Toymods Car Club Inc: General Car Talk => 4cyl Vs 6 cyl (same displacement)

Toymods Car Club
www.toymods.org.au

F.A.Q.

Home

Members

Toymods » General Car Talk » 4cyl Vs 6 cyl (same displacement) Show: Today's Posts :: Show Polls Email to friend

Author

Topic

Shraka
Forums Junkie

Location:
Melbourne
Registered:
November 2003

Re: 4cyl Vs 6 cyl (same displacement)	Sun, 26 December 2004 17:34

When you talk about a car having good torque, what you really mean is it has good low down power, as torque only rotates the crankshaft and power is what moves your car. A road car needs low down power to make it useable. I mean where do most people spend all their time? Up to about 3000rpm? That's why VTEC, VVT-i and other variable timing/advance/lift methods are popular. You can have a car tuned for low RPM, and high RPM. If you got a 2000cc 4 cyl engine, then get another one and attached 2 extra cylinders then reduced the stroke to 2000ccs again, the engines should produce the same power. The 6 would be smoother, but the 4 would have better power to weight as it's lighter (And thusly giving a better front/rear weight balance for your car). If you then however, re-adjusted the redline on the 6 cylinder, you should find it can rev out a little higher now, and thusly will make more power, and so you should re-design the head and crankshaft for this, thusly making the two engines totally different again. All things being equal, the 6 cylinder should make more power, similar torque, and rev higher, while the 4s advantage will be weight. Look at engines like the Ferrari 3.6 liter V8 that makes it's max power of 294kw at a heady 8500 rpm. It achieves this by having a bore of 85mm and stroke of 79mm, not to mention a whole host of technology such as variable valve timing and strong internals to take the high RPM. To compare, a SR20 has a bore x stroke of 86 x 86, as does the 2JZ and 3S, and a 4A-GE has 81 x 77. Anyway, that's a pretty high RPM to be having your power band, but it still has good drivability, as it's max torque is 373nm at 4750rpm which is equal to 185kw at 4750rpm. All that pushes only 1350kg of car. Once again, to compare a R33 Skyline GTS-T has 183kw and weighs in at 1360kg. Similar power to weight figures, however the Ferrari makes it at max torque, then goes on to make a shit load more power. A dyno shows you power figures of the engine, not how well the whole car performs. There is a test that can be done to show acceleration. Go to the track and whip out some Quarter Mile times. That's a good test of acceleration. End rant. Edited: Damned Word and it's not using standard apostrophe characters. [Updated on: Sun, 26 December 2004 17:36] [Report message to a moderator]

[Message index]

-=] Back to Top [=-

Current Time: Thu Jul 31 11:41:54 UTC 2025

Total time taken to generate the page: 0.0044300556182861 seconds

.:: Contact :: Home ::.