted By: Zaedock
Originally Posted By: MrWideTires
I really don't wanna start a battle..
But a Crown Vic does 0-60 in around 9 seconds, my Sentra SE-R does it in under 7 seconds (a little quicker than stock), it has 200hp, and over 200lb-fts of torque (not 180), so my SE-R moves a lot easier than the Crown Vic. Even though the Crown Vic has 265lb-ft of torque.. it's still too heavy so the engine has to work hard and it still has the same 0-60 as a modern Civic.

So technically a Crown Vic should have at least a 7 quart sump...
Unless the 4.6 in the Crown Vic takes it easy because it makes really low hp/liter?

I do not wish to participate in a battle either, but please come to the table with accurate information.

Here's your engine specs right off the Nissan site for a 2010 Sentra SE-R:
QR25DE – 2.5-liter DOHC 16-valve 4-cylinder engine
200 hp @ 6,600 rpm
180 lb-ft of torque @ 5,200 rpm
Compression ratio – 10.5:1


Here are the specs for a 2008 Crown Vic Interceptor

Engine Horsepower (hp @ rpm) Torque (lb.-ft. @ rpm)
4.6L V8 250 @ 5000 297 @ 4000



Given this info and the SE-R's 3,058 lb curb weight (off of Nissan's site), the Crown Vic only has to move an extra 1000 lb's of weight with 117 more lb-ft of torque. It would seem that the 2.5L would need to work harder.



Mine is not a 2010... it's a modified 2004. Which weights less... somewhere around 2750lbs. and it reaches its peak horsepower and torque at lower rpm

 

[joflewbyu2]

MrWideTires has enough on his plate. this is info on the 04 SE-R Spec V. I remember them! They had SUPER SHORT GEAR RATIO that need 3rd gear to hit 60 mph. That and a CV would be very comparable to 100 mph - approx 23 seconds.


Right from Wiki-pedia:


Manufacturing, design, and assembly flaws

The QR25DE sold in the United States has been subject to a significant number of problems in its short lifetime. A variety of mechanical flaws have led to numerous technical service bulletins, recalls, repairs, and outright engine replacements.

* Vehicles with the QR25DE may ingest material from a damaged pre-catalyst resulting in increased oil consumption.[7]
* Power valve screws in the intake manifold may become loose and result in unstable idling or power loss.[8]
* In June 2006, it came to Nissan's attention that approximately 85,000 Altimas and 2,000 Sentra SE-Rs equipped with the QR25DE and built between January and May 2006 may experience unusually high oil consumption. This can lead to premature engine failure and possibly a fire. While Nissan investigates the problem, owners of the affected vehicles are being advised to check their oil frequently (every 700 mi (1,100 km) [1127 km]), and dealers have been instructed to place the affected vehicles on sales hold.[9]

[edit] Stated versus observed power

In addition to the physical problems suffered by the QR25DE, Nissan's official stated power and torque numbers seem to disconnect from power measurements taken by the general public. Though rated for 175 hp (130 kW) and 180 ft·lbf (240 N·m) of torque in the Nissan Altima and Sentra SE-R Spec-V, the actual power of the engine may be significantly lower. Multiple dynamometer readings performed by a range of people in an assortment of cars over several years have shown that the engine more than likely produces ~160 hp and ~170 ft·lbf of torque. Parasitic loss alone seems an unlikely candidate for the discrepancy as automatic transmission loss would be approximately 28% and manual transmission loss 19%.[10][11]

However, engine dyno tests performed by Brian Crower, a respected aftermarket parts supplier, shows this engine does indeed perform very close to the advertised numbers. The high weight of the Helical Limited Slip differential which is in many models with this engine, and the very heavy dual mass flywheel likely account for the losses on traditional chassis dynos.

 

[MrWideTires]

^^people keep missing this car is not stock

 

[JohnBrowning]

I knew a guy with a Nissan Sentra with 500,000 miles on it. He used it for Pizza Delivery and as a daily driver. I have to admit it is the only one I have seen with that many miles but I know it happens. Dino 3000 mile oil changes where the norm for him. I also know he was a sucker for every oil additive that made it on to TV or into the Parts Stores in town.

 

[joflewbyu2]

Originally Posted By: MrWideTires
^^people keep missing this car is not stock
Tell us what internally has been done. Don't even try exhaust as most of the time the reduction of back pressure reduces low end torque and hurts performance. Even short ram air intakes hurt performance as they suck hot air that is less dense and more turbulent under the hood which plays havac on the air flow sensor.

 

[JohnBrowning]

Usualy V8's in non-performance applications are grossly under tuned so they are not working hard if you look at the power density of the engine. IN a large car torque is what makes it move well from a dead stop but HP numbers are what Marketing advetises. If you have a good torque from idle up to 2800 then 99% of Americans are happy in non-performance applications this is why you seldom see any detroit iron with engines that rev past 6500 and often as low as 5400 RPM's. Most non-performance V8's you see HP and Torque number cross at around 2500 RPM's or close to that. On the HWY that CV is probably turning 1800 RPM's going 70-80MPH while your Nissan is going to be turning 3000 RPM's to go just as fast. So trust me when I say that the Nissan is much harder on oil....Now if the Crown Vic made as much HP and TQ per cubic inch as your little Nissan engine turn as many RPM's as a norm say cruising along the AutoStrada at 160MPH that little sump would have to be much bigger even if it ran something exotic like Redline if they wanted to have a decent OCI!