Adam@Z1auto.com

the ecu does not cancel out such mods - however, every car can, and often will react differently to similar mods. Some setups provide more gains than others, and some cars will show more gains than others when outfitted with the same mods.

Is there a point of diminishing returns? Absolutely- and this is where a proper ecu retune can really shine

The same software is used on all the ecu's from Japan to the US and worldwide. There may be minor differences in timing and fuel maps based on different fuels, and I also believe the immobilizer features differ slightly from country to country

group buy? can easily supply these! I'll get the details posted shortly

hey guys Thanks Stew for the PM

Fitting a lightweight crank pulley is akin to fitting a lightweight flywheel - similar change, but on the other side of the crank.

The pullies are offered for all 2002 (I think that's the first year of the Z in Japan, in the US it's 2003) to 2008 Z's. The 2002-2006 cars all use the same exact ones. The HR engine (2007 +, the engine with the dual intakes) uses a totally different pulley.

Basically they work by reducing rotational mass. Give me a little while and I'll post the weights on both options. The net change is due to the reduced weight. Overall the engine revs noticeably quicker with the UR pulley installed vs stock. Some people have reported horsepower gains as well, others have not realized these. I'd suspect this is down to the anomolies of one engine vs another - they are like fingerprints at the end of the day.

As far as underdriven vs stock diameter, it really doesn't matter unless it's a very, very high revving engine. The underdriving lets the accessories spin at a slower speed, which reduces parasitic drag. Same type of theory as using, say, an electric water pump vs a chain or timing belt driven one. The less things you're asking the crank to spin, the less energy is being lost. Overall on a Z though, the differences between underdriven vs non are basically nill, as most people are not running high enough rpm's to notice the difference. Most of our customers go for the stock diameter unit.

As far as the full pulley sets vs the crank alone, as mentioned, the net change is mostly a result of the weight reduction. The factory accessory pullies for the water pump and alternator don't really weigh much. So, the crank pulley alone is the one that effectuates the change. The accessory pullies essentially just look pretty. So for those who want some more underhood "bling", the full pulley set is a nice option and really looks great on the car.

I've seen the Brazil one from last season before.

 

They are superbly edited. They really capture the atmosphere that F1 is much more than a race.

 

And there is not a FIA hearing to be seen! Result!

lol - seriously! in the big business world that is F1, they seem to wallow acting like the polit-bureau, making mountains out of mole-hills. But I suppose when you've got a small room with lots of wealthy people all fighting to be #1, some level of iron-fistedness is needed

what year is the car? what are your primary uses? what tires are you running? have you owned a fully adjustable suspension in the past?

fwiw - Eibach coilovers are KW's. They work well on the softer settings. They are less than ideal on the stiffer settings, as they become out of shape quite easily (in other words, rebound rate doesn't match the compression). All relative to your budget, and uses though. V3's are much better, but take considerable time to really set up well, as they are independant adjustments for compression and rebound.

I'm sure alot of you guys are familiar with these, but figured not all have seen them. As much fun as the races are (I absolutely LOVE F1, I am a diehard addict!) one of the things I look forward to most are the videos that are posted on formula1.com after the race. The editing is absolutely fantastic and the footage is not just the typical world feed stuff recycled. It really is enjoyable to watch....the music is usually excellent as well!

http://www.formula1.com/services/play_video.html

Anyone else a fan of how they put these mini-movies together?

can easily supply them

free bump for a good seller

IIRC and what Adam is elluding to is that its only the "base" models that dont have LSDs. Anything more than base will have one

I just didn't want to come out and say that because I don't know if the trim levels are all called the same thing worldwide, or if some countried get features others don't with certain trims

Thanks for the informative post Adam. I'm amazed that you only saw a 2BHP difference from one dyno to the other, I've seen more variation than that between 2 DynoDynamics dynos before.

 

My own car went from a baseline of 225 whp to 257 ish without a tune, to 269 after a tune.

What mods were used to achieve this? My car made 240WHP on a DynoDynamics, but I have a feeling that the popcharger negated any gains I got from my plenum spacer (intake temps were quite high, much higher than ambient). Also how did these mods effect the torque curve? I seem to remember that a member on here (maybe Ian) fitted decats (testpipes) and although it netted him some top end power, he lost quite a lot torque low down. I guess a remap might sort that bit out though.

My mods at the time:

Gruppe-M intake

Unorthodox Racing crank pulley

Ultimate Racing ceramic high flow cats

Ultimate Racing Y pipe

Apexi World Sport 2 exhaust

I then had a reflash done to my ecu in fall 2003. Drove the car that way till Turbo XS got me a beta tester UTEC in December 2005. I'd have to try to find the dyno sheet from when I got the reflash done - the gains were noticeable though, about 8-10 whp and about the same in torque if I recall. The reflash was done on my car, not as a mailorder thing (I personally don't like those but that's just me)

By the time I was tuned on the UTEC, the only part I had changed was the exhaust, to a Fujitsubo Titanium - everything else remained the same.

this is my dyno sheet from my pre UTEC tune (running reflashed ecu) compared to post UTEC tune - the gains were noticeable, and substantial

http://www.z1auto.com/images/scan.pdf

How do you guys know he has an LSD? I just read one of the other sites that not all Zeds have it.

 

Not sure what spec my JDM is but it has brembos, VDC but no leather/satnav etc. Would I have a LSD?

 

Sorry to revive an old topic

because all Z's with brembo's have LSD

All Z's with VDC also have LSD's

Let's hopefully dispell some myths

First, there are several bolt ons that will make power - it all depends on what specific items we're talking about, and what year the car is. Test pipes, high flow cats, spacers, many exhausts, all will net some decent gains on most cars. My own car went from a baseline of 225 whp to 257 ish without a tune, to 269 after a tune.

Doing a series of runs before hand, and a series of runs afterwards, logging things like TPS (throttle position), Injector Duty Cycle (IDC) and Timing, and using a wideband 02 sensor. With that data, you can then see exactly what the car is seeing, and see exactly how the ecu is reacting to the changes that have been made. Of course, every car is like a fingerprint, so it's not unusual for 2 cars to have different reactions to the same modifications..but they will generally fall into the same categories.

It's also important to either use the same dyno each time, or, to ask the dyno operator what cars similarly prepped put down. This will at least give you a general idea of where you fall relative to where it should be. Switching between dyno's can create annomolies that confuse things. For example, when I first built my engine back in 2007, I spent about 900 miles breaking it in per my engine builders suggestions. I then brought the car to my tuner, a friend of mine at a shop in Connecticut (as I don't own a dyno). After he mapped it (UTEC) we netted a final result of 302 whp. This was on a Dyno Dynamics. I then drove the car for over a year and a half, and over 10k miles. Last fall, I took a weekend trip down to Maryland to see a friend of mine, who happens to work at Turbo XS. We put the car on his dyno (Dynapack) and low and behold, it put down 303.9 whp. I had made zero changes to the hardware or software of my car from the original July 2007 tune till the one in Fall 2008. From there, we did some changes to the map, and found another 16.5 whp - culiminating in a final # of 320whp. Keep one thing in mind guys, the # is really quite arbitrary IMHO. The net change in not only the #'s, but the shape of the curve, is what you're interested in.

I am personally not a fan of the popcharger, but many use it because of it's low cost, and sound - nothing wrong with that at all. Just realize that you will likely net the same power figure with a stock airbox. This is especially true for 2006 cars which have a slightly revised airbox from the factory vs 2003-2005 models (the 2006 ones have a nice venturi built in).

Don't always rely on the "butt dyno" - sometimes we perceive gains where there are none, and vice versa.

Be aware that any engine mods you do will not improve performance as the stock ECU cancels any gains out.

to be honest, nothing could be further from the truth

there ARE gains to be had from bolt ons, if properly selected, and even more gains to be had with proper engine management tuning

out of all the parts that can be changed on this car, the air filter is the least important. Aftermarket ones will provide better (subjective) sound, and cold air intakes will provide more consistent air inlet temperatures at speed (and recover quicker when the car is left idling)

Hi all just a quick update - pedals should be arriving with us in the next few days, then we'll ship them out to Tim

I already have a apexi safc in the car. Would this kind of be the same thing for the 350.

Gets you half way there from what I understand. It makes the AFR correct (or as close as possible) but thats where it stops. Piggyback ECUs allow you access to other things such as timing advance which get you more power. So short answer is it does some of it

Based on how the SAFC works it (unfortunately) also alters timing maps as well. Problem is, you have zero control over it (as you lean the car out, timing advances, as you richen it up, timing retards). Biggest issue is that since it has no drivers and is just manipulating maf voltage, you only have a very very small window for changes. Based on other alternatives out there, I'm personally not a fan. Especially considering that once you add in the various widgets to truly make it compete with the plug and play options, it really doesn't end up much less expensive either

can't even buy them in the US anymore, NISMO USA discontinued them now. I found a set for a customer about 2 weeks ago after scouring through the inventory report from NISMO. Found 1 dealer than had it, and managed to grab them (at full retail)

no engine on the planet wants backpressure..NA, turbo, or supercharged - backpressure is bad in all cases

many people confuse backpressure and exhaust velocity. Do some searches online, there is a wealth of info up there

As been said lots of cheap replicas available so be careful.

 

I fitted one (replica) to a mates Z last week and as Adam said I had to modify the diff housing.

 

No mod required to the diff housing on the JDM.

 

Alex.

Alex - the JDM ones I guess use the same housing as US (unfinned?) good to know

you will not lose power with any high flow cat or test pipe

UK cars require modifications to the diff housing to fit this exhaust

saw the car in the flesh yesterday at the NY Int'l Auto Show - it is absolutely stunning. The car is very well proportioned, has a fantastic stance (visibly lower than a standard 370), very nicely appointed interior (NISMO badging on the seats is a nice touch). The direct injection should prove interesting on the tuning side of things. The wheels are much nicer in person than they are in pictures. I still wouldn't keep them (LM-R's please!) but they do look very nice. Tires are 255 up front, 285 out back if memory serves. The headlights are much cleaner looking with the new front fascia. The rear bumper, with it's GT3 esque vents, is a looker. The rear spoiler as well is very reminiscent of the 2010 GT3 as well (which to me, was the hottest car there, tied only with the SL65 Black). The brakes are the same Akebono's used on the G37...BIG rotors, so certainly looks the part. The aftermarket will catch up in the coming months with pads

more arriving in about 10 days

http://www.z1auto.com/prodmore.asp?mode ... rodid=2976

we also offer lower pressure units for those with carbon hatches

http://www.z1auto.com/prodmore.asp?mode ... rodid=3412

we have supplied these to members here before

over 4000 feet was the highest I went in mine so far - car ran like poo lolol

the run down was epic though

looks great and good luck with her! It's a helluva machine!

fuel pressure would not be the issue

if one half of the engine is running fine and the other is not, as evidenced by the 02 sensors, then one of the 02 sensors is likely faulty. Best remedy is to replace both