Jump to content
SAU Community

Recommended Posts

this one is i have taken from sydneykid in the coilovers thread. we got to talking swaybars.

Thanks for the advice Gary. Atm im on a full whiteline stabiliser bar kit with urethane bush set, camber front and rear and pineapples set to standard.

the front adj blades on the swaybar im pretty sure though i could only get set up at 2nd and 3rd hole. can the front swaybars be adjusted any further? how can i do it? the rear is at full hard.

What size bars are you using? My guess is the off the shelf 24 mm front and 22 mm rear, which is too narrow an adjusment range for the track work you are doing, grip or drift. You should really be looking at 26 or 27 mm front and 24 or 26 mm rear. I don't recall what model it is, if it's an R32 then you need 4 adjustment settings on the front and 3 on the rear, standard (off the shelf) is 3 front and 2 rear. If it's an R33/34 then you need 6 adjustment settings on the front and 3 on the rear, standard (off the shelf) is 5 front and 2 rear.

You should also be using spherical bearing links on the bars to give you the instantaneous effect, plus increase the feel as you need as little dampening of the response for track work. They will need regular replacement, even the Whiteline greasable and dust covered ones. Just like brake pads they will wear out, they are a consumable after all.

To give some adjustment for the usage patterns that you have, you can't run spring rates that high, anything much over 5 kg/mm front and 4 kg/mm rear will negate the effect of any adjustment (bars, shocks or geometry) that you do. Use the bars to control the roll, that's their job after all and then adjust the rear subframe geometry to suite the traction requirements. At the moment you have nothing to adjust that will help with your problems.

Cheers

Gary

Somethings to think about;

You would need to use twice the spring rate to achieve the same anti roll as a stabiliser bar. Why? Because the inside wheel goes down the same amount that the outside wheel goes up. So a stabiliser bar has twice the movement for the same amount of roll as a spring, hence twice the amount of resistence to roll. Only the outside spring resists the roll, the inside spring does nothing.

When you are not going around a corner, the stabiliser bar does nothing, so you get more traction from the softer spring rate.

Stabiliser bars are easily adjustable, spring rates are not. If, on any given day, you need more or less front or rear anti roll you can't easily, quickly or cheaply adjust it with springs. That's why (when the regs allow) race cars have driver adjustable stabiliser bars.

Diagonal weight transfer is best resisted with anti roll, not spring rate. Under corner exit acceleration the outside rear tyres take a large amount of weight transfer, this manifests itself as lift to the inside front tyre. Reducing inside front tyre grip means that the outsdie front tyre is carrying more of the cornering load than would eb the case if the diagonal weight transfer was a resisted by a stabiliser bar. Excessive outside tyre wear and inability to maintain consistent lap speed due to overheating are all systems.

Too little anti roll has side effects. One of which is the need to run excessive amounts of camber, front and/or rear. This reduces the contact patch of the tyre for straight line acceleration and braking.

Running an excessively high spring rate becuase of a lack of antir roll has a few more side effects. One of which is the need to run excessively high rebound damping in the shock absorber to control that higher spring rate. This means the shocks resists (slows down) the downwards movement of the suspension and makes it more difficult to keep the tyre in contact with the road surface. Skipping from small bump to small bump is not good for traction.

I have several more pages in me if necessary, if anyone remains unconvinced.

Cheers

Gary

Selby's swaybars (not sure if they make swaybars for Skylines) -

http://www.hotfrog.com.au/Companies/Selbys-Swaybars

K-MAC swaybars (As far as I know the prices on the website are in US dollars

and they make swaybars for R32, R33, R34 in non adjustable and adjustable).

K-MAC website -

http://www.k-mac.com.au/

Swaybar prices -

http://www.k-mac.com.au/pages/tuning/listofkits.htm

Also I noticed they can custom make springs.

Edited by SKYPER
Selby's swaybars (not sure if they make swaybars for Skylines) -

http://www.hotfrog.com.au/Companies/Selbys-Swaybars

K-MAC swaybars (As far as I know the prices on the website are in US dollars

and they make swaybars for R32, R33, R34 in non adjustable and adjustable).

K-MAC website -

http://www.k-mac.com.au/

Swaybar prices -

http://www.k-mac.com.au/pages/tuning/listofkits.htm

Also I noticed they can custom make springs.

I thought Selbys was Whiteline?

Anyway thanks for the info and links .

they are hollow bars.

size f: 24.2mm

size r: 27.3mm

i use the gtr spec ones but they bolt onto my gts fine

gts spec ones are

f: 27.2mm

r: 23.0mm

Where did you snap these up from and how much did they set you back???

they are hollow bars.

size f: 24.2mm

size r: 27.3mm

i use the gtr spec ones but they bolt onto my gts fine

gts spec ones are

f: 27.2mm

r: 23.0mm

Front GTR (4wd) bar won't fit a GTST (2wd), plus it is too soft a rate.

Cheers

Gary

Gary,

I have forgotten....what are the size of the sway bars in the GB that I have? :P

From memory, 24 mm solid front adjustable and 22 mm solid rear adjustable.

Minimum adjustment is equivalent to a 27 mm hollow bar, with 6 steps of around 8% increase each on the front.

The rear is equivalent to a 24 mm hollow bar, with 3 steps of around 12% increase each on the front.

All the Jap hollow bars I have tried are grossly underdone. As an example, we swapped John's 300ZX hollow bars for some solid bars, backed off the spring rates a bit and it was 1.5 seconds a lap faster at Philip Island.

Cheers

Gary

  • 2 months later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Ha, well, it's been.... a bit of a journey. Things have taken much longer than I'd hoped. I'll probably put up a thread at some stage. Hopefully soon. The car's not done any kms since my update in June though, put it that way.
    • Here's the chart for fuel pressure vs. current draw, assuming your base fuel pressure is 3 bar and you run like 0.5bar boost on WOT, you should only momentarily hit 9amps here and there. (Ignore my prev post, I cannot read a chart these days it seems)
    • Those comp test results are not hideous. Whether they are accurate or not (ie, when that comp tester says 140 psi, is the real pressure120, 140 or 160?) is unknown to us. The state of the battery used to crank it over is unknown, etc etc. Many people around here would say that the absolute values and the spread are perfectly fine to just add boost and keep going. I personally would be happier with a narrower spread than that, but even the diff between 125 and 145 is not terrible. That one cylinder at 125 though, has probably copped some damage relative to the others. You should inspect the valves seeing as you've got it open. Do you know how to measure installed ring gaps? That, and an inspection of the rings themselves, is how you will determine whether they need to be replaced. If you're not good to do these things, take the block and the pistons and rings to a shop that is, and ask them for the go/no-go on them. Do the bores need a hone at all? If so, you might well be justified in getting some different pistons in order to get away from the ring supply problem. Whether you're happy to spend a lot more money right now, on more gear, rather than less money, but an amount that looks stupid given that you will only get a handful of rings in exchange for that money, is for you to decide.
    • also possibly backed up to my filler and shat down it! 🤣
    • Ok so i would love some advice here please, i purchased an R33 a few months back and its had a few mods done to the engine, its an RB25det running a Master ECU, 1200cc injectors, bigger turbo, oil cooler, oil filter relocation kit, Spool H-beam rods, acl/ross pistons. When i removed the motor from the vehicle (as its getting a respray) i thought i would compression test it and these are the following results. Cylinder 1-145psi, Cylinder 2-143psi, Cylinder 3-125psi, Cylinder 4-145psi, Cylinder 5-140psi, Cylinder 6-135psi this test was done with the motor on the ground and powering up the starter motor. I dropped the sump and found broken oil squirters on cylinder 3,5 and 6. I was told my rings are probably worn so i stripped the motor completely to get a new set of rings for it. The trouble is no one has these rings anywhere and they have to be custom made by Ross over in the states and will cost about $600+$200 delivery. My question is how can i tell if my rings are at fault and if they are still ok and is this price ok for a set of rings?
×
×
  • Create New...