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Ok, time for an update...

Went a did another track night a while ago with some new RE55S rubber and it didn't go too well. Had massive issues with a lack of rear traction and ended up going backwards into the sand trap at turn 1 at the end of the night. I have the track battle coming up in a few weeks so I have a few options to try and help me fix the issues

1. Keep current set up and drive around the issue

2. Replace the rear subframe with a S15, which have better geometry and should provide more traction (which will push the track out 5mm) but run +5 offset wheels and run 235/45 tyres on the back

3. Replace the ally upper bush at the top of the front subframe mounts with whiteline spacers to shift the geometry and run +5 offset wheels with 255/40 tyres

Really the only options are 2 and 3... Just trying to work out if the extra 20mm if tyre is worth the compromise in the rear suspension geometry?!?

Any ideas, help or suggestions would be great?!?

Out of interest...are you having trouble in 3rd gear? Or are you trying to get out of corners in 2nd?

3rd gear on 20psi... I don't even bother with my high boost setting haha

If I go even half throttle through corners it will step out on me a little, any more than that will usually have me spinning all of 3rd down the main straight :(

2nd is a disaster but I only use it once after a hair pin so I'm usually pointing straight before I hit the go peddle :whistling:

Simon I have some questions for you as Im going to be installing an rb25 into a friends s15 very soon, where did you get your plenum from? Are all china ones the same quality or are some better than others? Did you have to get yours machined? Good idea to get done or not needed? Does the stock TB bolt onto it?

Also, what ecu / afm are you running? From memory it was an r32 nistune with z32 and a seperate VCT window switch ? MSD ?

Edited by snozzle

sounds like easiest thing is to change sport and go sideways :whistling:

but in all honesty even though mine is a drift setup when ive softened the dampeners down driving grip on 235 / 45 Rsr's i have trouble in 3rd so you would have more trouble with more power... wouldve thought 255/40's at least?

also what about spring rates or amount of dampening ?

what about running 18's for more grip and can fit wider tyres?

what rear alignment you running ? have you tried different alignemnts ?

im runnning -0.5 camber total and 4 mm toe in total and thats trying to be as grippy as possible

interested to see what the differences are.. sorry if im no help . lol

What have you got in the way of diff, cradle bushes, and arms. You are running Greddy shocks arent you? What spring rates and swaybars have you got. Ride heights?

I think we would all be guessing but if there was some in car video you could get an idea of just how throttley it is in the corners.

Simon I have some questions for you as Im going to be installing an rb25 into a friends s15 very soon, where did you get your plenum from? Are all china ones the same quality or are some better than others? Did you have to get yours machined? Good idea to get done or not needed? Does the stock TB bolt onto it?

Also, what ecu / afm are you running? From memory it was an r32 nistune with z32 and a seperate VCT window switch ? MSD ?

Got mine off ebay, can't seem to find the buyer but it had already had the faced machined (which is a very good idea to ask). I think vulture motorsports on here sell decent ones, there are some dodgy ones around though. I have the VH45 throttle body so I didn't need an adaptor but you will need one to use the stock RB25 one, the cost of the VH45 was $100 and the stock adaptor was $100ish so it made the choice easy :)

I'm running a Nistune RB20 ecu and sensors with a Greddy MSS switching VCT

sounds like easiest thing is to change sport and go sideways :whistling:

but in all honesty even though mine is a drift setup when ive softened the dampeners down driving grip on 235 / 45 Rsr's i have trouble in 3rd so you would have more trouble with more power... wouldve thought 255/40's at least?

also what about spring rates or amount of dampening ?

what about running 18's for more grip and can fit wider tyres?

what rear alignment you running ? have you tried different alignemnts ?

im runnning -0.5 camber total and 4 mm toe in total and thats trying to be as grippy as possible

interested to see what the differences are.. sorry if im no help . lol

Drifting is for cookers, no offence :nyaanyaa:

Yeah if I run +35 offset rims I should be able to squeeze some 255s under the guards.

I've got 0.75deg rear with 2mm total toe in at the rear. I'm running 6kgs springs in Greddy Type-S coilovers, I do have to soften the dampers (I think they were set to about 10 of 32)

The only other thing that may be causing my issue is my aftermarket rear LCA's... I'm starting to wonder if they have done some funky shit with my geometry (moved roll centre etc). I have some spare GTR ones at home that I might smash in this weekend

Edited by SimonR32

What have you got in the way of diff, cradle bushes, and arms. You are running Greddy shocks arent you? What spring rates and swaybars have you got. Ride heights?

I think we would all be guessing but if there was some in car video you could get an idea of just how throttley it is in the corners.

Diff is stock GTR 4.11 jobby, cradle bushes are Kazama ally lock bushes, D-project rear upper camber, traction and rear LCA's (all rose jointed), Greddy shocks with 8/6kg, stock front swaybar and GTR rear, ride heights are reasonable (I'll check tonight but they are about 1.5cm between top of tyre and guard).

Unfortunately no in car video with the rear grip issue :(

Well i think the best starting point would be to get a proper wheel alignment in the rear end since you have all those adjustable arms. From there I would also be replacing the alloy cradle bushes with Whiteline type bushes and angling the cradle. The reason I have never installed my alloy bushes is you lose the ability to tilt the subframe and i generally credit the power down of my car to this simple mod of keeping it simple.

Also, i would throw away the bigger rear GTR swaybar. Either go std all round or get some Whiteline ones all round

i rememeber reading somewhere optimum wheel specs for grip on gtst is 17/8/235/45 front and 17/9/255/40 rear with 35 or 38 offset..I find alot of rwd track cars i see run these sizings so thats what I would run

and GTR rear bar will def give you oversteer tendancies as well..either ditch it or just add a thicker front to even it out..but not too thick, 24mm adjustable ..

The rest will just be finetuning in your settings..and maybe those rear bushes as Roy mentioned

I think it could be sorted without the need for drastic moves like subframe changes anyway, try not to overthink it..

just my 2c and im definately no expert ;)

Drifting is for cookers, no offence :nyaanyaa:

knew you'd say that thats why I put it in hahaha

i agree with roy, start simple first

soften dampners a touch, go back to std rear lower arms (sell your ones to me), put wider tyres on, smaller sway maybe whiteline 22mm rear ? but the whiteline pineapples to tilt your cradle I think is a plus .. I have these and tilted cradle to 'grip or squat' and find my car has alot more grip then other 'cookers' cars out there

either way goodluck and come say hi at trackbattle / adgp ...... im only half a cooker

Yeh, I have a very basic rear end in my GTSt, not the sort of torque you have with the T67/RB25 but with 17" Semis my car doesnt wheel spin in 2nd let alone 3rd.

I would bin the LCAs and even the upper arms, if you still have the std arms then just throw a bush set in them. If you want I can send over a set of upper arms with adjustable bushes in them that you can trial.

Using std bits may mean your car isnt the quicket corner speed wise, but you wont be the slowest. And you can be assured the car will generally be well behaved. The slowest guys are the often the ones with all the stuff under the sun in them and as a package it just doesnt seem to work.

Hell if you ask nicely I may even send over a spare Whiteline front swaybar for you to trial if you want

Have not done a lot to the car lately apart from install the coilovers but took it to a motorkhana for a bit of fun yesterday :)

6155874680_0e25385e0f_b.jpg

6155874394_be90f1271e_b.jpg

6155324395_01bf35124a_b.jpg

love the green and that bodywork is pretty damn good as well..great shots :thumbsup:

would be great to see it with polished rims with some dish..

is there any full vids on the skidpan, the one in your dp is a tease and I didnt find many more on you utube either

knew you'd say that thats why I put it in hahaha

i agree with roy, start simple first

soften dampners a touch, go back to std rear lower arms (sell your ones to me), put wider tyres on, smaller sway maybe whiteline 22mm rear ? but the whiteline pineapples to tilt your cradle I think is a plus .. I have these and tilted cradle to 'grip or squat' and find my car has alot more grip then other 'cookers' cars out there

either way goodluck and come say hi at trackbattle / adgp ...... im only half a cooker

Yeah that is probably going to be the plan... Wind the dampers back, go back to standard LCA's (how much you want to pay :P), 255/40 on the rear. I've got some whiteline pineapples at home so I'm thinking I'll remove the top front ally lockers and put in the whiteline pineapples to tilt the cradle!

Going to be a busy weekend!

Yeh, I have a very basic rear end in my GTSt, not the sort of torque you have with the T67/RB25 but with 17" Semis my car doesnt wheel spin in 2nd let alone 3rd.

I would bin the LCAs and even the upper arms, if you still have the std arms then just throw a bush set in them. If you want I can send over a set of upper arms with adjustable bushes in them that you can trial.

Using std bits may mean your car isnt the quicket corner speed wise, but you wont be the slowest. And you can be assured the car will generally be well behaved. The slowest guys are the often the ones with all the stuff under the sun in them and as a package it just doesnt seem to work.

Hell if you ask nicely I may even send over a spare Whiteline front swaybar for you to trial if you want

My old GTR gripped really well in RWD and that had even more power and torque so I know I have gone wrong somewhere! I'm going to swap out the LCA's, I'm lucky I have a full set of rear arms out the back on a spare subframe... I'm going to keep the uppers as I find the Whiteline bushes don't have enough adjustment even if you use them on both sides :)

The front swaybar may be an option, I'll try adjusting the rear a bit and see how I go first :thumbsup:

just re - read

std front sway and gtr rear sway - definately contributing to your prob

imo dont reduce your rear increase your front

think Russman runs a bigger front to rear also

for cookers sake i run whiteline 27mm front and rear - just have front adj to soft ( for obvious reasons )

Russman has my old custom swaybars which are bigger then anything you can buy off the shelf.

With regards to not liking to run Whiteline bushes in the rear end? What is so different about your geometry that bushes cant give you the correct alignment? Hell my rear geometry is just fine and I have fixed inner and adjustable outer bushes. Must be something different in the lengths of arms you have run

Russman has my old custom swaybars which are bigger then anything you can buy off the shelf.

With regards to not liking to run Whiteline bushes in the rear end? What is so different about your geometry that bushes cant give you the correct alignment? Hell my rear geometry is just fine and I have fixed inner and adjustable outer bushes. Must be something different in the lengths of arms you have run

Natural camber using stock arms at the ride height I use is about 3deg camber, which 2 kits you can only really wind that back to just under 2deg where I want to run more like 0.5-0.75

Interesting both your thoughts on the whiteline swaybars... Can get a set of 24mm adjustable for $400 delivered hmmmmm

Edited by SimonR32

Ok I think I have come up with a plan... Let me know what you think :)

Set up the subframe as per below, yellow = whiteline bush and red = kazama ally lock bushes

Capture-5.jpg

Buy some Whiteline 24mm adjustable sway bars (front and rear) and run them on the softer setting

Run 255/40's on the back and wind the coilovers to the softest damper setting

My suggestion for the 24mm front bar was just to complement the GTR rear..but i looked it up and GTR rear bar is 25mm, (i thought it was 22mm), so would be better go the 27mm front.

"Rear-wheel drives that oversteer, or pick up an inside rear wheel and spin it, often benefit from a upsized front sway bar"

Maybe just start off with a thicker front first and see how it handles..

http://www.whiteline.com.au/do_segue4.php?make=Nissan&model=Skyline&model_final=SKYLINE+R32+GTS%2C+GTS-T+2WD&vehicle=1%2F90-1%2F93

Can't even see a part number for a 27mm bar, but I do take your point it might just be worth going a Whiteline front with GTR rear hhhmmmmm

Also worth noting that the GTR 25mm is hollow while the White 24mm are solid, so not same same I don't believe?!?

Edited by SimonR32

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