Bnr34 V-spec Handling Upgrade...

[Ares180BPM]

Hey all,

Have an R34 V-Spec that's going in for some minor surgery shortly, just wanted thoughts and opinions.

Engine is running around 400bhp (a little over 300kw) on a dynapack at 15psi

Just shy of 160,000km (almost 100,000 miles)

Background Mods:

Midori Spec G-Sensor

Stock Diffs

Exedy Heavy Duty single clutch

BBS LM 18 x10

Falken FK453 Tyres - 265/35/18x10

Factory Brembo calipers

Spoon rigid collars

Current:

Factory Discs (Need replacing)

??? Pads (were told they were Endless, but unsure)

Tein CS (Comfort Sport) adjustable coilovers

Proposed new setup:

DBA 4000 series Slotted rotors (T3 front, T2 rear)

Endless MX72 pads front and rear

Ohlins Road and Track adjustable coilovers

Nismo engine and gearbox mounts

Car is used mainly on the road; highway cruising and Togue with occasional track use.

Would love to shell out for a full brake upgrade but not in the budget presently.

Will get bushes inspected when it all goes in and replace or upgrade any that need it.

Wondering about a brake stopper brace as well...

Any thoughts would be greatly appreciated!

Edited February 3, 2015 by Ares180BPM

[GTSBoy]

List seems fine. Seems to miss out on a number of near essential things like adjustable caster rods, bigger ARBs, etc. Nismo rear diff and helical front diff are a massive upgrade (but pricey in the same way that big brakes are).

[djr81]

List is a bit random.

You have, for example, an expensive brake pad with a cheap rotor.

I would, randomly, recommend:

A 2 piece front rotor, Dixcel or Project Mu.

A pad of similar capability to the Ferodo DS2500 for the front and a similar friction coefficient for the rear but not a DS2500 at the rear as it promotes rotor wear when cold.

Get some neg camber for the front suspension.

Get some anti roll bars.

Standard mounts are fine at that hp but Nismo is ok too if you are replacing them.

Ohlins are expensive for what you get.

"Solid" suspension just about anything is a wank and an annoyance on a road car. They just make the car go clunk and not much else.

[Piggaz]

A real front diff. Best handling mod you can do to these things. V spec or not.

[StretchGSK]

Interested to see the Spoon rigid collars installed

Any chance you have a before and after opinion on this mod?

As much as I want a set of Ohlins I have to agree with djr81in that you can achieve the same result with something a fair bit cheaper.

Check out http://mcasuspension.com

Interesting comment Piggaz... what would you call a real front diff and can i bug you for a 2 line reply on what the benefits would be?

[GTSBoy]

I already pointed you at a helical front diff, of which the star of the show, the Quaife, is the leading example. There is a massive thread on the 2nd page of the Drivetrain forum.

[Ares180BPM]

Will look into the differentials but the money isn't there at the moment.

Spoon collars have been in a while now they definitely changed how the car feels, adding rigidity and aiding alignment - both great improvements - however the biggest advantage of them was the increase of feedback through the wheel and car asa whole, on road conditions etc.

A friend who'd driven the car previously made the comment that it felt dead, that the car was in control and he was just there suggesting where it would go.
After the collars he found it to be not only more alive, but that he had a greater feel for what it was doing.

It's hard to explain but it's definitely made an improvement.

Regarding my random list (hehe)
I've run DBA before and as a compromise between street and track found them to be excellent. This car may turn into a daily at some point, so i'm needing to think about longevity too |
Will consider Ferodo for next set - had the MX72's recommended by my mechanic/guru who really knows gt-r's

Can you suggest camber arms and roll bars? Car has a lot of bracing from factory and haven't found rigidity a problem but could look at it
At close to 160,000k i'm guessing the mounts are close to flogged, so nismo mounts seem like the go here - especially given the price of standard!

Car has 'difficult' suspension at the moment - can't seem to get the balance right - it seems to bounce a lot, yet the rear diffuser will bottom out when driving on normal 100km b roads here in NZ

I figure I want to spend my money on the good stuff handling wise to try to mitigate some of this.
My last ran bilstein shocks with tein springs - non adjustable - firm but good setup and a good balance between road and track driving, which i'm hoping to achieve again here.

Thanks for the input guys - muchly appreciated!

[KiwiRS4T]

Cusco camber arms for the front. Quality costs but safety an issue with cheap brands.

[djr81]

Will look into the differentials but the money isn't there at the moment.

Spoon collars have been in a while now they definitely changed how the car feels, adding rigidity and aiding alignment - both great improvements - however the biggest advantage of them was the increase of feedback through the wheel and car asa whole, on road conditions etc.

A friend who'd driven the car previously made the comment that it felt dead, that the car was in control and he was just there suggesting where it would go.

After the collars he found it to be not only more alive, but that he had a greater feel for what it was doing.

It's hard to explain but it's definitely made an improvement.

Regarding my random list (hehe)

I've run DBA before and as a compromise between street and track found them to be excellent. This car may turn into a daily at some point, so i'm needing to think about longevity too |

Will consider Ferodo for next set - had the MX72's recommended by my mechanic/guru who really knows gt-r's

Can you suggest camber arms and roll bars? Car has a lot of bracing from factory and haven't found rigidity a problem but could look at it

At close to 160,000k i'm guessing the mounts are close to flogged, so nismo mounts seem like the go here - especially given the price of standard!

Car has 'difficult' suspension at the moment - can't seem to get the balance right - it seems to bounce a lot, yet the rear diffuser will bottom out when driving on normal 100km b roads here in NZ

I figure I want to spend my money on the good stuff handling wise to try to mitigate some of this.

My last ran bilstein shocks with tein springs - non adjustable - firm but good setup and a good balance between road and track driving, which i'm hoping to achieve again here.

Thanks for the input guys - muchly appreciated!

If it is bouncing a lot then the shocks are not controlling the body motion. If it is bottoming the chance are you have too much low.

If you had Bilstein before then why not get more of the same. Find yourself a spring rate you are happy with for front & rear, check with Bilstein that its in the range of the shock, buy the bits you need to put 10" Eibach 65mm springs on the dampers and that is done.

Sway bars need to match the spring rates. Problem being they all quote different numbers. But look at Nismo if they are available at reasonable dollars. Also Cusco but they tend to be well hard.

I hate rose joints and bracing as most of the stuff sold is useless. There is nothing wrong and a lot right with decent bushes.

Don't guess that stuff is flogged. Get it up on a hoist and look.

[Piggaz]

Interested to see the Spoon rigid collars installed

Any chance you have a before and after opinion on this mod?

As much as I want a set of Ohlins I have to agree with djr81in that you can achieve the same result with something a fair bit cheaper.

Check out http://mcasuspension.com

Interesting comment Piggaz... what would you call a real front diff and can i bug you for a 2 line reply on what the benefits would be?

http://www.sau.com.au/forums/topic/422006-front-cusco-lsd-on-gtr/

Have a read.

In all seriousness, if I had my time over again diffs would be in the group of first mods I would do to a stock car. The stock stuff, especially the front is trash.

[StretchGSK]

I did many 1000's of KM on the B roads around the North Island on a set of Bilstein PSS9 coilers and never had any issues bottoming out.

They are a little bouncy on the soft setting but otherwise very well controlled.

Thanks for the link Piggaz, Ill have a read later tonight

[Ares180BPM]

Hey all

Bit the bullet and have a quaife on the way.

Super glad I got the engine mounts done!

An intercooler pipe was misaligned which has now been corrected - Holy Overbooost!

Been driving very carefully and a retune isn't far off.

Edited July 21, 2015 by Ares180BPM

[R31Nismoid]

You'll love good diffs.

Make sure you do the rear as well though.

http://www.sau.com.au/forums/topic/422006-front-cusco-lsd-on-gtr/
Have a read.
In all seriousness, if I had my time over again diffs would be in the group of first mods I would do to a stock car. The stock stuff, especially the front is trash.

haha you sound exactly like me now.

+1 though. If I had another GT-R, I would change our the ceramic turbos and then do the diffs/transfer case hands down (provided brakes were half decent etc). Absolutely rate the drivetrain after doing it.

[Piggaz]

It's such a case of not knowing what you DONT have until you drive something that's sorted. I've lost the amount of times I keep banging on about diff's, especially the front for GTR's. They're not 4WD, they're 2.5 or 3 WD at best on comparison.

[Ares180BPM]

What do I replace the active rear diff with ?

[GTSBoy]

Any diff at all. Anything, even from a Ford Model T, would be better.

[Piggaz]

Being a V-spec, it isn't just buy a diff centre and chuck it in. You need a Non V-spec diff housing and possibly the shafts, I know I did.

A mate from WA went from a Nismo GT pro to a Quaife rear and he prefers the Quaife.

[Ares180BPM]

To be clear, I don't want to move away from the active diff...

[GTSBoy]

That's not really clear at all. Your last 2 posts are incompatible with each other.

[R31Nismoid]

To be clear, I don't want to move away from the active diff...

Yes, you do.

Trust us. We've been there and done it.

I put a non-ALSD rear into my R33 GT-R... Believe it or not, the non-vpsecs are actually better from a modification point of view as the A-LSD is just trash.