I showed my Dad some articles of these Tuner cars getting 400+ hp and torque. He was amazed at the power they're getting out of these 4 bangers. My Dad has a Dodge Ram with a Hemi that has 350 hp and 375 torque. Last Sat. were were towing a 19ft boat bothe the truck and boat had full tanks of gas. We had 5 people in the truck plus coolers etc. Fully loaded. We came up to a very steep and long bridge doing about 55 mph. My dad said lets see what this Hemi will do. When we were at the top of the bridge we had sped up to 70 mph. He said now let me see one of those 4 bangers do that. I didn't know what to say. Could a 4 banger boasting that much hp and torque do that and if not why?
Ok back to the question. I guess I should've been a little more exact on the question. Could a 4 banger (Motor) not a car, pull the load? It seems like with the proper gearing, rearend and suspension it could. I didn't meen for this to turn into a war about rice cars and muscle cars. I myself prefer the 8 cyl. sound and is why I am doing a 4.5l swap. I'm sure the super charged 3800 is a screamer but you can't help loving the throaty sound of an 8.
Bonzo
[This message has been edited by bonzo (edited 07-31-2005).]
Yes the four cylinder equiped with the right gearing and frame could definatly do it. Maybe not exactly the same fasion but it should be able to do, but for how long i dont know.
Ok back to the question. I guess I should've been a little more exact on the question. Could a 4 banger (Motor) not a car, pull the load? It seems like with the proper gearing, rearend and suspension it could. I didn't meen for this to turn into a war about rice cars and muscle cars. I myself prefer the 8 cyl. sound and is why I am doing a 4.5l swap. I'm sure the super charged 3800 is a screamer but you can't help loving the throaty sound of an 8.
Bonzo
Sure, a four cylinder with given power output will pull just as well as an 8 (or 12) cylinder with the same output. Ultimately what matters is how much torque at the drive wheels, and there are as many different ways of getting there as there are different motors. Regarding hauling/pulling capabilities, the Unimog comes to mind: http://www.cs.brandeis.edu/~zippy/unimog-404.html
As the others said.. 400 is 400, doesn' tmatter how many cylinders.. Yeah, it'll probably be higher revving, you can accomodate for that..
True 400 is 400 but the engine with 4cyl has to work harder to produce the same result as a 8cyl engine. Which means more stress, wear and tear on the smaller engine and drivetrain.
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Originally posted by befarrer:
Not many people would rev a vehicle to 6000+RPM to accelerate from a stop.
I wonder just how long the clutch and trans would last if you had to do that day in day out?
[This message has been edited by Unrivaled (edited 07-31-2005).]
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06:46 PM
Aug 1st, 2005
Pyrthian Member
Posts: 29569 From: Detroit, MI Registered: Jul 2002
Here is a quote from an article on towing, you will notice that calculations are based on curve (kerb) weigh: "How do I know how much my car can tow?,
or to put it another way, how big a car do I need to tow that caravan? This one is quite easy to work out for yourself with a bit of paper and your car's handbook.
First off, jot down the car "kerbweight" from the handbook. Let's assume it's 1670Kg, a medium sized car. Divide that figure by 20. (we're making it easy, remember!) That gives us a figure of 83.5, call it 84. Next multiply that 84 by 17, ok a bit harder, but you can use a calculator if you have to.
That gives us 1428 back in Kg again, so 1428Kg is the recommended maximum weight of caravan for your car. Now you will see suggestions that "experienced" caravanners can tow up to higher maximum weights, but if you don't know how to work these figures out, then you are not sufficiently experienced to be trying this, are you?
To work out for a car to tow a particular weight of van, simply reverse the process. Divide the caravan weight by 17, then multiply that figure by 20 to give you the kerbweight you need to pull it comfortably"
Also none of these take into account tounge weight or suspension. The reason a truck can tow more than a car is that you can place the hitch weight right over the suspension using a fifth wheel rig and get heavier duty brakes. You also could get a trailer with electric brakes and this is required in some states by law base on the weight being towed. Here is another web site on towing with a car: http://www.caravanning-online.co.uk/caravan_safety/safe_towing.htm
You will notice that their suggestions are based on weigh also.
True 400 is 400 but the engine with 4cyl has to work harder to produce the same result as a 8cyl engine. Which means more stress, wear and tear on the smaller engine and drivetrain.
# of cylinders means nothing - VE and displacement do
you can have a 3liter 4cyl or a 3liter v8 - people get so hung up on the number of cylinders
To work out for a car to tow a particular weight of van, simply reverse the process. Divide the caravan weight by 17, then multiply that figure by 20 to give you the kerbweight you need to pull it comfortably"
funny - there are a lot of trucks rated to pull 3 times their weight
most of towing capacity is based on towing method - (distance of tong from rear axel, 5th wheel, etc) tongue weight and rear suspension strength, power, and braking ability.
On an engine with a 4" stroke, each revolution of the motor moves a piston 8 inches. At 4,000 RPM that piston is moving 4,000 x 8" x 60 minutes/hour = 1.92 million inches per hour, or 363 mph. Now, the speed isn't linear, the piston moves slowest at top and bottom and moves fastest at exactly half stroke, I don't remember how to calculate the instantaneous speed at half stroke, but for purposes of comparision we can probably ignore that. Now, take a 3" stroke motor, 4,000 x 6" x 60 minutes/hour = 1.44 million inches per hour, or 273 mph. That's a nearly 25% reduction in speed, so a shorter stroke motor can spin higher RPMs (all else being equal) before running into problems with velocity-induced oil film failure on the rings and ring flutter.
IMS, a 4" stroke means that each revolution of the motor moves the piston 4 inches, not 8.
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12:24 PM
Lambo nut Member
Posts: 4442 From: Centralia,Missouri. USA Registered: Sep 2003
Yeah, that would be 8" total movement per revolution.
Oh, and the speed at TDC and BTC is 0 mph. That would put the max piston speed at 2x your calculated speed per distance, but it's not linear acceleration. The acceleration graph will be a sine wave, and I'm not remembering off hand how much impact that will have, but it will make the max speed less than that 2x theoretical max for the linear acceleration model.
[This message has been edited by Formula88 (edited 08-01-2005).]
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01:30 PM
crzyone Member
Posts: 3571 From: Alberta, Canada Registered: Dec 2000
# of cylinders means nothing - VE and displacement do
you can have a 3liter 4cyl or a 3liter v8 - people get so hung up on the number of cylinders
The topic is referring to tuner cars with smaller displacement 4 cyls vs a 350 cubic inch 8cyl hemi so the number of cylinders do matter. I have yet to see a 350 cubic inch 4 cyl maybe there is a car with one out there but I'm just not aware of it.
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Originally posted by crzyone:
But a turbocharged straight 6 would wear out too fast, it has to work much harder than a V-8...
Crzyone I have not seen any mention of 6 cyls.anywhere in this thread.
yeeeeeah?.. But 400 lb/ft is 400 lb/ft.. Sigh.. Did you not read what we were arguing?
First you were arguing 400hp is 400hp, now you're changing it to 400 lb/ft is 400 lb/ft. True but it matters how, when and where in the powerband you make those numbers. And the hemi makes it sooner and flatter.
[This message has been edited by Unrivaled (edited 08-01-2005).]
If you take the original question on it's face value. Hp = Hp and Torque = Torque regardless of the package that it is in. If a tuner engine was placed into your dad's truck mated to a transmission that would allow the engine to stay in an RPM range that matched it's power band it would pull the same load. The problem is that the lesser cubic inch engine can't provide that power and torque reliably for as long as the greater cubic inch engine. The smaller engine is simply running closer to the edge of it's capability. Your dad's Hemi will deliver those Hp and Torque numbers all day long, day in and day out reliably, the smaller engine will deliver those numbers but over a much shorter life span.
------------------ RickN White 88GT 5spd White 85GT Auto
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12:32 AM
Formula88 Member
Posts: 53788 From: Raleigh NC Registered: Jan 2001
At power peak, with proper gearing, both style engines would be comparable. The big problem with the tuner engine will be getting started. You're going to need a seriously low 1st gear just to get rolling because it can't start in it's power band.
Once they get moving, that's not an issue. But it's a primary reason why large, low rpm engines are good for towing. They put out good torque even when they aren't in their power band.
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08:23 AM
Pyrthian Member
Posts: 29569 From: Detroit, MI Registered: Jul 2002
Originally posted by Unrivaled: We all know semis can haul, it is the 4 cyl tuner cars that's in question. BTW semis are diesels, do you know of any 4cyl tuner cars that are diesels?
and the question was could they do it - not for how many thousands of miles and how practical would it be.. the answer is "YES IT COULD DO THAT" - but would you really want it to? no its not what its designed to do.
and the question was could they do it - not for how many thousands of miles and how practical would it be.. the answer is "YES IT COULD DO THAT" - but would you really want it to? no its not what its designed to do.
Ok then name a tuner car that can do it straight from the factory with no modifications other than the addition of a hitch?
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09:39 AM
Pyrthian Member
Posts: 29569 From: Detroit, MI Registered: Jul 2002
Originally posted by Unrivaled: Ok then name a tuner car that can do it straight from the factory with no modifications other than the addition of a hitch?
then its not a tuner car - not a tuner car untill its modded - and stickers dont count - thats a ricer car. but anyways, we all know what's going on here. Brute Force vs Efficient Power. if its one hill, one time run, the rice buggy wins. if its everyday for a year, the lard wagon wins.
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09:53 AM
DelawareFiero Member
Posts: 1050 From: Tod vor Schmach!! Registered: Apr 2004
then its not a tuner car - not a tuner car untill its modded - and stickers dont count - thats a ricer car. but anyways, we all know what's going on here. Brute Force vs Efficient Power. if its one hill, one time run, the rice buggy wins. if its everyday for a year, the lard wagon wins.
I guess you're right about a tuner car is one that is modified. However, I don't concede a tuner car besting the hemi remember it takes more than hp to tow and I don't think a lightweigh FWD tuner car fits the bill.
[This message has been edited by Unrivaled (edited 08-02-2005).]
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10:01 AM
Pyrthian Member
Posts: 29569 From: Detroit, MI Registered: Jul 2002
Originally posted by Unrivaled: I guess you're right about a tuner car is one that is modified. However, I don't concede a tuner car besting the hemi remember it takes more than hp to tow and I don't think a lightweigh FWD tuner car fits the bill.
yup. and thats why EVERYONE who tows regularly ends up with a Deisel & RWD. low RPM torque & traction where ya need it - on the loaded wheels. only thing better is electric (like trains - the REAL tow vehicle). just picture a 2.0L rice burner - gotta be spinning 5000 RPM to get any power, then slide the clutch for 100 FT while they get rolling. there will be NO clutch left. then the load down. 4 poor little over stuffed pistons trying to pull a boat up a hill. the right tool for the right job. you never see 700 HP F1 motors at a tractor pull, and you never see 700 HP tractor motors in a F1 car. its how you want them 700 ponies put to the ground - high RPM or low RPM. everyone has a need, and we've got motors for all of them.
now, take tha "awesome" hemi, take to to the drag strip, and find a 4 banger of equal HP's and see who wins that race. well, lets make it a little fair - for weights sake - a 4 banger with 30% less power. and how about another fun challange - lets see who can go the furthest on $500 in gas. that over sized, overweight Hemi almost silly as a daily vehicle. not as useless as an H2, but close.
yes, there are actually people who have need for such vehicles, but the Mom's at Farmer Jacks, who cant even fit the things into a parking space or even worse - use reverse, make me like the ricers more than the Faux Truckers. "What Ya Haulin?" - my fat ass.....
Originally posted by Unrivaled: Ok then name a tuner car that can do it straight from the factory with no modifications other than the addition of a hitch?
can't say I understand what your question has to do with my statement - the fact that it doesn't come from the factory that way simply supports my statement
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Originally posted by DelawareFiero: Let it go bro. Youre dealing with people that actually go out and buy a 4 banger for the performance. Some peoples kids, sad.
ok who the hell do you think you are talking to? think I am some dumb little highschool kid? god I hate people who think that anything thats more modern than the old mentalities engrained into the skull is a "KID" oh they must be a KID because they sure don't "KNOW" the facts like me huh? did I go out and buy a 4cyl for to make it beat a v8? grow up
how about a turbine engine.. if it can lift your hemi powered pickup into the air.. do you think it can tow ? engines don't have to be big to make usable power - they don't have to rev slowly to be reliable -
when is the last time a pickup used its peak HP to cruise on the highway.. it uses a fraction of it power to cruise and the rest just to get up to speed.. how int he world could a high power 4cyl ever do that? oh my goodness nobody would ever think to have a few low towing gears to convert higher rpm hp into low rpm torque.. oh nooo - the horror
why do they use big v8's in trucks? because the ball scratchers get to feel like they have a big pecker, it sells, its cheap to make, all these things make it practical could they make 4cyl or turbine trucks that'd possibly tow even better? yes - but whats their motivation..
the only thing the number of cylinders does is affect the sound of the engine - no not size.. displacement affects size -
don't know why I even bother interjecting science into these discussions - people already have been convinced what they want to believe and what prejudices they wish to harbor (yes looking down at a car because is has fewer cylinder is a stupid prejudice)
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11:53 AM
PFF
System Bot
crzyone Member
Posts: 3571 From: Alberta, Canada Registered: Dec 2000
A 400hp turbo 4 will still kill a 350hp hemi in towing. The turbo 4 has the same powerband as the hemi, just bigger. Hell, an SRT-4 with a stage 3 upgrade puts down
Explain to me why the srt-4 has to rev to 5000rpm to get a load moving? It has just as much torque or more than most V-8s out there.
I'll say it again. The SRT-4 engine in a dodge ram putting down 400hp will out accelerate a 350hp hemi. There is no magic involved, the srt engine just has more power. How hard is to understand? Nobody will put a 4 banger in a big truck, its not practical, but it will pull just as well.
400hp>350hp
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12:02 PM
Pyrthian Member
Posts: 29569 From: Detroit, MI Registered: Jul 2002
Originally posted by crzyone: Explain to me why the srt-4 has to rev to 5000rpm to get a load moving? It has just as much torque or more than most V-8s out there.
that was me - I just dont know any better - never had a 4-banger turbo.
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12:12 PM
Oreif Member
Posts: 16460 From: Schaumburg, IL Registered: Jan 2000
A 400hp turbo 4 will still kill a 350hp hemi in towing. The turbo 4 has the same powerband as the hemi, just bigger. Hell, an SRT-4 with a stage 3 upgrade puts down
Actually in towing, No it won't. The dyno is an engine dyno (at the crank) so look at 1500 rpm. The 4-cyl has about 60hp and 180 torque. A hemi in a Ram has 160hp and 275 torque (at 1500rpm's) AT THE WHEELS on a chassis dyno*. When towing the ability to start to move the weight is a very important part. Towing a 19ft boat on a trailer, The 4-cyl turbo truck would bog and strain until the weight started to move or the engine created enough power to move the weight. It is the cubic inches of the V-8 that allows the higher low end torque to move the weight from a dead stop easier. Thus accelerate faster. If both were traveling down the road at say 45mph, the 400hp would have the advantage in acceleration as long as the RPM's were (based on the SRT-4 dyno) over 2800 rpm. Even still the hemi would have more horsepower and torque at that rpm. The hemi peaks at about 4000 then the torque starts to drop out. The 4-cyl would have the advantage of more power and higher rpm range, but from a dead stop, or even a low speed roll, the hemi would take off faster as the higher HP/torque would move the weight faster. Once the weight was moving, the higher HP/torque 4-cyl turbo would accerate faster and possibly pass the hemi. In the situation listed in the first post of this thread, The hemi would have the advantage of being able to move the weight better at low rpm than if the truck had a 4-cyl turbo. As you stated, HP is work, So with a 3500lbs trailer 160hp will start to move the weight faster than 60hp. Peak horsepower and torque has nothing to do with the ability to tow. If the 2 trucks were the same weight/gearing, The hemi truck would launch off the line first and most likely have a better 60' time, But the turbo4 would they catch-up and pass the hemi truck by the 1000' mark (or sooner). Low end torque gives the vehicle the advantage at the start of the race, high horsepower gives the advantage towards the end of the race.
* = Dyno results are on the Ram forum with a hemi engine equipped with Dynatech headers.
[This message has been edited by Oreif (edited 08-02-2005).]
that assumes the same gearing or the same stall toque converter in an auto tranny - if it was an auto (and they pretty much all are now) then a slightly higher stall converter in the 4cyl will make up the difference of what it put to the wheels att he same wheel rpm (different ngine rpm)
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02:11 PM
crzyone Member
Posts: 3571 From: Alberta, Canada Registered: Dec 2000
I mentioned having a higher stall converter a long time ago in this thread to take away any disadvantage off the line.
Since the hemi had a rolling start, the 4 would be faster. As soon as the truck dropped a gear under hard acceleration both engines would be in their powerband, the 4 having more hp would start to pull away fairly soon.
This argument is pretty silly. This would never happen but yes a 400hp 4cyl is a powerful engine any way you cut it.
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02:27 PM
crzyone Member
Posts: 3571 From: Alberta, Canada Registered: Dec 2000
Theoretically: If there was a way to keep each motor at their peak horsepower via gearing, with no power loss in the transmission. The higher powered car would win. Seeing how this is not the case you have to look at the torque curve. At say 1500 rpm A hemi would start accelerating at lets say, 2ft per s^2, the 4 cylinder at 1ft per s^2. From the torque curve, the Hemi's acceleration curve would be more linear. The 4 cylinder would need to wind up then start accelerating at 2.5 ft per s^2 with its more exponential shaped torque curve. In the long run though, while the four cylinder would have accelerated the load at a faster peak acceleration, the hemi would have the higher average acceleration ultimately being the winner. If you could get the same torque curve out of a 4 cylinder as you could a hemi, then perhaps it could do it.
Reliability side of this arguement has already been established. A four cylinder designed for 150 hp pumping out 400 hp will not last as long as the motor designed for 400hp.
Those straight six cylinder motors that trucks put out around 600 hp and 2050 FT LBS of torque. I've seen a video of a hayabusa putting out 700hp and only 300ftlbs of torque. Do you think that hayabusa motor is going to accelerate that load FASTER than that truck, let alone get it moving?
Why is it you think that companies would concentrate so much on torque of the vehicle rather than HP if HP is all that matters? That after all cryzone, is a 'work accomplished' correct? It takes torque to accelerate an object..
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03:33 PM
Capt Fiero Member
Posts: 7657 From: British Columbia, Canada Registered: Feb 2000
It is FACT larger displacement with all things being equal, makes more power.
You can mod a small displacement motor to make big power
But bigger motors make bigger power.
I can't see why this has to be argued.
That 4 popper has a turbo then lets put a turbo on that V8
Oh but that 4 popper has a DOHC setup, OK lets get a DOHC Turbo V8 uhm, see where I am going. Wasn't it Callaway that made a Turbo Vette was a small block chevy that mad 800hp on pump gas and could be used as a daily driver.
More displacement means more power assuming all things are equal. Anyone that wants to argue that point is arguing just to argue.
------------------ 85GT 5spd MSD Everything,4.9 With Nitrous. www.captfiero.com
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03:43 PM
crzyone Member
Posts: 3571 From: Alberta, Canada Registered: Dec 2000
.......i think ill sell my car now.......
