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cs
05-15-2009, 08:53 AM
A recent started me thinking of this again. I'm of the opinion that all things being equal that there is no replacement of displacement. I'm not saying now that you can't get great numbers out of smaller engines.

What I will say is that while you can turbo charge and supercharge, use fancy ignition, and fancy injection, that you can get those small motors to perform great, you don't have to do that much to a big motor to get there. Imagine if you will what you would get if you invested that much into a bigger motor.



A staple motto of the American muscle car (http://everything2.com/title/muscle%2520car) crowd. It means that engine size (displacement) is the ultimate horsepower (http://everything2.com/title/horsepower) producing factor of a car, and that other horsepower-increasing devices, such as turbocharger (http://everything2.com/title/turbocharger)s can never fully substitute.
This motto has sound basis. An engine with a small displacement (http://everything2.com/title/displacement) can be modified by car manufacturers to have a relatively large horsepower (http://everything2.com/title/horsepower) in several ways, the most important being cam (http://everything2.com/title/cam) modifications.
Cam modifications shift the torque curve (http://everything2.com/title/torque%2520curve) in a certain direction; in this case, toward the high-end range. Since power (http://everything2.com/title/power) is proportional to torque (http://everything2.com/title/torque) times speed (http://everything2.com/title/speed), torque (http://everything2.com/title/torque) produced at a higher RPM (http://everything2.com/title/RPM) level will yield more power. This type of cam modification is used religiously on Japanese cars, allowing cars like the Toyota Celica (http://everything2.com/title/Toyota%2520Celica) to get 150+ horsepower out of a Geo Metro (http://everything2.com/title/Geo%2520Metro) sized engine. However, there is a catch. This type of cam modification means the engine will only start making sufficient torque and horsepower at very high RPM's. For example, the Celica makes peak torque at around 6,000 RPM and peak power at around 7,500 RPM. Torque is the turning force that allows cars to accelerate. The more torque, the faster the car accelerates. To have to rev up to 6,000 RPM (which is the engine redline (http://everything2.com/title/redline) of most cars!) just to get sufficient torque for a fast launch would take a long time, and the massive amount of high-pitched noise that is produced at such a high RPM level hinders any pleasurable experience one may have from driving the car.
An engine with a large displacement, however, has enough horsepower being produced by merit of its size that no radical cam modifications are needed. Therefore, there is much more low-end torque (http://everything2.com/title/low-end%2520torque), meaning that the torque is readily available at commonly-reached RPM levels. The Chevrolet Camaro (http://everything2.com/title/Camaro)s of old, with their 300+ cid (http://everything2.com/title/cid) displacement, had a torque peak around 2500 RPM!



Source (http://everything2.com/title/There%2527s%2520no%2520replacement%2520for%2520dis placement)



Chad

The Bigfella
05-15-2009, 08:57 AM
Actually Chad, the lazy way to get a set of performance figures is to build a big engine (displacement). From there, the same output can be had in any number of more efficient ways.

By all means, go the displacement route - but be prepared to pay the price at the pump.

cs
05-15-2009, 09:02 AM
I'm not saying it is the most fuel efficient way to get there.

What you fail to see is that if you spend the kind of time and money on a larger motor rather than a smaller motor you will have a motor that produces way more. To get a smaller motor to perform to bigger motors standards you have to do all kinds of crazy stuff.

Bottom line is with all things being equal, there is no replacement for displacement.

Chad

The Bigfella
05-15-2009, 09:03 AM
Bull****

Tylerdurden
05-15-2009, 09:07 AM
This may be a replacement for displacement. I think full torque at 1 rpm is just the ticket. Imagine the boat possibility's.

http://engineeringtv.com/blogs/etv/archive/2008/06/03/cyclone-external-combustion-engine.aspx

Popeye
05-15-2009, 09:08 AM
getting lots of low end torque in small displacement engines is easy, if you have a longer stroke you get more torque

the first vw gti i owned pulled like a train

John Smith
05-15-2009, 09:08 AM
Following the gas lines in the 70's, Buick could not sell the V8 Century, so it offered a 6 cylinder with turbo charging. This it could sell.

I believe it was Consumers Union that tested the V8 model against the V6 model with turbo charging.

They found the V8 did everything better on less gas. Perception was everything, and the public would not have 8 cylinders at that point in time.

We had in our family three '65 full size Dodge cars. One had the 225 six, one the 318 V8, and one the 383 V8. The 318 got the best gas mileage, and performed quite nicely. It was obviously the most efficient power for that size car.

Popeye
05-15-2009, 09:16 AM
there is no joy in having all that extra weight over and under the front wheels , and then being forced to deal with a solid rear axle and all the ensuing crap in between slowing you down and robbing performance

real dinosaurs man

LeeG
05-15-2009, 09:18 AM
aphorisms don't exactly make for good design. Speaking from relative ignorance here but does a high revving low displacement engine provide better acceleration at high rpms for a given rate of fuel consumption than a big engine with broader power band?

The Bigfella
05-15-2009, 09:23 AM
aphorisms don't exactly make for good design. Speaking from relative ignorance here but does a high revving low displacement engine provide better acceleration at high rpms for a given rate of fuel consumption than a big engine with broader power band?

Check out what's available for sale these days. Check out the performance figures too. Yes, there are some fast large displacement engines (in specialised high $ vehicles) - but the amount of $ in those engines is way out of proportion. The trend in performance has been lower displacement, better managed, bolt on horsepower.

cs
05-15-2009, 09:23 AM
Missing the point Popeye, not saying older muscle cars are better, although they are fun.

Larger displacement gives more power at lower RPM's. Smaller engines have to live in the higher RPM range to produce the same amount of horsepower.

The way I see it bigger motor = more power (all things being equal).

Ian I expected better of you.

Chad

The Bigfella
05-15-2009, 09:25 AM
Missing the point Popeye, not saying older muscle cars are better, although they are fun.

Larger displacement gives more power at lower RPM's. Smaller engines have to live in the higher RPM range to produce the same amount of horsepower.

The way I see it bigger motor = more power (all things being equal).

Ian I expected better of you.

Chad

Yeah Chad, I guess you'll never see a lawnmower engine powering a container ship. Then again, you won't see a container ship engine in a Taurus.... so, whats your point?

cs
05-15-2009, 09:28 AM
Somewhere the other day somebody said what I said and somebody else said BS. So I started a discussion on it.

Chad

Popeye
05-15-2009, 09:30 AM
i hear you chad , i like muscle cars too , but they are only good at going in a straight line

for equivalent hp/weight the smaller car runs circles around the bigger car every time

The Bigfella
05-15-2009, 09:30 AM
and its a BS discussion without boundaries. I still want to see you pushing a lawnmower with a Dodge Viper engine on it.

cs
05-15-2009, 09:43 AM
Straight line is fun and driving circles is fun also. Each one has its purpose. I'm still not convinced that you can achieve greater power efficiency out a smaller displacement motor.

I like all kinds and I'm not married to bigger motors. Right now I'm more concerned about eco friendly rather than large fun cars. But I still love the pure power and adrenaline rush I used to get out of that old TA with the 455 ci engine.

Chad

LeeG
05-15-2009, 09:50 AM
Chad, it's neat all the ways power is expressed in an engine. I like the idea of small turbo diesels that have similar power bands as big old relatively low output V8 iron. Gobs of torque at 1500rpm with sufficient horsepower to accelerate up to freeway speed.

The Bigfella
05-15-2009, 09:54 AM
Chad, it's neat all the ways power is expressed in an engine. I like the idea of small turbo diesels that have similar power bands as big old relatively low output V8 iron. Gobs of torque at 1500rpm with sufficient horsepower to accelerate up to freeway speed.

and because they are lighter, they can go in lighter overall packages, so they perform even better, without 65% of the weight hung out in front of the car too.

Popeye
05-15-2009, 09:55 AM
problem with the big american iron v8 is it won't rev-up with the same silky feel you get in the modern 4 cyl jobbies

like leeg pointed out , the usable power band is there at cruise and hwy speeds , much better throttle response and of course lower fuel consumption for the same or better performance found in those old cudas and such

muscle car is ok for rolling around in downtown and sunday picnics
;)

cs
05-15-2009, 09:56 AM
Your right, it is kinda cool. Each engine, each size, has its own place.

That old TA I used to drive was fun, fast, strong and dangerous. Off the line it was a beast, if you knew how to tame it. In another vein though the RX-7 I used to own was just as fun, but in a different way. It didn't have same kick you in the pants power, but it was, for lack of a better word, peppy. It always had power where you needed it, no questions asked. The TA always had power, but you paid for it at the pumps. Just a note, I don't believe that the RX-7 could run with the TransAm I had, that is unless you threw in a couple of curves.

But you know probably my favorite was the couple of MGB's that I used to own. And we all know that MG had neither displacement nor power.

Chad

huisjen
05-15-2009, 10:00 AM
My ship had a 40' draft, and a 40 thousand ton displacement, but it could still only do 21 knots at flank.

Dan

Keith Wilson
05-15-2009, 10:00 AM
Displacement is the easy low-tech way to get power. You always pay for it in weight and size, and usually in fuel consumption. Weight is of course the mortal enemy of performance.

Another way to look at it is that RPMs are essentially free, and that the more you can get the better. That's not strictly true, of course, but it has some truth in it.

LeeG
05-15-2009, 10:01 AM
On a visceral level it's like riding a bicycle up a hill at 70rpm with 175mm cranks at a moderate aerobic output compared to pedaling at 90rpm on the flats with 172.5 cranks at the same output. They're both efficient but one can accelerate an extra 5mph faster starting at 90rpm than 70rpm.

LeeG
05-15-2009, 10:03 AM
My ship had a 40' draft, and a 40 thousand ton displacement, but it could still only do 21 knots at flank.

Dan

but how many games of football could you play on it at the same time?

Popeye
05-15-2009, 10:06 AM
a good way to think about displacement and power is to see the engine as a simple 'air pump' , the less cumbersome the better

and who ever can move the most air thru it , smoothly , wins

cs
05-15-2009, 10:12 AM
Keith I hear what you are saying, but I'm not 100% convinced. When you add displacement you do add weight, but how proportional is the weight to displacement?

Talking about RPM's and being better, lets think about this. I'll go back to my TransAm with the 455 cubic inch engine and the RX-7 with the 1.3 Litre (79 cubic inches). Now the RX-7 is one of those that comes pretty close to unlimited RPM's and the big 455 was not as a high of spinning engine.

Now this comes from experience, owning both cars and driving the hell out of them. The TA was faster on the top end, faster 50 to 100, faster in the quarter mile and was great at doing donuts. It had power at every tick of the tach (within its range) and not just power, but pin you to the seat power.

The RX-7 still had power and plenty of it, but not when you compare it to the output of the TA. Also keep in mind that the TA weighed considerably more than the RX-7.

Chad

Saltiguy
05-15-2009, 10:14 AM
I had an AC sports car with an aluminum Buick V8 in it. My memory is vague, but as I recall the engine had a ratio of one pound per cubic inch, per horsepower.
Engine block - sans flywheel and manifolds - approx 200 lbs
Cubic inches - 215 (?)
horsepower, with a bit of tweaking - 225 (?)
Can't remember the details, but in a 1500# aluminum bodied car, hooked up to a 4-speed, I had a screamer!

Keith Wilson
05-15-2009, 10:16 AM
The trouble with comparing piston engines to Wankel engines is that displacement doesn't mean the same thing. Is each rotor one cylinder or three?

If you want really high-revving engines, look at racing two-strokes, or even ordinary mid-size motorcycle engines. Power per cc, or power-to-weight is WAY beyond even the RX engine.

cs
05-15-2009, 10:19 AM
You're right on that. The 1976 KH-500 I used to own was rated at about 50 hp if memory serves. That is 33 year old technology that gives you 1.67 hp per cubic inch.

Chad

LeeG
05-15-2009, 10:26 AM
what gets me is that BMW has a single cylinder 650cc that gets 53hp.

Popeye
05-15-2009, 10:34 AM
T/A vs rx7 chad .. ? good grief man

the wrx sti will eat it

Keith Wilson
05-15-2009, 10:37 AM
I think a modern 600cc 4-cylinder sportbike can easily make 80HP right off the showroom floor at about 14,000 RPM, redline around 15,000. Race-prepped versions get over 100 HP. That's something like 2.2 HP/cu in for the street version. I don't know how much a Honda CBR600 engine weighs, but it's not much.

cs
05-15-2009, 10:40 AM
T/A vs rx7 chad .. ? good grief man

the wrx sti will eat it

I think that is a valid comparison for this discussion. Big cubic inches, low tech and small cubic inches higher tech.

In terms of pure power the 455 ate up the smaller Wankel (as well as volumes of gas).

Chad

Dan McCosh
05-15-2009, 10:41 AM
I was having dinner the other night with a guy who developed turbochargers.

"We are the replacement for displacement." He says.

"But it's a lot cheaper to make a bigger hole in a block of steel," I said.

Popeye
05-15-2009, 10:46 AM
"But it's a lot cheaper to make a bigger hole in a block of steel," I said.

i used to think engines were cast iron :confused:

Cuyahoga Chuck
05-15-2009, 10:49 AM
Back before gran prix roadracing motorcycles went the four stroke route the factory 2-stroke motors were making about 180 HP from 500 ccs. That's 180 HP from 30 cubic inches unsupercharged. Part of that was due to developements in electro-mechanical devices like fuel injection and the variable timing exhaust port. The electronically controlled exhaust port made the torque curve very fat so the bikes were much easier to ride fast.

LeeG
05-15-2009, 10:52 AM
speaking of complex replacement for displacement


http://www.mce-5.com/

Dan McCosh
05-15-2009, 10:54 AM
i used to think engines were cast iron :confused:

Also aluminum. Picky picky.

ChaseKenyon
05-15-2009, 12:04 PM
Wow you guys are poking into my turf big time here!

I am an engineer and have worked with the auto industry, and have been an automotive historian since I was 13.

This issue will deal with some basics and just some easily researched Studebaker facts.

Ok lets start with the 1930's. Miller engines here in the states won Indy with supercharged straight eights. It was the end of Studebakers winning stretch with straight eight Presidents taken off the production line and rebodied for racing. (I believe they won outright twice and dominated the top five at least two other times). The main reason they were able to do this was their leading technology in using 9 main bearings of the modern replaceable shell type which gave them a major higher RPM advantage. This allowed them to set some 33 international speed and distance records in November (1927or8 IIRC) at the board track with sleet falling in Atlantic City NJ. Many of those records stood until the late 50s or even into the 60s. Records with USAC with wired and sealed, no repairs allowed, on site over seeing the trials.

At the same time in Europe Bugatti was crucifying the competition in racing with high RPM small displacement supercharged straight 8s with like the Miller four valves per cylinder.

Ok now lets get a bit more modern. 1954 Indy Race. Studebaker took a production (true to their history) 289 V8 from the regular production line and set it up for A. Granitelli for Indy. They destroked it to 262 CuIn and added four valves per cylinder heads with polished Weslake Dual overhead gear driven cams style cross flow heads and heavily modified Hillborn fuel injection. Result was close to 400 bhp at 7300 Rpm (IIRC). Both engines and cars were extremely competitive and were in the top 5 in trials. Some bad weldments to add an extension shaft to the front of the crankshaft for the removable starter failed and keep them out of the race. the tooling and molds for the heads and all still exist in the hands of a STudie collector.

Now we can go forward to the early sixties. Many pundits refer to the GTO as the original "Muscle car" Not quite true. It was the one with the most advertising and hype, including songs that gave it an instant cult status. A 1964 GTO was having a good day at the drags if it could get into the mid 14s. This is not the 1960s Street catagory which allowed a lot of leeway, but the modern PURE STREET STOCK class. There were much faster cars including the 1957 rambler ambassador with it's rambler 327 V8 and the Studie Golden Hawk Supercharged 289 both of which could stay with and usually beat a 1957 fuel injected Corvette 283. It is once again RPM. The gear drive cams, repeat the gear drive cam engines much higher RPM capability tells out.

Fast forward to this new century.

Quick aside here then back to the main theme.

In 2003 several collectors took their Avantis back to Bonneville. (in 1962 at bonneville the Avanti had set records in class C (it's class) and class B and even broke the record in unlimited class A for production vehicles at 168 mph. In 2003 the Avanti crew took the class C stock production record back at 203 MPH. Within two more years they had raised the stock class C record to 213 MPH.


Ok now back to the present. Every year at the "National Pure Stock Muscle Car Finals" The same thing happens. Not just 64 GTOs, but 428 Judges, 440 sixpack Challengers, Hemi Roadrunners and more fall prey to the 62, 63 and 64 Studebaker Larks. Daytona R2 (supercharged 289) and 63 Lark R3s (SuperCharged and bored to 302 cu in with more radical cam).

Why? Contrary to false bravado in the Muscle car ranks almost all of the big block 400 cu in plus street stock muscle cars have trouble breaking into the 13s. (Once again PURE street stock.)Let alone the mid 13s which the R3 Daytona can do all day all year. Now you take the R3 and we are talking 13.1 seconds at 113 MPH in the 1/4 mile. THat is a 1964 street pure stock Studebaker Lark.

That matches most cars in 2008 from the factory hot rod divisons of BMW "M", Mercedes "AMG" Maserati "Sport", Audi RS, Jaguar ""R" (I am a lifetime Jag nut and past owner), and many more.

Next issue will discus the factory sport version of an tiny 4 door economy car That was kept out of SCCA racing for 11 years because naturally aspirated or with the turbo , either, it put out more BHP per liter than the top of the line current in 1991, Ferraris Porches, and many other top sports and the like cars.

As I am house bound most of the time from my back disability, if this is of interest let me know and I can post a regular automotive thingy with the references listed. We are a Wooden Boat lover's fraternity, but that does not mean especially her in the bilge that we can not also indulge in other common interests.

I can always research my library and report on any other automotive threads and questions from Albany cars to the history of Zil cars.


Chase:D

Captain Blight
05-15-2009, 12:08 PM
Chad,




What about turbines? I have no idea what the actual swept volume of that good Pratt PT-6 is; but I do know they'll put out upwards of twelve hundred horsepower briefly, and seven or eight hundred continupusly.

So displacement in and of itself is not a great indicator of horsepower potential. Displacement allows you to burn more fuel and extract more energy from the burning thereof; but so does packing more air into the cylinders via supercharging, by whatever means; or nitrous oxide injection. BMW's Motorsports division consistently produces engines that make well over 100 bhp/liter on pump gas and naturally aspirated, and these mills are reliable enough to last a quarter-million miles. The boys on the Bimmerforums are also taking these M3/M5 engines and installing new rings, putting hairdryers on them, and making close to double those figures. 600 BHP, or thereabouts, out of a 3.3/3.5 liter motor.

I really don't know how a 455 Olds block would respond to the same treatment. I bet when all is said and done, having used the smaller motor will have cost less to produce the same power.

Dan McCosh
05-15-2009, 12:23 PM
A 500 cid Hemi block makes an estimated 8,000 bhp or so in a top fuel dragster. Which is what happens when you pump a little air and fuel into a large displacement engine. Everybody else is just getting started to tune up.

cs
05-15-2009, 12:40 PM
Dan where did you get those estimates? They seem high, but I can believe it. That is what I've thought for most of my life, that if you put "bolt on HP" to a big block that you will get fantastic results.

Chad

Popeye
05-15-2009, 12:49 PM
if you put "bolt on HP" to a big block that you will get fantastic results.

those engines run for .. 5 ~ 6 (?) races and then are completely stripped down ..


anyone know ?

cs
05-15-2009, 12:57 PM
An F1 engine is only used once, if I understand it correctly.

Its smaller and spins faster (20,000 rpm).

Chad

PatCox
05-15-2009, 01:40 PM
Yeah, isn't that the rub with small powerful engines, and turbo, they have to spin much faster, and in the end, engine life depends on the number of times the engine spins around, not strictly miles or hours, all else being equal.

Captain Blight
05-15-2009, 01:52 PM
and turbo, they have to spin much faster, and in the end, engine life depends on the number of times the engine spins around, not strictly miles or hours, all else being equal.Well, sort of. True about the lifetime being measured in total revs (kind of) but I've worked on boats that have turbodiesels installed that redline at around 850-900 RPM. All a turbocharger does is use the exhaust stream to turn a wheel that helps pack more air into the intake side. More air means more fuel can be burned.

Another way of looking at it is to think of each atmosphere of pressure in the intake charge as doubling the volume of the engine: if you can run a 2-liter engine at 1 atmosphere of boost, then you can burn a 4-liter engine's worth of fuel. Bump the pressure up to 2 atmospheres, and you have a 6-liter engine, can burn 6 times the fuel and get 6 times the power-- all in a package that only weighs what a turbocharged two-liter does.

ChaseKenyon
05-15-2009, 01:57 PM
Yeah, isn't that the rub with small powerful engines, and turbo, they have to spin much faster, and in the end, engine life depends on the number of times the engine spins around, not strictly miles or hours, all else being equal.Yes if and only if both have similar internal designs for moving parts and bearing and oil pressure and , and , and......

Back in the days of sports Car Illustrated and Sports Car Graffic, (car and Driver and Road and Track now), Road test articles posted the feet per mile of piston travel as a semi clue to engine longevity. Porche's top engines had roller bearings like a Mercury Outboard, other cars also soon had superior designs for longevity in a high RPM engine. My 1991 Isuzu had a 1.5 liter engine with 4 vale cross floww heads and filled valves with individual coils rated at 130BHP but putting out 137 Bhp. It had nothing, no torque, no power below 4000 RPM. However, at 4400 It woke up like a bear with his Hibernation interupted. It was rated at top for 7800 RPM. After I built a jig to custom degree the cam when I replaced the timing belt at 178,000 miles it was up to 145 BHP. It was still running like a top and not burning a drop of oil at 256,000 miles when it was destroyed by a drunk hitting it from behind in a pickup that only had a handbrake working as he had the master cylinder out of the truck.

So small displacement high rpm longevity can be a matter of design and parts and most importantly the tollerances demanded as quality in production.

:D

Canoeyawl
05-15-2009, 04:13 PM
Today, the NHRA record for AA Stock is held by a '67 Ford Fairlane w/ 427 cu.in. pushrod V-8 -The old American V-8's are still contenders when we are going for elapsed time.

*note the date...
AA/S 9.68 138.79 03/07/09 Robert Pond - Riverside, CA
'67 Ford

Dan McCosh
05-15-2009, 04:22 PM
Dan where did you get those estimates? They seem high, but I can believe it. That is what I've thought for most of my life, that if you put "bolt on HP" to a big block that you will get fantastic results.

Chad

It's just a guess--the 8,000 hp. is an estimate based on the acceleration times recorded. The top fuel engines make so much horsepower and have such a short life span (about 10 seconds or so), that they can't be put on a dyno.

The limits of power are set by the effective pressure of the fuel burning on a piston. All other things being equal, it is the surface area of the piston (pistons) that counts, which quickly translates into displacement, depending on the expansion ratio. Anything you can do to a smaller engine can be done to a larger one. The small, high-output engines generally are limited by some rule, either a racing class or other regulation.

The progress of the GM small block over the years is interesting. In its early years, you could get about 500 bhp out of a racing version. Today, the same architecture is more in a production Corvette, with pushrods and a 2V head. That may be the highest output for a rather basic, large-displacement engine today.

I sort of remember that the BRM H16 F1 engine set a record for specific output (hp/liter), but don't know how it compares today. That engine had 16 cylinders, mechanical fuel injection, and one version managed four valves per cylinder---in a 3.0Liter engine.

PatCox
05-15-2009, 04:38 PM
I know Honda made a four cylinder 350 cc engine, and I am fairly sure that they made a 6 cylinder as well, at 350 cc.

ChaseKenyon
05-15-2009, 04:38 PM
According to GMC one of the main reasons to stay with the pushrod smallblock with the Vette is the narrowness and the small size and the extra top end weight of an overhead cam multivalve V8. THe Audi RS 4 revs to 8300 RPM With 414 HP as from the factory out of 254 cu in naturally aspirated. In bolt on upgrade to RS6 plus with a chip it is good for 475 to 550BHP depending on exhaust and other go fast components.

The current RS6 Avant is another story. It puts out 576 BHP from it's 304 cu in V10..... From the faqctory. It is not the Lambo Gallarda engine but a similar specific to the S series cars V10. Both V10s were designed by Audi. The S car V10 is currently available here in the S sedan.

All the above is available on wiki, and you tube road tests, not to mention all three of the audi forums I belong to.

Dan McCosh
05-15-2009, 04:59 PM
I know Honda made a four cylinder 350 cc engine, and I am fairly sure that they made a 6 cylinder as well, at 350 cc.

BSA made a 441 cc single-cylinder.

John B
05-15-2009, 05:43 PM
According to GMC one of the main reasons to stay with the pushrod smallblock with the Vette is the narrowness and the small size and the extra top end weight of an overhead cam multivalve V8. THe Audi RS 4 revs to 8300 RPM With 414 HP as from the factory out of 254 cu in naturally aspirated. In bolt on upgrade to RS6 plus with a chip it is good for 475 to 550BHP depending on exhaust and other go fast components.

The current RS6 Avant is another story. It puts out 576 BHP from it's 304 cu in V10..... From the faqctory. It is not the Lambo Gallarda engine but a similar specific to the S series cars V10. Both V10s were designed by Audi. The S car V10 is currently available here in the S sedan.

All the above is available on wiki, and you tube road tests, not to mention all three of the audi forums I belong to.


But Chase , those cars are selling for roughly triple and quadruple the cost of the pushrod cars.
Here , I can buy 400 plus odd hp GM for say 70k nz new.
The audis are 250 k NZ in some variants. I'd love one but its in my dreams .. plus , when I think about it ,I don't actually want to drive around in a car the price of an apartment.

John Meachen
05-15-2009, 06:23 PM
An F1 engine is only used once, if I understand it correctly.

Its smaller and spins faster (20,000 rpm).

Chad

No longer true.They are limited to 18,000 rpm and no more than eight engines are allowed in a season.The top fuel engines producing 8,000 hp do so for very brief periods;after each run they have the heads removed and the crankshaft and pistons removed for inspection.Four rebuilds per mile is not really something to aspire to.Back in the days of 1.5 litre turbocharged Formula one engines,the qualifying engines would produce 1,200 hp from one and a half litres and would last for at least four qualifying laps plus out and in laps.

John B
05-15-2009, 06:24 PM
No longer true.They are limited to 18,000 rpm and no more than eight engines are allowed in a season.The top fuel engines producing 8,000 hp do so for very brief periods;after each run they have the heads removed and the crankshaft and pistons removed for inspection.Four rebuilds per mile is not really something to aspire to.Back in the days of 1.5 litre turbocharged Formula one engines,the qualifying engines would produce 1,200 hp from one and a half litres and would last for at least four qualifying laps plus out and in laps.

F1 may longer be true full stop eh John.

Cuyahoga Chuck
05-15-2009, 06:27 PM
OK guys,these are the facts. The highest "specific output" of any piston engine ever produced was built by Suzuki for their 50cc roadracer c. 1969.
It had 3 liquid cooled 2-stroke cylinders that produced 19 HP between 18,500- 19,000 RPM, The narrow powerband made it a bitch to ride even with the integral 12 speed gearbox. It was never raced because the FIM changed the rules to one cylinder and a six speed transmission.

Dan McCosh
05-15-2009, 11:11 PM
No longer true.They are limited to 18,000 rpm and no more than eight engines are allowed in a season.The top fuel engines producing 8,000 hp do so for very brief periods;after each run they have the heads removed and the crankshaft and pistons removed for inspection.Four rebuilds per mile is not really something to aspire to.Back in the days of 1.5 litre turbocharged Formula one engines,the qualifying engines would produce 1,200 hp from one and a half litres and would last for at least four qualifying laps plus out and in laps.


Detuned to about a quarter of their max output, a supercharged hemi powered most of the Bonneville speed run cars as well, which requires about a 10-minute run. The last hemi, as I recall, hit some 430 mph though the traps on a one-way pass.

Bob (oh, THAT Bob)
05-16-2009, 04:52 AM
An engine twice as big, turning have as fast, will burn about the same amount fuel for the same amount of power output (brake specific fuel consumption); The bigger engine will have higher internal friction and quench area, but smaller vacuum losses as the valves are bigger (I think, it's been a long time since I looked at this stuff in detail). The biggest reason for smaller engines with higher specific output is that with a lighter engine, the rest of the car can also be lighter. A pound off the engine yields many pounds saved for the entire car. And that reduces fuel consumption a lot, and improves handling greatly. And, a smaller, lighter engine provides more options for packaging, like putting the engine aft of the front axle, or in the rear.

Dan McCosh
05-16-2009, 10:14 AM
Geometry doesn't quite work out to make a swap for an engine twice as big, turning half as fast, but generally that's the case. One way to look at it is that IC engines are air pumps--you can make a small pump keep up with a larger one in moving a given volume of air, but it is simpler to make the pump larger.

Tylerdurden
05-16-2009, 10:18 AM
BSA made a 441 cc single-cylinder.

I had a Trophy Trail 500. Put, put :D

pipefitter
05-16-2009, 01:48 PM
Chad, you do know that the phrase was for comparison of small block vs. big block American V-8 production cars with the HP/weight ratios of the time? Also, a good deal of technology with either form was limited because the insurance industry had their grubby little say in the matter as well. A few models had to be "underrated" as was the case with the stage 3 Buick and the LS-6 series from Chevrolet.

The small blocks gained notoriety on the street because average street conditions favored the high revving quick motors over the big blocks who needed room to flex all of those cubes for something other than tire smoke. Then there was the matter of what could be fit under the wheel wells in the way of rubber on production cars while still being able to interchange much of the parts for common grocery get'rs without having to support a completely different entity for racing. Most of the muscle cars had the same sheet metal for mom/pops 6 cylinder family car too and to maintain a sustainable/affordable warranty program as well. These manufacturers, above all, needed to stay in business long term as well while keeping sight of such a varied market.

As far as begging ET's out of massive displacement motors. I knew of an Olds Cutlass with a 350 ci motor that would run high 12's in the quarter with nothing other than a Holley double pumper and tube headers and a dual point distributor while dispatching a few of it's bigger cube competitors on the street.

American iron wasn't lacking performance capability/technology by design as much as it was by the boundaries and legal implications of building death traps for youthful drivers. In most cases, the parents from the "practical" era mindset had to be sold too. They really did a great job of covering the market on average while essentially keeping it affordable for such a long time.

Awwwww. . .c'mon dad, it's only a 289. That's only 89 more inches than your 6. :D

Captain Blight
05-16-2009, 01:56 PM
I do know that a '76 Ford Granada could be made to pick up a few HP on the butt-dyno and sound like totally badassed with the simple modification of flipping the aircleaner cover upside down.

Bought a Holly 600 from a friend along with the manifold and installed it. Dad was all, "Hey that tune-up you boys did was a good job, it really woke it up"


Yeah, Dad, it was the new spark plugs.

Saltiguy
05-16-2009, 03:07 PM
Someone mentioned Outboard engines and it reminded me of an article in a car racing mag back in the 60's(?)
A guy had taken a Mercury outboard powerhead, put it in a racing car (roadracing) and was mopping up the competion.