Jump to content
SAU Community

Recommended Posts

It really depends how aggressive your shock absorbers are.

For street driven cars most of my customers run between 5 and 7kg in the front and between 4 and 7kg in the rear.

Spring rates should be selected based on corner weights, nothing to do with engine power the car could have 100hp or 1000hp, what matters is the weight over the individual corner and how much load is transfered to it during cornering (this is worked out using a combination of data ride height/suspension travel/motion ratio etc)

You should be able to find a formulas to work it out on the net but you will have to do some research its not really something which can be explained in a short post

8/4 is wrong wrong wrong. GTR is an inherently understeery platform (throttle oversteer notithstanding). As such, you don't want to be running double the spring rate at the front that you have at the rear. If you want to run 4 at the rear, no more than 6 at the front. If you want to run 8 at the front, then no less than 5 at the rear. Then you have to valve or adjust the dampers to suit and then you have to select anti-roll bar rates to tune the over/understeer balance.

and the more power you have, the more traction you need, so the softer the spring should be. But I can't see why you would expect much traction with 500+kw on street tyres on typically variable street surfaces. I'd always assumed that if you want that much power you *don't* want traction....so put some stiff springs in :)

Are you only interested in straight line?

8Fr 4Rr will be horrible for going around corners (missmatched), like 12Fr 12Rr is horrible (too hard, mismatched). If you're running the Super Streets use the Super Street springs - they are correctly matched front to rear and they'll match the valving - 6Fr 4Rr IIRC.

A mate of mine has a 600kw at all 4s with 6kg all round. Hooks up ok.

What tyre is under it has more to do with how much traction you have rather than spring rate. GTRs at this level squat hard under WOT so you still need a bit of stiffness.

I have 6s all around too.

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

    • The final part arrived today to un-clampify and simplify the intake Who would have though a 1/2" hose stainless bulkhead fitting designed for below waterline bilge pumps would be what I needed Test fit on a 3" offcut I had laying around to see if it would work, and it worked a treat All going well the intake will be on its "final version" tomorrow 
    • Good luck on the weekend mate
    • Must have been an absolute nightmare to drive when the power steer was out, the rack ratio/wheel size/caster is all set up for power assistance
    • Welcome to SAU, what are you looking at buying?
    • I checked the injectors again (1 and 2, since they’re easiest to access) to make sure they weren’t clogged. Even though the entire fuel system had been cleaned, I wanted to be certain. Everything looked clean, so I reinstalled and connected everything. When I started the car to confirm everything was okay, it immediately revved up high, so I shut it off straight away. I checked to see if I’d missed a vacuum hose or something, but everything was connected. On the second attempt, the car ran without the high idle, but I noticed a distinct “compressed air” sound coming from the engine bay. Tracing the sound, I pushed injector #6 forward slightly and the noise stopped — it turned out it wasn’t seated properly, despite the fuel rail being bolted down. While holding it in place, the car idled steadily without stalling and ran for over 5 minutes. At this point, I pulled all six injectors out just in case I hadn’t seated them correctly or dirt had gotten onto the O-rings. Unfortunately, I discovered that I had damaged 3 out of 6 injectors (the OEM 270cc ones) during installation. So yes, this was my fault. Since only the pintle caps were damaged, I’ve ordered a Fuel Injector Service Kit from NZEFI to refurbish them. In the meantime, I reinstalled my new injectors – the car now idles fine for over 15 minutes without stalling. I have not attempted to drive it so far. It’s not perfect yet, as it hesitates when the throttle is pressed, but it’s a big improvement. Unplugging the IACV with the new injectors idles at around 800rpm, even with the IACV screw tightened fully. But this is probably due to tune.
×
×
  • Create New...