S2000 Powered Bentley?!
Thankyou for your article on power v torque. I now understand the basic concepts of how torque, power and rpm are related - though I still have some questions when comparing a high power, low torque engine to a high torque, lower power engine. For example... The 1989 Bentley Eight has a huge 6.8-litre V8 that, I read, has 420Nm of torque and surprisingly low 154KW of power. I found this odd so I went on the web found your great site, did the math and concluded it must rev to only about 3200 rpm!
Now let's take Honda's 2.0-litre engine from the S2000 that develops 176kW at 8300 rpm and therefore has 203Nm (they claim 208Nm) and stick it into a big heavy Bentley. Drag it against the standard Bentley and which would win? On paper the one with more power should win, but in real life I don't see how a revy little 2.0-litre could pull a 2-tonne car faster than a big V8 with a truckload of torque.
Andrew McCluskey
Australia
Wow - here's an interesting one!
Gearing would play a major part in determining the standing start performance of the S2000 engine'd Bentley; if the gearing were too tall, it might take several seconds just to get the 'revy little motor' up to the zone where it has a power advantage. We imagine the necessary gearing would be so short and closely stacked you'd need to make a multitude of gearchanges on sprints to, say, 100 km/h; the gearshifts themselves would cause their own time loss. The Bentley, therefore, would probably win.
In rolling times, though, the VTEC motor could easily be zapped up to around 8000 rpm (with the right gearing) and, yes, it would pull away from the less powerful but torquier Bentley motor.
Not Fair on IS300
I was reading your review of the Lexus IS300 and, I have to admit, I strongly disagree with your opinion of the car. Well, actually, there are some areas where I agree with you. Granted, yes, the IS300 does not offer the greatest performance but it does provide more then enough when all things are considered. For example, for its weight, it's impressive the IS300 goes 0-60 miles per hour, (forgive me, living in the 'States I'm not used to using the metric system) within the 7-second range. Also, it is impressive that such a heavy vehicle does a quarter mile in the 15-second margin.
The handling on the car also deserves more credit then you gave it. I own one myself and I have no problem drifting the corners with my car; I've had my car for over a year now and I can tell you this.
By the way you wrote your article you went in expecting a Ferrari and received a Honda. I respect your credentials sir, but with all due respect, the IS300 is far from forgettable. In Japan, it's called the Altezza for a reason and continues to create a large spark in the Import world. This car is a lot of fun to drive, to race and especially to modify. I ask that you reconsider your review.
Here in the 'States, we have a racing team that uses the IS300 for racing called Pro-Lex Performance. If you have the time, I ask you take a look at their website to see how much this car is capable of. Also, IS300.net provides a lot of helpful information. Lastly, Powerhouse Racing here in Texas has done amazing work with this fine car. Thankyou for your time.
Nick Song
USA
When the IS300 was released in Australia it was supposed to set a new benchmark in its class; perhaps partly due to the early marketing hype, the car never quite delivered all that was expected.
Just take a look at its power-to-weight ratio; it's by no means bad, but neither is it the stuff benchmarks are set with. We could only attain mid-8s 0 - 100 km/h out of our test car, which - for whatever reason - is considerably slower than the 7.4 seconds claimed (for 0 - 60 mph) on the US Lexus website. And, yes, both the Australian and US-spec cars have the same power outputs.
We expect that the tyres fitted to the US-spec IS300 are different to the 215/45 Z-rated Bridgestone Potenza RE040s as fitted to our press car. As such it's probably not a good idea to compare overall grip levels, but note that "drifting the corners" isn't necessarily a pointer to brilliant handling.
Tuning potential of the atmo 2JZ-GE? We haven't seen any of it here in Australia, dammit!
Want Not to Wear
I have a general question relating to engine durability under full acceleration. I own an unmodified S15 200SX that is dealer serviced at 5000km intervals, runs Optimax and never hits the rev limiter (ok, maybe once or twice). Friends often comment that it can't be good to regularly accelerate at full throttle, that engine wear must result. I would appreciate your opinion.
Note - I am careful not to do this after sitting at the lights, in very warm weather or within the first 5 minutes of running. Thanks and keep the great content coming!
Paul Sampson
Australia
As you're obviously aware, it is absolutely critical to 'go easy' on the engine until it is up to normal temperature. We can't emphasise this enough.
Aside from that, though, it must be true that regular full throttle acceleration will cause wear and stress in various areas. Full power acceleration obviously stresses the driveline as well as certain parts of the engine; pistons, rings, conrods, the crank, bearings and various other components are placed under considerable load.
Note, though, different types of stresses are caused by very high revs - valve springs and rocker gear, for example, can often fail.
None of this is to say that a good modern engine can't cope with a bit of WOT. So long as there is proper lubrication, detonation is avoided, mixtures are healthy and everything is operating at the appropriate temperature there shouldn't be any problems with the occasional squirt!
Fully Sik Makes Me Sick!
Your article "A Nissan 300ZX TT that's been treated to absolutely everything!" almost made me sick. If I wanted to see cars like this, I would have a subscription with other magazines. Please steer clear of these 'fully sik' cars and keep with the program of well-engineered purposeful cars.
Filip Petreski
Australia
Not Entirely Happy...
I read with interest the article about head porting; it was very nicely balanced between textual and visual information. One thing I did find lacking, though, was a before and after dyno chart. Measuring the increase in flow (in cfm) is very nice and so is calculating the theoretical max BHP, but I would have liked to read how a porting job will affect the engine. Can a 25% increase in flow increase the torque or BHP by 25%, or is the change barley noticeable on the road? Is a complete remapping needed to take advantage of the increased flow?
I sometimes feel that you have shifted the focus of the magazine from DIY stuff and articles on how one can modify their car (which is what drew me to the magazine in the first place), to new car tests, feature cars, new technology articles and product reviews. The products reviews - which can be for product sold in the AutoSpeed shop - can even be thought of as advertisements. I don't mind you endorsing a product since I value your judgment, but I do miss the "real" article that could have been published instead (I'm referring to the one about how I could turn my 200SX to a 400 BHP road/rally monster by utilising $50 and common workshop tools). It's a shame, because the "new" type of article can be found in quite a few magazines, but few magazines - if any - can do the "old" type like you.
That said AutoSpeed is still one of the best on my list. Best regards.
Avner Bronfeld
Israel
We can understand how it would have been nice to follow up with a before and after power comparison with the ported head, but - in this case - that simply was not possible. The engine was not ours for starters.
As with most engine mods, there's no question an ECU remap would certainly allow the optimal performance to be extracted. Again, though, the engine wasn't ours so we couldn't exactly take it away to run it with both the existing ECU program and a custom tune.
The focus of AutoSpeed has not shifted, but - as you can imagine - there is a finite number of ways to turn a 200SX into a 400hp monster for only $50 using common tools. We have covered many approaches to boost control, air intakes, exhausts, etc and have done many power-up articles relative to the 200SX. And, yes, there will be more to come so stay tuned.
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