DavidM

Tonight I 'benchmarked' the Zeds acceleration against a HSV R8. My Zed is barely run-in as I have less than 1200km ... it's still pretty green and I'm sure there'll be more power released with time.

Still, we took both cars out into a quiete long straight steer and did some acceleration tests to see how the Zed compares. I want to see what difference the hi-tect exhaust will make and also I have some the same thing with the S2000 agaisnt a fair few cars (including this exact HSV R8). For anyone who does not know what the HSV R8 is, it starts here are the specs:
- 1705kg,
- 260kW/480nM (HSV claim with good fuel),
- sports suspension,
- 18" wheels 235/35 Pirreelli P-Zero Rosso all the way around
- 345mm cross drilled brakes

This R8 in particular is an Auto (4 speed), but that does not matter much 'cos it has oodles of torque. Accordring to local magazines it does 6.0secs for the 0-100km/h time and 14.0 with 166km/h for the 400m run. Manual beats it by only couple 10th or so. The gearing is 75, 140, 230, 330km/h in each gear (will top at about 265km/h).

So to the results ... they were all rolling-start drags as I did not want the lauch interfering with the actuallt pull that the cars' deliver.

test #1: 10 - 150kph, starting in 1st gear both cars:
The HSV pulled away good 2 car lengths straigh away (ie. before 60kph). Then the Zed lost good 1 car length in the 1st-to-2nd gear change (the small chirp did not help). It was already well behind, and lost another 1 - 2 car lengths by the time we shut down at 150kph. So I lost by good 5 car lengths.

test #2: 10 - 160kph, me in 2nd gear and HSV in 1st:
I thoght I'd try the same thing in 2nd gear just to get a better understanding of the HSV advantage. I justped on power a fractin before the HSV and pulled out about 1/3 of the car. Though, the HSV took only about 2 secs to be ahead of me and pulling away. It pulled about 3 car-lengths. by the end of 2nd and then proably another before 150kph. So the result did not look that different to the one above, but I did but myself at least one car length with my jump-start.

test #3: 40 - 150kph, starting in 1st gear both cars:
I figured let's start with a bit higher revs to try and reduce the HSV's low-revs-grunt advantage. We sarted from 40kph and things were a lot closer. Thins were pretty even while I was in 1st gear, but then lost good 1/2+ car length on the 1st-to-2nd gear-change. The HSV was slill in 1st gear then and pulled another car-length on me before 80kph (ie. before it shifted to 2nd). Then things stayed reasonably close and the HSV only pulled another carlength at most before we shot down at 150kph. So, again the win goes tothe HSV by 2.5 - 3 car-lengths.

test #4: 40 - 160kph, me in 2nd gear and HSV in 1st:
I thought I'd try the same run as beofre, but starting in 2nd gear. I thought that I would save one gear-change, but then would lose out at the start. To my surprise the HSV did not pull much before 75kph (ie. while the HSV was in 1st) ... it pulled only about 1 car-length and not having to do the 1st-to-2nd gear-change helped me while the HSV did need that change. After that things stayed very close and the HSV pulled only about 1/2 a car on me before we shut down at 160kph.

My observations are:
- At very low revs, the HSV has big advantage no matter what gear you're in.
- In 1st gear above 30kph, the HSV and Zed are pretty close.
- In 2nd gear (ie. 60 - 100kph) the HSV has an advantage. This was by far the most convincing segment for thethe HSV and there was nothing I could do in the Zed to keep up. Though, that might have a lot to do with the required gear-change in the Zed and the accumulated lost time from that.
- In 3rd gear I'd say that things looked pretty even for the Zed. The HSV stayed still in 2nd then.
- My guess is that above 100kph things should be about even, but bellow that the HSV has an advantage at the moment. Would have loved to done a run from 75 - 160kph as I think the Zed would have at least held it's own. Though this particular road did not permit such a test. Maybe next time.

I'll try similar 'test' once I got the hi-tech exhaust and then also once I got at least 7000km on my car. We'll see if things change.

ps. Just for reference, here's a similar 'test' I did against the same HSV R8 with the S2000 good 2 years ago:

test #1, run from 30km/h, both in 1st gear:
What happened here is the R8 pulled away straight away and even by the time I was doing 70km/h, it was already good 1-2 car lenghts ahead. By 140km/h (or 150) it was about 3-4 car lengths ahead. We run this 3-4 times and each time the S2000 just does not have enough go at 30km/h (about 4k revs) to keep up with the R8.

test #2, run from 70km/h R8 starts in 2nd and so does S2000:
Here the S2000 pulls away. It pulls away clearly up to about 105km/h (whole 2nd gear) ... I get about 2-3 car lenghts ahead. When I shift to 3rd the R8 starts closing in. By the time I'm doing 145km/h (end of the 3rd gear) the R8 is only 1 car lenght behind. Then in 4th (145+) it stays almost even ... S2000 is even pulling away a bit again. We run this test at least 5 times and had the same result every time.

test #3, run from 15km/h, both cars in 1st gear:
This is a total slaughter of the S2000. Because I'm doing only about 2k revs, I don't have much pick-up. The R8 on the other hand storms away to 6-7 car lenghts by the time I shift to 2nd and it's still pulling away. Even through the 2nd gear the R8 is so far ahead (not only on the road but with speed as well) that it is still pulling away. Tried this 2 times and had the same beating handed to me. You can't beat the R8's low-end power.

test #4, run from 45km/h, both in 1st:
S2000 is at around 6k revs when we floor it. Instantly I'm pulling away a bit (must be the comparatively low weight of the S2000 that allowed me to get the jump). It was very close but I did managed to be pulling away up to about 115km/h ... though, by then I was only about 3/4 of a car ahead. Then things looked even and probably having the R8 closing the gap slighlty up to about 145km/h. At the end of the run (145km/h) there was no more that 1/2 a car lenght between us (I was still ahead).

zuff

Both cars were never meant to be dragged (350z and s2k).

As you commented, both car kept up with the r8 from 45km/h. IN a race track application you'd never go slower than that and would eat the r8 around the corners.

ZZZ-35

David

Just the other day I was luckly to pit the Zed against a S2k, side by side at the lights. He jump me on the launch and got out to half a car's lenght but I managed to pulled him in once I got into 2nd gear and pulled half a car in 3rd before easing off, he pulled along side and asked "is it turboed", "no stock std" I replied, "pretty good" was his relpy. I think the HT system helped me out here plus over 15k on the motor makes a diff.

David

DavidM

Both cars were never meant to be dragged (350z and s2k).

hehe, true .... but that does stop stop me :-) I 'benchmark' most cars that I can against this R8 as it's good to know how things compare in the real world.

As you commented, both car kept up with the r8 from 45km/h.

I would say that the S2000 kept up from 45kph,but the 350Z did not ... it kept up from 100kph, but I 'think' that it would have kept up from 75kph as well as that would have forced the HSV to start in 2nd gear as well (and hopfully remove it's advantage).

In a race track application you'd never go slower than that and would eat the r8 around the corners.

Yep, spot on .... you rarely drop bellow 60kph and on a track. The S2000 had good 2sec advantage at places like Winton. Sandown is a different story ... those 2 long straights really do help car's like that and the gap is not as great.

I can't comment on the Zed's performance on the track just yet ... so for the moment I have to go by what the magazines say.

Just the other day I was luckly to pit the Zed against a S2k, side by side at the lights.

Good stuff, I want to line it up with an S2000 when I get a chance and so some detailed comparisions to see how they directly compare.

He jump me on the launch and got out to half a car's lenght but I managed to pulled him in once I got into 2nd gear and pulled half a car in 3rd before easing off

Did you guys both do an 'agressive' launch (ie. spin the wheels of the line)? Sounds like you went up to 130 - 140kph or so, correct? Looks like you had an advantage in 2nd and 3rd gear. I have a feeling that over 160kph the Zed should have had even better advantage.

I think the HT system helped me out here plus over 15k on the motor makes a diff.

Yeah, I would think so too ... and am hoping that is the case. I was thinking that as it is, the results for me were more or less as expected. With the exhaust and more Ks on the car the I should be able to shift the advantage towards the Zed (hopefully). I'll get to see what the exhaust alone does in week or so.

dixonbn

Agree with Zuff that if you want purely straight line speed the Z is not the first choice. In my former S15 I followed a HSV Monaro (GTO?) around the great ocean road for over an hour and he couldn't get away ... and the Z handles better than the S15 did.

zuffy

Hey, dixonbn...

How's that good looking car of yours going....?

Man, I wish I could put up with black. Still cleaning it every second day?

DavidM

Agree with Zuff that if you want purely straight line speed the Z is not the first choice

Hey, I want it all ... and with a big 3.5L engine the Zed is more suited to 'straightline speed' than most cars around.

dixonbn

Zuff, is ok but not cleaning every second day, but after a wash does only take two days to be showing the dirt again ...

BTW, finally got the centre caps for the wheels after a five month wait. When you saw the car it had the gaping big holes where the caps were meant to be.

KY350

DavidM, have you had an oversteer experience in the Z yet? I washed mine yesterday afternoon and had to take it for a spin. Turned off TC (Touring model) and induced a wonderfully controled oversteer slide around a left hand corner. I get the impression that the amount of oversteer is dictated by the speed you enter the corner (ie ridiculous speed = ridiculous oversteer). This is more fun than having the TC on and getting understeer as the first warning that you are going a bit too quick for the corner.

DavidM

Hey KY350, I have entered a fair few corners at pretty fast speeds, but what happens to me is that I get understeer when I enter the corner too fast (for the car). When that happens then I can't do much about it but wait for the car to wash off some speed and stop understeering. I have to enter the corners a tad slower than I'm used to (ie. 5 - 10kph less apex speed) and then I can control the car a little bit more with power. Still, no wild slides or anything, just a minor drift from the back. I'm running 33/37psi (front/back) now and the car seems better ... but I'm not sure yet if it's the pressures or just the hot weather (ie. grippy tarmac) we're having at the moment. Either way, I'll try and 'dial' more front-end grip into my car as soon as I'm confident in how to do that.

Also I had the reat step out a little bit (ie. 3 - 4") around this slightly off camber round-about ... it was on the left-to-right transition, but again, nothing wild just very mild and gentle.

Oh, mostly I'm experimenting through 2nd gear corners (ie. 60 - 80kph) so most of what I say applies to that. I have not tried it around 1st gear corners (if there is sunch thing in the Zed). Over 100kph I don't really want to be sliding too much on roads that don't have much run-off :-)

Turned off TC (Touring model) and induced a wonderfully controled oversteer slide around a left hand corner.

What gear/speed was that (roughly)?

This is more fun than having the TC on and getting understeer as the first warning that you are going a bit too quick for the corner.

I can't drive with the TC/VDC as it kicking in way too much for me. I switch it off 90% of the time (ie. anytime I think I'd like to 'enjoy' the drive and it's dry). I can even get the TC to kick in on gear-changes here and there (ie. really fast 1st-to-2nd gear-change) and VDC does not take much cornering forces for it to kick in as well. So I find the car so much better without it.

Not sure why the TC/VDC is there concidering that the car is dialied in so much safty (ie. tons of rear grip and a fair bit less front grip). Seems a bit redundant to me in this car .... in the HSV R8, it's a different story though :-)

DavidM

Take #2, as I raced the HSV R8 again. Though, now I have the Hi-tech exhaust (and K&N filter) fitted. I have another 300km or so on the car as well, but I don't think those Ks amount to much of the gains.

Without needeing to re-read the 1st results (ie. in the 1st post here), here's a quick summary: The HSV was certainly and noticeably quicker as it'd get 2 cars on me before 100kph (most of it lost in 2nd gear) and then another 2 by the time we hit 140 - 150kph. There was no speed/gear I could start in that would make me hang with the R8 and it was in the 3rd gear when I would say I was holding the R8 the most (ie. the best).

This time the races looked much better (from my point of view) and here are the results:

test #1: 40 - 150kph, starting in 1st gear both cars:
The two car's stay dead even until I have to make the 1st-to-2nd gear-change (around 60kph), where I loose about 1/2 a car-length. Then the two car's stay dead-even again (ie. no one pulls) 'till around 100kph where I have to make the 2nd-to-3rd gear-change. Here I loose another 1/2 a car-length and the HSV is still in 2nd gear so it pulls away another 1/2 a car-length before it shifts to 3rd at around 135kph. After that things look pretty even to 150kph when we shut down. So the HSV won this one by around 1.5 car-lengths. The HSV has stil lan advantage over my Zed in the 100 - 130kph range as it is still in 2nd gear while I have to be in 3rd. Though, the advantage is very small now.

test #2: 50 - 150kph, me in 2nd gear and HSV in 1st:
The first run we did the HSV got a jump on me and therefore it looked like it was steadily, but slowly pulling away all the way to 150kph, by which stage it was around 3 car-lengths ahead. When we run the 2nd time, we took off more evenly, but the HSV was still quicker than me ... but not by much. It pulled away maybe 3/4 car-length on me by the time I shifted to 3rd (ie. 100kph), where I lost maybe 1/4 car as well. It stayed like this all the way to around 150kph where we shut down and I was not pulling the HSV in, nor was it pulling away. I lost this one by 1 car-length.

test #3: 20 - 165kph, me in 1st gear and HSV in Drive:
As soon as we floor it, the HSV has to down-change (to 1st gear) and I get about 1/2 a car jump on it during this time. I hold this all the way through 1st and don't really loose any ground on the 1st-to-2nd gear-change ... only about a foot or two. Then I pull away another 1/4 to 1/3 car-length before I need to shift to 3rd (ie. 100kph). So the HSV is on my rear-quarter panel and I shift to 3rd, loose very little ground and then we run all the way to 165kph by which time I maybe pulled another 1/2 a car-length. That means that at the end I was around 1 - 1.5 car-length ahead and there was no pulling away or gaining from either of us.

I'd say that now the 350Z is about line-ball in terms of acceleration with the HSV. The 350Z looses a little bit of ground on gear-changes (even if you nail them really well), but it is no longer slower in-gear. In some ways it can even pull away fraction in some increments, but I'd call this pretty damn even as I'm sure I can out-launch it by 1 - 1.5 car-lengths (mostly due to the weight).

When comparing this to the 350Z with the standard exhaust, I'd say than in the rolling starts I'm good 4 car-lengths ahead by the time I reach 150kph ... that is around 0.3 - 0.4sec in a 400m run, so I'm pretty impressed. Oh, and I'm no longer slower through the 1st and 2nd (in particular) gears than the HSV.

I'd say that I'm at least as quick as an S2000 in full-flight now, and a lot quicker in low to mid revs. Incredible that 'just an exhaust' can provide this kind of gains. Or even more incredible that Nissan would fit the car with an exhaust that 'strangles' the engine so much?!

ZZZ-35

Nice gains, I'd like to see the comparison when you get around another 10K's on the clock.

David

DavidM

Nice gains, I'd like to see the comparison when you get around another 10K's on the clock.

Yeah, I agree ... I'm guessing there should be another 2 or so car-lengths coming my way with some more milage.

KY350

Hi David

The left hander is a 90 degree corner that I appoached going uphill. On approach, downshifted from 3rd to second and I'm guessing that the revs would have been 3.5K +/- 500. I'm not sure what speed that is but again, I'm guessing about 45-50km/h. As I was driving up a hill before the turn, the street I turned left into would have a natural camber that assists the cars turn to the left. Even with this assistance, the back end ultimately broke out into oversteer, helped by my eager right foot. BTW, I check my pressures and they are currently 35psi all around.

Also, TC results in slightly subdued acceleration in the dry, but is great in the wet. Even normal stop light acceleration in the wet without TC yields easy wheelspin, which is frustrating.

The next 2 weeks will be slow motoring for me with Double Demerit points over the holiday season - damn!

Finally, did you stage your comparison with the R8 going uphill / downhill / or level ground? From my experience, racing uphill against a V8 is an advantage to the 8 due to better torque. But racing downhill benefits the lighter car somewhat.

Next time you and your dad are out having fun, try a race from standstill. I am interested to see if the Z with HT can keep pace with the R8 to 100km/h and over the quarter mile (approx 160-165km/h). A 1 and 1/2 car length advantage over the R8 on launch would be very impressive.

DavidM

Thanks for the info KY350. I'm still getting understeer when pushing hard. Even if I got the car hooked up at the apex as when I start feeding more power then the front starts pushing.

BTW, I check my pressures and they are currently 35psi all around

I was running 36/36 for about 4 weeks and now (for about 2 weeks) I've been running 33/37psi. So far I prefer the 33/37 setup. I'll probably trya few other settings before I settle on something.

Finally, did you stage your comparison with the R8 going uphill / downhill / or level ground? From my experience, racing uphill against a V8 is an advantage to the 8 due to better torque. But racing downhill benefits the lighter car somewhat.

In both directions and on flat ground. Though, you're probably right about the uphill bit.

Next time you and your dad are out having fun, try a race from standstill. I am interested to see if the Z with HT can keep pace with the R8 to 100km/h and over the quarter mile (approx 160-165km/h). A 1 and 1/2 car length advantage over the R8 on launch would be very impressive.

I'll see what I can do when I get the change. Though, I'm sure that I can out-launch the HSV as I did some 'comparisions' between this HSV and the WRX that I mentioned in the other thread. I could not beat the WRX off the line in the HSV and at best could shadow it (ie. loose a foot during the launch). Once on the move the HSV was always quicker than the WRX. Anyway, going by that, and that I could get 1 - 1.5 car-lengths on this WRX with the 350Z, I'd say that I could get the same gap during the launch on the HSV.

Besides that, we went to 165kph in one of the runs mentioned above and there was not much (if any) difference between the Zed and HSV. I'm guessing that it would stay like that to 180kph and after that the HSV would be quicker as it stays in the same gear while the Zed needs to shift to 5th.

I would love to put it put it to the test but there's not many places suited to that kind of a 'test'. I do know some though, so maybe one day ;-)

A-Bomb

i would be willing to bring out the family car, in the name of testing

DavidM

i would be willing to bring out the family car, in the name of testing

Is there anything 'special' about the family Commodre? I see that you have a different cover on the engine block, but that is all I can tell from picture. Also is it auto or manual?

ps. just by the color of the number plate it looks like you're not from Melbourne ... is that correct?

pps. My mum has a new Monaro CV8-R (ie. the limited edition). Very nice car, but I don't think it's anywhere as quick as the HSV ...though, that's something I should put to the 'test' ;-)

lionking

Had a drag with an SS Commodore today. I have no idea what an SS Commodore is (year model, power, etc) but that's what the badge said and it looked pretty new. Oh yea, and it was green. Maybe they should make a green 350z - NOT! Was one of those " are we gonna???" moments as we pulled from the lights. Both powered on about 15-20 kph. My rev's were down but we stayed absolutely even side by side to about 100. Shut down after that. I haven't got many points left. Still got 12 months before I get most of them back. I recon you should be able to get free bonus points when you buy a Z!

DavidM

Had a drag with an SS Commodore today. I have no idea what an SS Commodore is (year model, power, etc) but that's what the badge said and it looked pretty new.

Sounds like the new SS. It has the 5.7L V8 GenIII engine that is in all V8 Commoderes since 1999. The SS weights around 1650kg and in the current tune has 235kW power and 440Nm of torque. They started with 220kW 4 years ago, and every year get extra 5kW or so. Anyway, it's the same engine as in the HSVs, but in the Commodore is is a lot weaker, even though specs don't indicate so. In a HSV there is abbundance of power from idle, while the in a Commodore there seems less power down low than in my Zed and it only really starts moving when it has around 4000rpm on the tacho.

Still, that does not mean that they are not quick. They have clocked them localy as quick as 5.9sec to 100kph and 13.9sec for 400m. Though, usually they return low-mid 6s and low-mid 14s respecively. In other workds plenty quick enough. With an Auto box the Commodores suffer a tad down low, but are not that much slower than the manuals (ie. less then 1/2 a sec in both increments) .... and are probably quicker in most driver's hands. On the other hand, the HSV auto is barelly slower than a manual due to it's large low-down advantage ... I think it's actually quicker over 400m as it's geared better for that.

Both powered on about 15-20 kph. My rev's were down but we stayed absolutely even side by side to about 100.

Thanks for the story .... sounds like you guys floored it only for about 4secs of so, but I'm not surprised that it stayed with you .... they have a lot of straight-line grunt.

lionking

Thanks David. You are like a human information machine!!! Yesterday, to me, it was just a car with a couple of s's. Now I'm a little more educated. Is great to get this sort of information feedback.

Would be interesting to drag the auto Z against the manual Z. The auto Z goes fairly well off the line and has instantaneous gear changes with manual shifting. First gear limits at 60 and I think 2nd will go past 100 (although I've never really looked at the speedo for a precise reading - usually wathcin' the rev's). I'm pretty sure David could tell me exactly ... David, maybe you could give your theories on this match-up?? Or even better, maybe we can test this one day?? Although you would have the advantage with the Hi-tech.

Slowly learnin' about cars,
LK