Tuned 4/6cyl vs V8

[GSR VTEC 94]

Ive always been curious how a 4 or 6cyl with less HP can hang with beefy V8s (besides the weight factor). I dont wanna sound stupid, because I know theres a ton of factors involved, but it always fascinates me to see a 4 or 6 hang with or even smoke V8's when you would think V8s are unstoppable. Can someone explain whats behind the whole idea of a 'tuned 4cyl' etc and what makes them work so well? Also, would you rather have a 300 hp I4, 6cyl, or V8. What I am trying to get at here is what the actual differences between the WRX STi, Turbo Supra and a beefy V8 like a Cobra are , when they all have around the same HP. One last thing, can someon explain compression ratios. Thanks and hope this all makes sense!

[Rakshas]

Tuned 4 cyls are usually loaded with technology. DOHC, evo is running twin yrubos and 4wd, rally brd tech etc. 6 cylinders are a little closer to v8's in that they have medium size displacements but once again they are loaded with tech. DOHC, supra runs twin turbos and a getrag transmission.

V8's follow the old american formula: there is no replacement for displacement. The lS1 is a rather low tech OHV v8 still running on pushrods. It's large displacement however allows it to generate massive amounts of torque and power.

[3000ways]

Originally Posted by Rakshas

evo is running twin yrubos and 4wd

EVOs only have one turbo. I don't understand what you mean by tuned 4 cylinder/6 cylinder, are you talking a modified car vs. stock ones, then that is not really fair. This thread is just going to beat a dead horse and cause much drama. You have to be more specific, what do you mean when you say hang, are you talking at a drag strip, or on a race track, or on the freeway. Also people it's time we start to update all our old theories, with today's technology, the old theories that were the norm for back in the day, do not come into play most of the time anymore. For example the old, AWD cars lose alot more power to the wheels, please then why are EVOs dynoing between 230AWHP to 250AWHP, in fact a 230AWHP EVO is considered a weak one. STIs have been dynoing between 250AWHP to 260AWHP. Also the whole displacement is the only way to make more power, then please explain Veilside and there street legal 1,360HP Skyline, I'm sure it was stroked to 2.8L-3.0L, still compared to 4.6L-5.7L it's small, but still making 1,360HP. Please find me a STREET LEGAL V8 or V10 making the same power, and if you do, which you may, I'll go ahead and find you 5 or 6 more 1,000HP STREET LEGAL Skylines.

[youngvr4]

if were talking 1000hp v8's compared to 1000hp skylines then you can find lots of lingenfelter corvettes at 1000hp. there were 2 of them in the dupont registry a few months ago

[GSR VTEC 94]

What I mean by tuned is, example, the Type R integra is tuned unlike the LS or RS models, and obviously the WRX is tuned whereas the regular Impreza is not race inspired. I guess I meant more that tuned is meant for racing etc. Make sense? Hope that makes it clear.

[Mr Payne]

Originally Posted by 3000ways

Please find me a STREET LEGAL V8 or V10 making the same power, and if you do, which you may, I'll go ahead and find you 5 or 6 more 1,000HP STREET LEGAL Skylines.

1000hp Street Legal Skyline? They can do that while still obeying emissions regulations? Please, show me some...

The amount of 1000hp Vipers is fairly large. I don't think there are many 1000hp Vettes simply because the LS1 wasn't designed to take huge power and anyone looking for that kind of power will usually go to a different engine choice.

[3000ways]

Originally Posted by Mr Payne

1000hp Street Legal Skyline? They can do that while still obeying emissions regulations? Please, show me some...

The amount of 1000hp Vipers is fairly large. I don't think there are many 1000hp Vettes simply because the LS1 wasn't designed to take huge power and anyone looking for that kind of power will usually go to a different engine choice.

The point is that's it's not just about replacement when it comes to making power, the Skyline clearly illustrates this. Also so do the many 800 to 1000HP Supras.

http://www.superstreetonline.com/fea...ehicles/32699/

[Rakshas]

Sorry about the mistake with the evo's, also I said that the american v8's are built around the displacement Idea. I didn't say it was the only way to make power, nor did I say I believe in it..

[Mr Payne]

Originally Posted by 3000ways

The point is that's it's not just about replacement when it comes to making power, the Skyline clearly illustrates this. Also so do the many 800 to 1000HP Supras.

http://www.superstreetonline.com/fea...ehicles/32699/

Ahh, the point was unclear considering you fully capitalized "street legal". Too many people oversimply the whole "No replacement for displacement" mantra. Large amounts of torque high up in the rev range creates large power. The RB26DETT revs high and creates a large amount of torque with a large turbo. Purely elementary. Vipers create monstrous amounts of torque but don't rev quite as high(which is due to a mulitude of factors, ie: stroke length and pushrod design). Two different philosophies, one is not faster than another.

[Joseph1082]

Ok, you guys may thing I am biased, which I am... ok, power is a function of Force and Time. The more force, the more power, in less time, more power. So speed is also a factor. So what would you rather have... a 300HP engines that makes it's power by reving to 10,000 or a 300HP motor that only goes to 6000 but has double the torque.
Two guys, the first on, it takes him a little while, but he benches 350lb. In that same time, this other guy benches 150lb. several times... do the equations, they both have the same power output, but who would you rather be? I like my car the same.

[TatII]

but you can't use that logic with engines. because if a person can bench 350 lbs once, then the he should be able to bench 150 a good amount more then several times.

sure the large engine can make it lower down. but think of the extra weight of the pistons and rods, and crank. the way to get v8's to make massive power is to rev them to around 8K or 8.5 K. those engines are designed to only rev to 6-6.5K so the increased engine speed with heavier rotating parts makes it just as stressfull to make big power as it does with a smaller engine using boost.

[Mr Payne]

Originally Posted by TatII

but you can't use that logic with engines. because if a person can bench 350 lbs once, then the he should be able to bench 150 a good amount more then several times.

sure the large engine can make it lower down. but think of the extra weight of the pistons and rods, and crank. Not neccesarily true.the way to get v8's to make massive power is to rev them to around 8K or 8.5 K. I think you meant to say "The way naturally aspirated V8s will make a high specific output is by revving to 8K." Currently the LS6 can get to 470rwhp in naturally aspirated form, in street trim. Is that not considered massive power? If you want to talk about boost, there is no reason that larger displacement engines can't use boost as well. those engines are designed to only rev to 6-6.5K so the increased engine speed with heavier rotating parts makes it just as stressfull to make big power as it does with a smaller engine using boost.A supercharged Viper engine can make 600rwhp without breaking a sweat. That's the MAX lower displacement engines can get with non-race fuel.

...

[TatII]

well this was sorta a continuation of the last debate we had. but yes a n/a v8 will making more power saver then a turbo 4. however a turboed 6 like the supra will be more safer then a n/a 8. hp for hp.

[3000ways]

[quote=Mr Payne]Ahh, the point was unclear considering you fully capitalized "street legal". QUOTE]

The car I linked you to is street legal, well in Japan it is.

[Mr Payne]

[quote=3000ways]

Originally Posted by Mr Payne

Ahh, the point was unclear considering you fully capitalized "street legal". QUOTE]

The car I linked you to is street legal, well in Japan it is.

I didn't read street legal anywhere in the article. Perhaps you could quote it?