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Straight 6 Vs V6

Jack-

By Jack-,
in General Automotive Discussion

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Kinks Grand Master

Kinks

Posted
Posted
And to Kinks,

the reason F1 cars rev to 18k+rpm is that they are limited to a very small capacity.

Yep, I'm aware of that. And yet the more they limited capacity the more lap times stayed the same, because the RPMs went up to compensate (until they put a cap on engine revs). Just illustrating the point that "RPM means nothing" is complete bull.

R338OY Veteran

R338OY

Posted
Posted (edited)
The "GT" designation stands for "Gran Turismo" or "Grand Touring". Skylines were built as enduro racers, not dropping down to the shops to get some milk. A Hyundai Excel is a road car.

Again, Skylines are road cars. If Nissan built an 'enduro racer' the first thing they'd have done is fitted a dry sump to the GT-R (like a racer would have) to fix it's oil failure problem. It comes from Nissan as a road car, with road car bits on it. Yes, it's design originates from a racing car, but that's not what Nissan is selling on the showroom floor.

What's usable torque going to achieve if you have to change up a gear at 3,000RPM? When was the last time you were out-dragged by a bus? Why do you think F1 cars rev to the sky rather than rely on bottom end torque?

It's all down to gearing. It's better to make torque at high RPM because you can be in a lower gear, and the effective torque at the wheels is better.

Ok. A bus is unrelated to a Skyline, or the topic.

Who'd change gears at 3000RPM? Peak torque is later than that on stock Skylines.

F1 cars need high RPMs because their torque is available much higher up than a Skyline, plus they're NA.

Yes, it's down to gearing and not how many RPM's you're able to hit. I don't see how being in a lower gear means you'll win a race if peak power is the same. But you're going off topic, from engines to drivetrains, and making yourself look cockish.

90L engine? hahahaha.. you're kidding right. I think you mean 9.0L. Most prime movers use turbo diesels around the 9.0L mark (eg Volvo FM-9 prime mover is 9.4L turbo diesel). Don't pull figures out of your arse.

That's all you've got? You're picking at a dot? I'll remind myself when i see a mistake in your posts that you're the dot guy :P

yeah the long crank in the straight 6 never causes problems. thats why rb motors never have problems with bent cranks, cracked oil pumps or spun bearings.

Yep they do. You're referring to high powered engines right?

And you are right, it is all down to gearing, but that same principle applys to low revving cars aswell, just look at the Audi diesle Le Mans race car, it wont even pull 5,000rpm, but thanks to clever gearing the thing is increadibly fast. But this is all off topic.

:unsure:

Yep, I'm aware of that. And yet the more they limited capacity the more lap times stayed the same, because the RPMs went up to compensate (until they put a cap on engine revs). Just illustrating the point that "RPM means nothing" is complete bull.

Racing engines, Formula 1 technology and regulations relate to straight and V6's how? You've lost me.

One thing you're great at doing Kinks, is taking what someone says out of context and throwing a heap of sh!t at it.

I was trying to flip the coin on your earlier comment, talking about torque curves in straight 6's and circuit racing a Skyline. You threw Formula 1 into the debate to compensate for a poor argument.

Edited by R338OY
scathing Grand Master

scathing

Posted
Posted
ive like to see a v6 of equal capacity makin 1500hp+ lol

There's an 1800hp VQ35DE seeing duty in a tube frame drag car in the USA.

While it has an extra half a litre of displacement to make its extra 300hp, the engine is also far newer than a 2JZ in a sports car platform and so has nowhere near the amount of R&D time being poured into it.

VB- Veteran

VB-

Posted
Posted

2jz's have gone over 1800 i think. one guy, 'marko' made over 1500rwhp in his street car. the shop that built it basically told him 'let us wind the boost right up (was like 59psi) and make it go bang, to find its weak point' but it didnt let go... just made stupid power

Kinks Grand Master

Kinks

Posted
Posted
Yep they do. You're referring to high powered engines right?

You completely missed Duncan's sarcasm...

You're welcome to your own opinion, but FWIW you are much closer to the mark with "it doesn't matter, so long as peak power is the same" rather than your earlier comment about it all being about "usable torque".

R338OY Veteran

R338OY

Posted
Posted
You completely missed Duncan's sarcasm...

You're welcome to your own opinion, but FWIW you are much closer to the mark with "it doesn't matter, so long as peak power is the same" rather than your earlier comment about it all being about "usable torque".

I did get the sarcasm. You didn't get mine.

Well Geoff it looks like we've reached some kind of consensus :)

Cheers

TiTAN Grand Master

TiTAN

Posted
Posted (edited)

Inline engines tend to make more torque than their V counterparts, hence why most truck engines are an inline 6/8cyl

As far as the truck engines go. You can get a 15L or so engine if you get a large prime mover.

Edited by TiTAN
GTR-32U Mentor

GTR-32U

Posted
Posted

What's usable torque going to achieve if you have to change up a gear at 3,000RPM? When was the last time you were out-dragged by a bus? Why do you think F1 cars rev to the sky rather than rely on bottom end torque?

B12BLECC001.jpg

Hey I drive one of these......You would be surprised how well the newer ones accelerate when they are up on boost....specially up a hill...I get lots of 4 bangers pinging next to me climbing hills...trying to keep up

scathing Grand Master

scathing

Posted
Posted

A bus also weighs a fair amount more than a car, so its not really a relevant comparison.

If you compare two similar cars (for example, the BMW X5 3.0si petrol vs 3.0 sd diesel), they make the same power but the diesel makes far more torque. Even though the diesel carries more weight, has a higher drag coefficient, and a far lower redline, its still significantly quicker.

F1 cars rev to the sky because they're limited to normal aspiration and a certain displacement. Without boost or cubes, the only way to get power is through revs.

gtst25 Proficient

gtst25

Posted
Posted
2jz's have gone over 1800 i think. one guy, 'marko' made over 1500rwhp in his street car. the shop that built it basically told him 'let us wind the boost right up (was like 59psi) and make it go bang, to find its weak point' but it didnt let go... just made stupid power

Gas motorsports are making over 2000 hp out of the 2jz

http://www.youtube.com/watch?v=LpFRBc0ZdoE

Commodore v6's are a woeful example of engineering. Hmmmm pushrods, 2 valves per cylinder BALANCE SHAFTS as the engine is so out of balance in this age??? Piss poor. LIving in the 60's. Crap.

I haven't had anything to do with the new 'alloytech' engines. Not holding my breath though...

Depends on who makes the engine really - rb's are a very well made engine - same goes for the 2JZ's. I'm sure nissan make nice v6's although a pain in the arse to work on. Hell the new gtr runs 11's standard - I bet you'll see good engineering with their engine... Not a pushrod in sight.

Cheers

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