A difference, to be a difference, has to make a difference --Dr. Michael Korpi, Baylor University
The above is an insightful bit of wisdom from our favorite professor. What Dr. Korpi was saying, of course, is if something has to be changed, it sure as hell better be different and better when you're finished. Nissan could learn a thing or two from Dr. Korpi.
During the last five months, we've driven five examples of the new Sentra SE-R Spec V. That's right, five. We've performed our full gamut of instrumented tests on one car, re-tested the acceleration performance of another and had three on the dyno. Why so many? Because all five failed to accelerate quicker than the lowly Sentra SE we tested in the April '01 issue.
Oh yeah, it's an interesting tale. Read on.In the October 2001 issue, we reviewed the driving characteristics of the much-anticipated, 180-hp Sentra SE-R Spec V. If you remember, we said the car was eager and may be more confidence-inspiring than the famed Acura Integra Type R. What the story lacked, however, were the oh-so-important test numbers by which a performance car lives or dies.Why was that? Well, because we thought the numbers we ran in the car, which was a very early prototype, were bogus. Honestly, we figured the car we had was horribly out of spec, and the last thing we want to do is report suspicious test numbers. If you haven't noticed, we take testing cars very seriously around here.
Anyway, the car we tested, felt strong on the road. Its torquey engine and exceptionally short, close gears fooled our backsides. Then we took the car to the track. Unbelievably, it was slower than the last SR20DE-powered Sentra we tested. That car hit 60 mph in 7.8 seconds and ran the quarter-mile in 15.7 What's more, on our in-house Dynojet chassis dyno the SE-R made only 142 hp and 153 lb-ft of torque. Drivetrain losses aside, any engine rated at 180 hp and 180 lb-ft of torque, which Nissan was claiming for the car at the time, should make more than 142 hp on the chassis dyno. Case in point: The 2001 Acura Integra GS-R carried a factory claim of 170 hp and turned 150 hp on our dyno.
This, of course, sent Nissan's engineers into a head-rolling quest for horsepower and put Nissan's PR department at DEFCON 1. They said we would have a production-ready model to test in a few weeks.Meanwhile, the first car started consuming large amounts of oil and producing clouds of blue smoke from the tailpipe during hard acceleration (see sidebar). Thinking the first car may have been sick from the get go, we told Nissan of the problems as we returned the car and asked for another car to confirm our dyno numbers. Nope, the second car turned the rollers to exactly the same numbers.
A month later, our "production ready" test car showed and we immediately went to the test track. We couldn't believe it. The car was only an eyelash quicker than the prototype. It ran from 0 to 60 mph in 7.8 seconds and covered the quarter mile in 15.7 seconds at 87.4 mph.
Then it produced the most inconsistent dyno numbers we've ever seen from a stock car with a normally aspirated engine, with its peak horsepower and torque figures varying as much as 3.3 hp and 6.9 lb-ft between runs. Because of this sporadic behavior, we took an average of all the runs we recorded. The production engine produces 141 hp and 150 lb-ft of torque. That's 1 hp and 3 lb-ft less than the prototype.
Nissan's revised power claim of 175 hp at 6000 rpm is more realistic than the original 180-hp claim, but is still a long way from the 141 hp produced on the dyno. Our experience with the drivetrain loss varies greatly (see "Technobabble," page 22), but it seems unlikely any front-drive transaxle could make 34 hp evaporate into thin air.
Even more important is how this inconsistency reflects in our earlier review of the car's chassis and engine. That the Spec V will come to market with a torquey engine and a close-ratio gearbox seems certain. But, having driven five SE-Rs, both prototypes and "production" cars, we've noticed significant differences in suspension tuning. It seems impossible to know how the final calibration will be handled.
Here's what we know for sure: As of this writing, the new SE-R impresses us on several levels. First, despite the varied suspension calibrations, all the cars we've driven have exhibited impressive grip. Our most recent test car produced a respectable .84g on the skidpad and zipped through the slalom at 67.6 mph--exactly the same as the last Integra Type R we tested. Second, the new car is quick up any steep, twisty mountain road. So quick, in fact, it bested Acura's new RSX in an impromptu run to the top of our favorite local hillclimb. Credit the close gears, big rubber and very necessary helical limited-slip differential for that feat. However, we did witness some brake fade during the excursion--a problem that didn't exist on the RSX.
Nissan tells us it has a few minor changes planned for the car from what you see on these pages. Those include a revised shifter (good riddance to the hard plastic knob) and a reworked shift action. The Spec V badge, which currently resides on the trunk, will move to the front doors. The gauges will also be made easier to read and the SE-R logo will be removed from the instrument panel. The most important change, however, is the price. While our previous best guess was about $19,000, Nissan just announced they would sell the Spec V for a very reasonable $16,900. We see an inevitable comparison test with the SVT Focus and Civic Si on the horizon.
If all goes as planned, the new SE-R will go on sale about the time you read this.
We don't know if Nissan will find any power in the SE-R's QR25 powerplant before then, but one thing is for sure: Dr. Korpi won't be buying one.
|2002 NISSAN SENTRA SE-R SPEC V |
|Price : Approx. $16,900 |
Engine Code : QR25DE
Type : Inline four, aluminum
block and head
Valvetrain : DOHC, four valves per cylinder, VTC variable intake cam timing.
Displacement : 2488cc
Bore & Stroke : 89.0mm x 100.0mm
Compression Ratio : 9.5:1
Horsepower : 175 hp at 6000 rpm
Torque : 180 lb-ft at 4000 rpm
Redline : 6100 rpm
Layout : Transverse front engine,
1 : 3.417:1
2 : 1.944:1
3 : 1.258:1
4 : 0.947:1
5 : 0.773:1
6 : 0.630:1
Final drive : 4.429:1
Differential : Helical limited slip
Chassis Code : B15
Curb Weight : 2743 lbs
Weight Distribution F/R : NA
Overall Length : 177.5 in.
Wheelbase : 99.8 in.
Overall Width : 67.3 in.
Track F/R : NA
Height : 55.5 in.
Front : MacPherson Strut
Rear : Multi-Link Beam
(twist beam axle with two
trailing links and one Scott-
Russel lateral locating link)
Front : 11.0-inch vented discs,
single-piston sliding calipers
Rear : 9.1-inch solid discs,
single-piston sliding calipers
Wheels and Tires
Wheels : 17 x 7-inch, 47mm-offset
Tires : 215/45ZR17 Continental
Conti Sport Contact
Quarter Mile Time : 15.7 sec
Quarter Mile Speed : 87.4 mph
0-30 mph : 3.1 sec
0-60 mph : 7.8 sec
30-50 mph : 2.6 sec
50-70 mph : 4.4 sec
Slalom Speed : 67.6 mph
Skidpad : .84g
60-0 stopping distance : 126 ft.