Corvette C6 Topgear Track time.

[graywolf624]

As far as the Corvette engine goes, the pushrod design is old and frankly outdated,

As I stated above.. Pushrod is actually newer then overhead cam. May want to rethink that arguement.

you want is because of engine size, bigger the engine, higher the weight, that can be somewhat contained by using Aluminium, as in the Corvette's engine, but still, a big engine as in the Corvette made it have some design compr

This is incorrect. Even ignoring alluminum cams can make up for the weight difference. See the 5.0 versus 4.6 I mentioned earlier. Also that alluminum ls1 is one of the lightest engines out there.
Please rethink your args.

and space

Not true of space either. Interior hp/liter does no correlate directly with engine bay space.

variable valve timing and lift,

They have that technology for pushrods as well.

As for bigger engines being smaller? If you take modern engines, a smaller displacement engine is going to be smaller. Obviously this varies from manufacturer to manufacturer.

Errr.. wrong...

You're right though HP/litre doesen't effect anything when u consider it on your own - did i ever say it didnt? I said it was a good statistic to use when comparing engines.....

Why? Why is it a good statistic for comparing engines. It shows nothing in a real world. Not a damn thing. Thats like saying the color is good statistical comparison for engines. IT doesn't mean anything.

Less mass dosen't neccesarily mean more acceleration. It's alos how you put the power onto the road. Hence why 4WD cars are usually faster off the line.

Yes it does.. Acceleration isnt just from the start line. Less mass will always result in faster somewhere.

[mindgam3]

[quote="graywolf624"]

As for bigger engines being smaller? If you take modern engines, a smaller displacement engine is going to be smaller. Obviously this varies from manufacturer to manufacturer. Errr.. wrong... You're right though HP/litre doesen't effect anything when u consider it on your own - did i ever say it didnt? I said it was a good statistic to use when comparing engines..... Why? Why is it a good statistic for comparing engines. It shows nothing in a real world. Not a damn thing. Thats like saying the color is good statistical comparison for engines. IT doesn't mean anything. Less mass dosen't neccesarily mean more acceleration. It's alos how you put the power onto the road. Hence why 4WD cars are usually faster off the line. Yes it does.. Acceleration isnt just from the start line. Less mass will always result in faster somewhere.

lol, how can you say that a bigger displacement means a smaller engine??
Maybe its true for some cars, but for the majority its not. For example I have a clio 1.2, their is so much space in the engine bay. All the renault clios with a bigger displacement; 1.4, 1.6 I can physically see less space in the engine bay the bigger the engine displacement gets....

If you compare the same engine but with only bigger displacement, its almost always going to be bigger.

As for the HP/litre thing, im not going to bother arguing any more, its pretty much pointless. All i'm going to say is that if enginneers, the people who actually design engines in the first place actually use them then it must be of some use. For reasons i have already explained i think it is too.

As for the mass, you're definately wrong, less mass will NOT neccesarily mean faster acceleration. It comes into it, but isn't the whole story. If two cars, one weighing 1200kg, and one 1300kg, they both have exactly the same power output. If the 1300 car has significantly more traction, its always going to out accelerate the lighter car.

If i have an extreme example, two cars, one weighing 500kg, the other 2000kg, both with the same engine. But the lighter cars has wheels made out of ice (or a material with similar friction properties) and the 2000kg car has super soft racing slicks on. Which one is going to accelerate faster??

[LotusGT1]

Originally Posted by Guibo Originally Posted by LotusGT1 @Guibo. Laptimes between a Z06 and the GT3 are compared. The comparison between the laptimes of the C6 and the GT3 were purely based on misinformation by some guys here. Fair enough. I do find it interesting that lap times to the exact second are being debated on cars driven on different days by different drivers...on a 13-mile track.

I made that same point.

Originally Posted by Guibo Originally Posted by LotusGT1 Nevertheless, calling a Porsche 911 GT3 a limited-edition, hand-made, premiere, no-holds-barred, no-expense-sparred, trimmed-down, light-weight, racer-wannabe uber-sportscar is comical, and couldn't be farther from the truth. Childish might be a better word. It is indeed limited (only 750 samples will make their way to the States this year). Even if the GT3 RS more accurately fits the description, it doesn't mean the GT3 is not a narrowly focused track-oriented car as well. There are numerous, substantial changes to the GT3 over the standard 996 that make it considerably more track-worthy.

If you would have read all the posts you'd see I have trouble with the derogatory racer-wannabe comment.

But I think we can all agree this whole debate is purely based on preferences. All cars mentioned are very capable in their own way.

[LotusGT1]

Originally Posted by RC45 Originally Posted by LotusGT1 Originally Posted by TT Nope, also Swiss ppl gives a crap about it too many cubic centimeters causes higher takes so a hypedout 500 cc engine boosting out those 400 hp would be ideal here Yes, I know the GT3 doesn't go. The car laps the 'Ring in 7:54...but you're right, it doesn't go :roll: Damn... Talk about "Quick Draw"... You just gunned TT down...

LOL, just realised I quoted the wrong guy

It was a reaction to this post:

Originally Posted by T-Bird If you know anything about what makes a car go it's called Torque and that seems to be something that the GT3 doesn't have, or many Porsches for that fact.

[graywolf624]

lol, how can you say that a bigger displacement means a smaller engine?? Maybe its true for some cars, but for the majority its not. For example I have a clio 1.2, their is so much space in the engine bay. All the renault clios with a bigger displacement; 1.4, 1.6 I can physically see less space in the engine bay the bigger the engine displacement gets....

How? Because the size of the actual cams. see the 5.0 versus 4.6
Hell see the 5.7 ls1 versus the 5.4 in the ford gt.

enginneers, the people who actually design engines in the first place actually use them then it must be of some use

They don't use them. Trust me, I know some of them at ford and gm. Its a number the mags and ricers use. Thats about it.

As for the mass, you're definately wrong, less mass will NOT neccesarily mean faster acceleration. It comes into it, but isn't the whole story. If two cars, one weighing 1200kg, and one 1300kg, they both have exactly the same power output. If the 1300 car has significantly more traction, its always going to out accelerate the lighter car.

You dont understand what i said apparently. Acceleration doesnt have to mean from a stop. Or even from a point were traction would ever be an issue. The fact is a lower mass car will always accelerate faster at some point in its drive.

But the lighter cars has wheels made out of ice (or a material with similar friction properties) and the 2000kg car has super soft racing slicks on. Which one is going to accelerate faster??

Now your getting rediculous bud. Take a better comparison.. Street tires versus slicks. Same car but 100 pounds lighter.. from 60 mph... The lighter car will accelerate faster. The only way it wouldnt would be traction.. But then lets move up to 100 mph.. at some point traction isnt the issue (Cars arent that rediculous in speed). At that point mass always directly influences acceleration.

Hell.. in fact mass influences traction too.
Mass and hp are important.. Fuel economy is important.. Hp/liter isnt.

[mindgam3]

Originally Posted by everso Originally Posted by graywolf624 Mass and hp are important.. Fuel economy is important.. Hp/liter isnt. you've sort of trapped yourself with that statement. although i agree with you that Engineers probably don't sit around talking about HP/Liter statistics....things like weight, mass and fuel economy (things you admit are important) *are* influenced by the liter size of the engine. Engines can add significant weight and mass to a car. I think it's also safe to say that fuel economy is inversely proportional to the size (in Liters) of an Engine. (the exception being the Rotary engine, which doesn't correspond to normal liter numbers) to get maximal power per liter would technically make sense, since one would be trying to add the least weight and least sacrifice to fuel economy while still adding power. I can see what both sides of this debate are saying...the answer lies between.

I agree, somewhere in between

Although im not saying HP/litre is the most important statistic for and engine, and its not neccesarily used in the designing of engines but is used to compare engines and gives a fairly good picture of the engines performane.

[RC45]

Originally Posted by LotusGT1 Originally Posted by Guibo Originally Posted by LotusGT1 @Guibo. Laptimes between a Z06 and the GT3 are compared. The comparison between the laptimes of the C6 and the GT3 were purely based on misinformation by some guys here. Fair enough. I do find it interesting that lap times to the exact second are being debated on cars driven on different days by different drivers...on a 13-mile track. I made that same point.

This is the very point many of us have made for years - but it falls on deaf ears when the parties are trying to "defend" their point of view.

As stated before, local track knowledge is MORE important than the car on a track as complex as this - with cars so close in performance.

[RC45]

Originally Posted by mindgam3 Originally Posted by everso Originally Posted by graywolf624 Mass and hp are important.. Fuel economy is important.. Hp/liter isnt. you've sort of trapped yourself with that statement. although i agree with you that Engineers probably don't sit around talking about HP/Liter statistics....things like weight, mass and fuel economy (things you admit are important) *are* influenced by the liter size of the engine. Engines can add significant weight and mass to a car. I think it's also safe to say that fuel economy is inversely proportional to the size (in Liters) of an Engine. (the exception being the Rotary engine, which doesn't correspond to normal liter numbers) to get maximal power per liter would technically make sense, since one would be trying to add the least weight and least sacrifice to fuel economy while still adding power. I can see what both sides of this debate are saying...the answer lies between. I agree, somewhere in between Although im not saying HP/litre is the most important statistic for and engine, and its not neccesarily used in the designing of engines but is used to compare engines and gives a fairly good picture of the engines performane.

You guys still need to admit that bigger displacment push-rod engines are lighter and smaller than smaller displacement OHC models of similar layout.

[mindgam3]

Originally Posted by RC45 Originally Posted by mindgam3 Originally Posted by everso Originally Posted by graywolf624 Mass and hp are important.. Fuel economy is important.. Hp/liter isnt. you've sort of trapped yourself with that statement. although i agree with you that Engineers probably don't sit around talking about HP/Liter statistics....things like weight, mass and fuel economy (things you admit are important) *are* influenced by the liter size of the engine. Engines can add significant weight and mass to a car. I think it's also safe to say that fuel economy is inversely proportional to the size (in Liters) of an Engine. (the exception being the Rotary engine, which doesn't correspond to normal liter numbers) to get maximal power per liter would technically make sense, since one would be trying to add the least weight and least sacrifice to fuel economy while still adding power. I can see what both sides of this debate are saying...the answer lies between. I agree, somewhere in between Although im not saying HP/litre is the most important statistic for and engine, and its not neccesarily used in the designing of engines but is used to compare engines and gives a fairly good picture of the engines performane. You guys still need to admit that bigger displacment push-rod engines are lighter and smaller than smaller displacement OHC models of similar layout.

ahhh you see, no one ever stated that. graywolf said that bigger displacement engines are generally smaller than smaller displacement engines which makes no sense at all. I agree push rod engines are smaller and generally lighter than the equivalent OHC models, but they have more moving parts than pushrod engines.

Originally Posted by graywolf624 As I stated above.. Pushrod is actually newer then overhead cam. May want to rethink that arguement.

It may be the older technology, but if you want performance and tunability, OHC is the best way to go as you can rev much higher and they generally produce more power compared with the equivalent pushrod engine

[RC45]

Originally Posted by mindgam3 ahhh you see, no one ever stated that. graywolf said that bigger displacement engines are generally smaller than smaller displacement engines which makes no sense at all. I agree push rod engines are smaller and generally lighter than the equivalent OHC models, but they have more moving parts than pushrod engines.

Listen to yourself.

You are now contradicting yourself.

graywolf quite clearly qualified (as EVERY push-rod supporter did) that the larger displacement pushrod engine is smaller than the equivalent OHC cam model.

You are just trying to back out of you point of view now.

This is your comment:

Originally Posted by mindgam3 lol, how can you say that a bigger displacement means a smaller engine?? Maybe its true for some cars, but for the majority its not. For example I have a clio 1.2, their is so much space in the engine bay. All the renault clios with a bigger displacement; 1.4, 1.6 I can physically see less space in the engine bay the bigger the engine displacement gets.... If you compare the same engine but with only bigger displacement, its almost always going to be bigger.

You clearly never read a a word any of the push-rod supports typed.

To a T they ALL made the comaparion between larger displacement push-rod engines and smaller displacement OHC models.

You lathced onto the "larger displacment of same engine type" thought - and you projected this on their points of view.

[mindgam3]

Originally Posted by RC45 Originally Posted by mindgam3 ahhh you see, no one ever stated that. graywolf said that bigger displacement engines are generally smaller than smaller displacement engines which makes no sense at all. I agree push rod engines are smaller and generally lighter than the equivalent OHC models, but they have more moving parts than pushrod engines. Listen to yourself. You are now contradicting yourself. graywolf quite clearly qualified (as EVERY push-rod supporter did) that the larger displacement pushrod engine is smaller than the equivalent OHC cam model. You are just trying to back out of you point of view now.

I'm not backing out of any of my comments. sorry, i did mis read the OHC vs pushrod

My point of view on the OHC vs OHC is as i said:

Originally Posted by mindgam3 It may be the older technology, but if you want performance and tunability, OHC is the best way to go as you can rev much higher and they generally produce more power compared with the equivalent pushrod engine

I havent contradicted myself though, i never compared OHC to pushrod before my last post.

[Guibo]

Originally Posted by mindgam3 If all things stay the same, increasing the displacement WILL increase the power. I never said that the relationship between Displacement and output power was linear, but its the general trend. Obviously theres limitations.

I meant all things being equal in the sense of how much $$$ do you want to invest in the engine, how much stress do you want it to be under, what's the projected durability you're looking after?
Could BMW or Ferrari have developed a 6.0-liter engine making 120 hp/l like Honda's S2000? Perhaps not under their budgets. But with unlimited funds, sure, they could have done it. Would it have been practical? No. Both those engines surely make enough hp and torque for their intended applications.
Back to the S2000, the '04 S2000 actually makes less hp/l than the older ones. And according to most road tests, it gives up nothing in performance. Most road tests actually indicate better overall driving dynamics, with regard to perceived throttle response, in-gear acceleration, etc. In countries with displacement taxes, or racing series with strict displacement limits, hp/l is very important. But just because something works out the best for Formula One does not necessarily mean you'd want the same thing in your daily driver.

[RC45]

Originally Posted by mindgam3 Originally Posted by RC45 Originally Posted by mindgam3 ahhh you see, no one ever stated that. graywolf said that bigger displacement engines are generally smaller than smaller displacement engines which makes no sense at all. I agree push rod engines are smaller and generally lighter than the equivalent OHC models, but they have more moving parts than pushrod engines. Listen to yourself. You are now contradicting yourself. graywolf quite clearly qualified (as EVERY push-rod supporter did) that the larger displacement pushrod engine is smaller than the equivalent OHC cam model. You are just trying to back out of you point of view now. I'm not backing out of any of my comments. sorry, i did mis read the OHC vs pushrod My point of view on the OHC vs OHC is as i said: Originally Posted by mindgam3 It may be the older technology, but if you want performance and tunability, OHC is the best way to go as you can rev much higher and they generally produce more power compared with the equivalent pushrod engine I havent contradicted myself though, i never compared OHC to pushrod before my last post.

Oh ok..

But we are all comapring push-rod to OHC...

[mindgam3]

Originally Posted by Guibo Originally Posted by mindgam3 If all things stay the same, increasing the displacement WILL increase the power. I never said that the relationship between Displacement and output power was linear, but its the general trend. Obviously theres limitations. I meant all things being equal in the sense of how much $$$ do you want to invest in the engine, how much stress do you want it to be under, what's the projected durability you're looking after? Could BMW or Ferrari have developed a 6.0-liter engine making 120 hp/l like Honda's S2000? Perhaps not under their budgets. But with unlimited funds, sure, they could have done it. Would it have been practical? No. Both those engines surely make enough hp and torque for their intended applications. Back to the S2000, the '04 S2000 actually makes less hp/l than the older ones. And according to most road tests, it gives up nothing in performance. Most road tests actually indicate better overall driving dynamics, with regard to perceived throttle response, in-gear acceleration, etc. In countries with displacement taxes, or racing series with strict displacement limits, hp/l is very important. But just because something works out the best for Formula One does not necessarily mean you'd want the same thing in your daily driver.

Hondas S2000 engine is indeed a great one, honda make extremely good engines. And you've got to admit 110hp/l from ferraris enzo is pretty good. As I said, the general trend between power and dislacement is roughly linear, but I agree with you the greater the displacement, the harder it is to get the same amount of power per litre, plus they're are limitations.

I do think you're contradicting yourself though by comparing engines with HP/l and then implying its not important other than countries with displacemtn tax or racing series with strict displacement limits. People are saying HP/litre is useless for comparing engines and then here Guibo is using it to put forward an arguement....

[mindgam3]

Originally Posted by RC45 Oh ok.. But we are all comapring push-rod to OHC...

lol, thank you, i'm back on track now