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Discussion Starter #1
That's what the NISMO guy at the TO Infi meet told me yesterday. Essentially, without FI or an ECU chip, there's not a lot more that can be done to the 4.5L . One thing I did find out that was interesting was the NISMO guys won't touch the Infiniti-only-branded stuff 'cause of internal politics.

Nah, I don't get it either.
 

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I have found a remarkable lack of communication between Inf and Nissan.I am planning on installing the LSD on my FX45 and while I now have part # match only 2 souces say it will work..Inf says no(yes you have to keep rear ratio the same as the 45. ..that's easy)..

Never met a car that did not benefit from breathing and exhaust enhancements and mine cetainly has.Thought I would add more,a modified trans for faster firmer shifts should yield half a car lenght on each shift racing beside a stock trans(and probably extend trans life-less slip,less heat).A looser torgue coverter could be a tenth to 5 tenths(we're guessing 5 tenths on the FX45 but more heat)Nothing radical here,just time proven mods away from the ECU and yes I would love to have that 35hp in the Q as a higher starting base
 

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Which LSD do you plan on installing on your FX? The one from the Q?

Just wondering. It is kind of sad that there are no mods out for the FX45. You guys are our only chances to getting above and beyond the Porsche Cayenne Turbo levels! :p

I wonder how a twin turbo set up in the VK45 would match up against the twin turbo of the Porsche considering the weight difference.

lol...
 

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The one that Nismo handles (350Z/G35) all same parts #.We only need 50 hp to cover a Cayanne turbo so you do not have to go crazy(weight diff).The ECU could get you 20-25 of that.The transmission stuff is not HP,it just makes you quicker and in a race it all equals the same.
I just got off the phone with Procharger and they have only sold 1 FX35 kit,so no plans for the 45,BUT,one of their installers are friends of mine(Buick) in Baltimore and they will share info,cooling system and fuel enrichment, that if it works,I am only looking at brackets and tubing.But as crazy as I get on this stuff,,I still pay a little attention to cost and if I can get the HP cheaper why get 100+.

As I have said before,I know where I have to take this car.I would hope not to have to fabricate everthing.The 35 was never an option(no offense),I did not expect the 45 to be this difficult

Is the Q-LSD mechanical or electronic through the brakes?
 

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If you put in the LSD, have you figured out how to defeat the electronic brake LSD that is in effect under 20mph?
 

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The electronic LSD feels slow and the mechanical has 3 settings and I would opt for the mid or highest(tightest) setting(adjustable without pulling it back out).Therefore the mechanical would be acting before the electronic would pick up the slippage...in theory!
 

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Just got a call back from Nissan Motorsport and the Nismo LSD for the 350Z will fit the FX35 and 45 YEA!!

Theyare available at about$1000 plus install
 

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Could you please explain in layman's terms exactly what you're talking about here? Is the "LSD" you're speaking of the limited slip differential? What is the potential gain is switching this unit?

Thanks,
Don
 

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Discussion Starter #9
FromHereToInfiniti said:
What is the potential gain is switching this unit [to a limited-slip differential]?
What I wanna know is how will ATTESA-ETS respond to this mod? Will it bolt on seamlessly, or will we lose some AWD compatibility?
 

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Some very different questions:
-All 4 wheel or all wheel drives are really 2 wheel drives...one front and one rear without a locked or limited slip diff at one or both ends.Our system controls one wheel spinning by applying the brake on that wheel and typically causes the other to drive...you are not directing or sending power/torque or forcing the non-spinning wheel to take load...you are simply stopping the spinning wheel(the computer does all this and will even SEND torque to the other axle in increasing amounts).With a mechanical LSD you will SEND torque to the other wheel and the computer may also SEND torque to the other axle ,limiting slippage should occur so fast as to control it before the electronic system acts and applies that brake..it is slow.
In drag racing or autocrossing you want more than control of the spinning wheel and you truly do not want the application of the brake(slows you),you want both wheels drining especially in corners or on the track..Therefore the LSD will SEND power to both wheels in launching the car and in cornering. Because there are 3 settings,you can set this up tight for the strip and autocrossing to max handling and launch...excess slippage will bring the computer in and it will apply a brake
If you are not racing,autocrossing or driving really hard,this is a lot of $..(or have really bad winters)
It is on the 350Z for handling and launch(starting)
On the negative LSD's have a tendency to cause walk sideways when both wheels are slipping,but our attitude control should control that
I hope I have made that clear/er.
 

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The NISMO LSD diff will be here in a couple of days...everyone confirmed the fit.Talked to the top mechanic at dealersip and he would do it but they usually just get a whole pumkin and replace as I stated earlier...so contacted some racer friends with a shop and they simply asked that the dealer remove pumkin and they will do the diff swap..they have done hundreds and I feel more comfortable with someone with confidence and all the toolsVS someone who may do one every few years..Setting up trip to Level 10 for more trans work and converter and waiting on the CAI...All the spring projects coming together...then off to the track one cool evening..Atco often has below sea level air density on cool nights(more O)
 

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Continuing the update:Nismo LSD paid and shipped(waiting).Transmission second mods ,and higher stall converter scheduled for 6/15(want car for 3 days).CAI still waiting on Paddock as are many of you.On phone with a contact at Random Tech for high flow cats(will not be bolt on but clamp or weld on) Looking for a header manufacturer who wants a low volume challenge???Slower timetable than I wanted but will be done in June it seems
 

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Today the dealership said that they would not pull the pumkin for my shop to install the diff..afraid of problems/lawsuits etc/BS...my guy will do it Wed/thurs.Parts are here
 

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Cool. Keep the updates coming. I'd really like to do this myself. Can you post pics of the Nismo parts? How much did you get it for?
 

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$900 fromPerformance Nissan Parts(38420-RS141) (Jason).Pictures on their site and Nismo site(Z33-LSD),this is the 350Z unit.

Paddock had said they broke the tube bender for mandral bends,they needed a tighter bend than the earlier model because they needed a larger filter(I was adament about the larger filter from past experience)
I had wanted the trans redo and torque converter to be last because it will max the other mods and should yield at least 0.5 seconds in quarter,.but Murphy!If I can get the Cats before the 15,I'll ask Level 10 to weld them in
 

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NO it does not fit!The diff appears to be the same,the splines are the same,But the collar which holds the axles in the diff are larger on the FX than in the kit.Solvable ,yes,but not by me, Nismo will take it back.He said this was the one area of uncertainty..oh well!
 

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Crap. So does this mean it's out for the RWD '35 as well? I don't get it, comparing the manuals for the FX and G35, the diffs are the same (same model, same gearing...). Not sure about the '45, but I thought they used the same rear diff.

Hmm, looking at Infiniti-parts.com, though, the diffs are different prices for the G and FX, so that may be an indicator (wish they listed part numbers).

Any possibilitied from other aftermarket suppliers?
 

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brnjugfx45 said:
NO it does not fit!The diff appears to be the same,the splines are the same,But the collar which holds the axles in the diff are larger on the FX than in the kit.Solvable ,yes,but not by me, Nismo will take it back.He said this was the one area of uncertainty..oh well!
When we were replacing my exhaust, my brother commented on how "beefy" the rear axles and u-joints were. He says they should be able to handle all kinds of power :twisted:. This is sort of predictable if you consider that the tires must a) rotate slower because they are larger circumference (which means higher torque load), b) designed for "quasi-offroad" use, and c) must handle a V8 engine in addition to the V6.

I'm not sure about a). Our tires are definitely bigger, but maybe the G35s just cruise at a slightly higher RPM than us. Is the final drive ratio the same for both cars? 350z too?
 

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I have a friend looking at the electric LSD that is on the market to see if they are interested (US stuff).

I would guess it is a simple(if you had a machine shop) fix...machine a collar to fit the nismo diff.If Nismo is serious about being here,this should not be a difficult addition.Jason(my contact) was willing to explore it,lets see if others will listen

The axles are beefy for reasons of AWD or weight ,I do not know

ratio is diff for 3.5 vs 4.5
 
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