: 4.6 liters 300hp... 2.0 liters 200hp



majax
07-30-04, 04:40 AM
My brother is a high performance car person and really into Nissans etc. He talks about how japanies engines can achieve around 100hp per 1,000cc(1 liter). So I was talking to him about the Northstar and about how many liters it is and how much power and basically he said its not a good engine since its only achieveing 300hp from about 4,600 cc. He was also saying thats how American engines get their power by just being bigger. That the engines that get around 100 per liter are better built and stronger. Cause if im not mistaken a Northstar couldn't handle 460hp. So what does this all mean, is the Northstar a UN impresive engine? Is the Northstar poorly made and not strong enough to handle 100hp per liter? Also, why didnt cadillac make the Northstar around 100hp per liter(it's more than possible that they could have right?)?

I checked to make sure this topic had not come up before I couldnt find anything, sorry if it is a re-run topic though.

JSMeloche
07-30-04, 10:12 AM
Does your 2.0 litres engine boosted to 200 hp deliver smooth power and unmatch reliability? probably not
And the 4 cylinder probably doesnt have 200 lb/ft of torque either. The Northstar engine has 300 hp AND 295 lb/ft. What gives you the punch and acceleration is the torque.

A 460 hp N* is a reachable goal but probably needs a supercharger or twin turbo. When you boost an engine like this you sacrifice long term reliability. Numerous people on this forum have 120k and more on there N* and can still floor them DAILY.

A boosted/tuned 100hp/1000cc 4 cylinder will probably need a rebuilt by this time or not perform has well as it used to be.

The N* was design to acheive great horsepower, great torque, have unmatch reliability and smoothness of operation.

ShadowLvr400
07-30-04, 11:15 AM
Actually, doing 460 from the Northstar is reachable under N/A, but you'd be giving up smoothness, and possibly reliability. Cams, head, intake, and exhaust would easily do 460 horses. The thing is, you'd likely have to cam out till peak horse was at 7k, and peak torque at 5k or more.
There's also limitations on power for other reasons. Insurance gets touchy when a car is declared to have 400 horses, etc. The average Cadillac driver doesn't want 460 horses, they want a smooth motor that will move their cars quietly, and maybe once in a while, with some life. The 2.0L tend to scream a bit, even with stock exhausts. The Northstar is quiet under a stock exhaust, and doesnt sound strained under almost any circumstances.
You also have to factor in that the Northstar has, until recently, been under a FWD car. With FWD, too much power means a lot of torque steer. I can vouch that with around 410 horses, the car liked to dance. (I had a 125 shot of nitrous) The motor didnt seem bothered by the nitrous much, and the car itself held fine under 400+ horses. It just danced though...
There's also the factor of the vehicles the motors get mated to. The northstar is carrying cars that weigh around 4000 lbs. The average 2.0L is seeing cars in the 2000 to MAYBE 3000 lbs range. So the torque that comes with engine size is something to take note of.

speedyman_2
07-30-04, 01:13 PM
Does your 2.0 litres engine boosted to 200 hp deliver smooth power and unmatch reliability? probably not
And the 4 cylinder probably doesnt have 200 lb/ft of torque either. The Northstar engine has 300 hp AND 295 lb/ft. What gives you the punch and acceleration is the torque.



Exactly!! This is what is so hard to pound into the heads of 4-banger lovers. Yes they may make 100HP per litre. But, they have no concept of torque. And no matter how many times I tell them they don't understand. And I also tell them the reliability part. An engine with less torque is going to have to turn more RPM's to make power. Resulting in a lot more stress on the engine. But, the 4 banger bunch doesn't want to hear such things. I don't understand em, probably never will.
:hmm:

majax
07-30-04, 04:08 PM
Thanks for all the input guys it means a lot, i'll run that past my brother :devil:. He tells me those 4 bangers of his probably last forever, but the thing is when he gets his used one ordered from japan its gona have about 30,000 miles on it because over there the dont let you use a engine must past 40,000 or so.

95Concours
07-30-04, 06:08 PM
True, there are many small displacement japanese engines that make huge gobs of horsepower.... But how many of them do that without a turbo charger? Not many (if any), if you were to lower the compression and bolt on a turbo(s) with around 15psi (like most turbo imports) to a 4.6 NS, Im willing to bet 500hp+ is an easy goal... Also, there are several 'american' engines that get high horsepower ratings with smaller engines, the dodge srt being one of them... I'm not saying the the japanese 'muscle cars' are no good, I personally love many of them, but the NorthStar is a well designed engine. It does what yout average cadillac onwer wants it to do, give generous realiable power while being smooth and quiet. My two cents.

Ranger
07-30-04, 09:32 PM
The N* was design to acheive great horsepower, great torque, have unmatch reliability and smoothness of operation.
And on top of all that, great gas milage for a 4000# plus luxury car.

majax
07-30-04, 09:41 PM
Is my brother right when he calls the Northstar a "truck engine." Also aparantly the motors he speaks of have very sufficient amounts of torque.

growe3
07-30-04, 10:23 PM
The Northstar can easily attain very high power ratings, As noted the purpose of this engine is solid daily power to move around a moderately heavy car, with all of the trimmings.

CHRFAB has built many to the tune of 800 to 1,000+ HP. While immersive, these are not what I would call reliable daily driver engines; but they make some bad ass hot rods.

0-60 in mid 6's, a top governed speed of 150 MPH; I have no problem with the Northstar’s power output. As for the limitation of 300 HP, that is about all a FWD car can safely handle. The new RWD design has increased the power from 325 to 400 HP and still a very street-able engine for daily driving.

-George

Randy_W
07-31-04, 12:32 PM
Is my brother right when he calls the Northstar a "truck engine." Also aparantly the motors he speaks of have very sufficient amounts of torque.


No, he isn't right, it's far from a truck motor! The other thing nobody has mentioned is that it's much easier to get higher specific output per cc on a small engine, due to smaller rotating mass. I had an engine in a model boat that was .6 c.i. that put out over 3 h.p.! Tell your brother to try that with his Nip engine! That would be the equivalent of a 1.2 liter engine putting out 600 h.p.! All that with no N20 or supercharging! ;)

mike98c
08-01-04, 01:04 AM
The "truck engine" puts out more power at better fuel economy than the BMW and Mercedes engines of comparable displacement, but of course we know what poor engineering the Germans have become known for LOL.

carguy16
08-01-04, 07:47 PM
Several points people have already stated, not going to say them.

But, have your brother drive that 2.0 ltr with a car full of people and the A/C running, I'd like to see how far he gets.

Yes, 4 cylinder engines are loud, rough, and jerky. The car I drive has a V6, the power is smooth, and it sounds nice too.

Let's say a Diesel engine has 500 HP and 1500 torque, would he call that weak, because it only puts out about 125 hp a cylinder, for 6 cylinders?

And for the person with the Acura that got 525 torque and 500 HP, while it may achieve that on a Dyno, I seriously doubt is has that kinda torque. If so, put a trailor hitch on the back and step on the gas, or put some weight in your car.

4 cylinders arent always as hyped up as they are. Another example, take a push lawn mower for example. It has 4.5 HP, but you think its weak. You take some plyers, and tweak the throttle cable so the engine on the mower runs faster, there fore allowing you to cut the grass a little faster, or not have the mower bog down quicker. Point is, your just making it work harder. If you just got a bigger push mower with 8 hp, you would have no problems at all. But, some people dont need to modify their V8's as they have plenty of power, its only the kids in the 4 cylinders that need modification.

Aurora40
08-02-04, 12:05 AM
The other thing nobody has mentioned is that it's much easier to get higher specific output per cc on a small engine, due to smaller rotating mass. I had an engine in a model boat that was .6 c.i. that put out over 3 h.p.! Tell your brother to try that with his Nip engine! That would be the equivalent of a 1.2 liter engine putting out 600 h.p.! All that with no N20 or supercharging! ;)

Heheh, excellent! That's very true!

I also don't understand why people get caught up in hp/liter. Is displacement a precious resource? Is there a limited supply? No there isn't. So what really matters is hp/amount of fuel. What kind of mileage does your brother's 200hp car get? Is it better mileage than a 350hp Corvette? Look at a WRX STi. It makes 300hp and not a lot of torque. What kind of highway mileage does it get compared to a 350hp Corvette? So he can say his car gets more hp/liter, but who the hell cares when he gets smoked at the strip and at the pump? I'd rather have more horsepower overall than just more horsepower/liter.

Much of the reason for poor mileage on high-specific-output cars is that they make crappy torque. So they need low gearing to get off the line decently. Since you can't have an arbitrarily large transmission, the upper gears are shorter too and mileage suffers. If a small engine making a lot of power can't be as efficient as a larger engine making more power, then how is that possibly considered "engineering" to go that route?

In the narrow world of things like F1 where displacement is rigidly fixed and cars are impossibly light and rarely have to start from a stop, high horsepower and crummy torque are acceptable. But in the real world it makes for a very poor overall car. There is much more to an engine and to engineering one than just the peak power or the peak power/displacement.

BeelzeBob
08-02-04, 04:24 PM
An engine is an air pump. The more air it pumps the more fuel can be burned and the more power can be made. You cannot make the engine make more power by simply putting more fuel into it without the air to burn so the concept of the "air pump" is very real.

For a 2 liter engine to make 200 HP it has to pump a lot of air.... The only way to make it pump more air is to rev it up higher. That is why the power band of the (rare) 100 Hp/liter engines is up around 8000 RPM or so. Such as the Honda S2000. They rev the engine very high to enable it to pump enough air to burn enough fuel to make that much power. Problem is that the cam timing and ports and valve events(overlap) required to rev to 8000 make the engine a very poor air pump at lower RPM's....so they do NOT make much torque down low. This is OK if you have a light car with a manual transmission. It doesn't work with a heavy luxury car with an automatic transmission and lots of accessories. You need torque down at low RPM to move the luxury car. That you get with displacement. Period.

Your "brother" is simply demonstrating his lack of understanding of engines and torque and horsepower with his comments. He is looking simply at lightweight cars with manual transmissions. Those cars get away with 2 liter engines fine. Heavier cars do not.

If he thinks that the 100 HP/liter engines have "sufficient" torque then he has never driven one....they do not have much if any appreciable torque down at lower RPM's where the engine is pleasant and quiet and pleasing to drive on the highway. The high output engines like you describe MUST be revved to very high RPM's to make any torque/HP. Drive a Honda S2000 and tell me I'm wrong. They do not have much torque below 6000 RPM.

Fundamentally, if the volumetric efficiency of the engines are similar, the ONLY ways to increase maximum torque is to increase compression (some improvement), increase displacement (huge gains) and/or add a blower. Changing the cam timing/events does not creat torque, it just moves the torque peak around.

EVERY automaker uses displacement to add torque to powertrains for heavier car/truck applications. There is nothing unusual about that.

Finally, your brother needs to understand that there is no "perfect" engine for ALL applications. That is why there are so many different types and sizes of engines out there. Comparing a 2 liter in a rice rocket to a luxury car or a truck is not a reasonable thing to do. They are two different types of engines designed for two different purposes. Neither is right or wrong, good or bad....they are just different.

There is an issue with larger displacement engines in regard to HP......simply physics. Larger displacement engines have larger cylinder bores and larger combustion chambers. Assuming that all engines have a centrally located spark plug the larger the bore the farther and farther the outer reaches of the chamber are from the plug as the bore increases. This makes the chamber more and more sensitive or susceptable to detonation....so....the larger the displacement the engine the lower the compression ratio must be. 1 liter motorcycle engines that rev to 15000 RPM with 60 mm bores can run 12.5:1 compression on regular fuel due to the tiny bores. 93 mm bore car engines designed for relistic operation at 6000 RPM can only run 10.5:1 compression with premium fuel due to the larger bore size and the increased distance from the plug to the end of the chamber. See....gasoline burns at the same rate regardless of octane or compression so the farther the flame front has to travel (larger bore) the more time the mixture has to detonate and cause destruction....so the compression ratio must be lowered. And torque/HP production is hurt as a result. You will never see large bore engines with high specific HP numbers because of this. Just a fact of life/physics. Nothing to do with truck engines or anything.

BeelzeBob
08-02-04, 04:28 PM
BTW....point out to your brother that some of the highest specific output engines on the planet are the highly tuned prostock drag race engines. Simple old pushrod "truck" style engines......LOL.

majax
08-02-04, 05:07 PM
:D :D Thanks for all the help guys!!!

Elvis
08-02-04, 05:29 PM
bbob does it again. I've always liked the air pump analogy. Great post.

As a satisfied Honda customer for the past 4.5 years, I'll be the first to tell you that comparing Honda HP and American V8 HP is just like comparing apples & oranges.

The statement about cam/timing changes is true also. This is why VTEC doesn't kick in until around 5400 RPM. You can buy a VTEC controller to override the computer, but the gains in smoothing out the power band are minimal. Usually people don't mess with a VTEC controller until after they've already done I/H/E, ignition, and in some cases a new flywheel.

I could've spent $10,000 modifying my Prelude, and I still wouldn't have been able to take an STS from a stop light. 1/4 mile maybe, but it would've been close. There's no replacement for displacement.

Another argument that doesn't get a lot of discussion is this: Theoretically, a 4.6L engine should burn 2.3 times more gas than a 2.0L engine. Doesn't work that way, does it?

Stoneage_Caddy
08-02-04, 09:17 PM
There is an issue with larger displacement engines in regard to HP......simply physics. Larger displacement engines have larger cylinder bores and larger combustion chambers. Assuming that all engines have a centrally located spark plug the larger the bore the farther and farther the outer reaches of the chamber are from the plug as the bore increases. This makes the chamber more and more sensitive or susceptable to detonation....so....the larger the displacement the engine the lower the compression ratio must be. 1 liter motorcycle engines that rev to 15000 RPM with 60 mm bores can run 12.5:1 compression on regular fuel due to the tiny bores. 93 mm bore car engines designed for relistic operation at 6000 RPM can only run 10.5:1 compression with premium fuel due to the larger bore size and the increased distance from the plug to the end of the chamber.

so maybe a 4.6 litre 16 cylander would be the ticket ?

Explains why F1 has around 2-3 litre displacment and 10 cylanders reving around 20,000 rpm

one more thing , is this why manufactuers have sometime gotten more power from a 2 plug per cyalnder head (mercedes benz)?

BeelzeBob
08-03-04, 09:54 AM
Good point about the fuel economy issue with larger displacement engines. The effective use of EGR, friction reduction and good calibration parameters..i.e...electronic controls.... mitigate the inherent pumping losses of a larger displacement engine running at part throttle. The use of the variable displacement engines (the V-8-6-4 of yesteryear and the upcoming "displacement on demand" systems) mitigates the pumping losses even further allowing even better fuel economy with a large displacement engine.

Adding cylinders....i.e...a 16 cylinder 4.6 liter engine.....adds friction so it isn't a given to making more power or torque. Generally speaking going to more cylinders allows smaller bores and shorter stroke allowing more compression and higher revs (less piston speed) but it is a very complex formula/puzzle involving mass, complexity, cost, size, etc.....

Don't be mislead by what F1 does. They are building engines to a very very specific set of rules and regulations. One change and the entire engine architecture could change for a totally different reason.

The multiple plug setups can help overcome the disadvantages of a larger cylinder bore and does tend to enable more compression without detonation constraints in a large cylinder bore, yes. One other reason for multiple plugs is to minimize HC emissions in a larger cylinder bore with multiple valves. With a symetrical combustion chamber with a centrally located plug the material that is "packed" into the ring lands as combustion starts and pressure rises is raw HC because the "burn" hasn't reached the perimeter of the combustion chamber. These raw HC will escape during the exhaust stroke when the pressure is low. The idea is to complete part of the combustion chamber burn before pressures rise so that inert, burned material is packed into the ring grooves during the later stages of combustion. By putting one plug near the cylinder wall this can occur. Even burning 25 % of the perimeter of the chamber will reduce HC emissions by 25% so the effect is very pronounced.

rash_powder
08-03-04, 09:31 PM
i don't think the guys in japan are doing it right. my triumph sprint st (motorcycle) has a 955 cc (less than a liter - though not much) is a 3 cylinder that puts down 118 horsepower. the sport-bike model, the daytona 955, uses the same engine with different cams and computer and puts down something like 145 hp. i think the rice-burners need to get some engine building/tuning help from the brits.

rash

davesdeville
08-03-04, 10:33 PM
If you stick a 300hp northstar in the little japanese car with the 200hp 2 liter, it will be considerably faster. I still fail to see why hp/displacement matters. And if you look at the cien XV12, that was rated at 750hp/7.5L, so it's not like it's impossible to get 100hp/L from a big engine.