Suspension settings for RE11?

[Stardust]

edited by S

[bobbo]

Go get the car aligned and corner balanced for starters. Tell who ever is doing the work what the car is used for and they'll get you set up or atleast close. Suspension set up is pretty tricky.

[frankiman]

a stickier tire will tend to make the car pull more Gs in corner, thus making the chassis roll and the tire roll over itself, so more camber might be needed

if you get tire sizes alot different from stock, you shoukd keep a similar different in width front/rear not to upset too much the balance,
but if you get much wider rear tires (RWD car) than you'll have to compensate with the front/rear damping/spring rate/camber/roll bar rate to maintain an healty balance

if your just starting doing track, just get an OEM alignment and have fun
you'll get alot faster with experience than performance parts and settings

[Skym]

The suspension (spring, shocks, swaybars and as mentioned above by Franki, alignment, etc) has to be matched to compound of tyre. There's formula's for this, but it requires a shock dyno, spring testing machine, etc, so is a suspension specialist thing (not DIY, unless you know someone with that equipment). I would suggest you find someone with that equipment, knowledge (someone who sets up racecar suspension and they usually they have alignment equipment as well, so can align it for you, based on their experience on that course or racetrack).

[frankiman]

^^ sure Skym, he could do that if he was building a race car, but we are talking about a street car that will seldom see the track

yes any shop should be able to do the OE alignment, they should have acces to all the stats in the system, i got my GTRs alignment by 4 different shops thru the years and they could all find the specs in their system
with a run-of-the-mill OE spec alignment, the car will feel good on the street and the track, and will definetly make your tires last as long as they can
this is a big plus since the RE11 are a softer compound that usually wear fast(er) than OE tires or high performance all seasons, and they are not cheap, you could easily make these tires last over 20,000km (even with track)

good choice on the GTR rims, they are well documented on GTS-T body to fit perfectly, and they are great quality (OEM forged)
but still i would suggest keeping a staggered-like tire setup
i'm not an expert on GTS-T, but i beleive the rear OE tires were a bit wider, but in any case, since the car is RWD i would go with rear tires that are 10mm to 20mm larger than the front
it will give the car a bit of understeer at higher speeds, but will keep you from spining the back wheels like crazy at low speeds

and last but not least, since you are going with a really good performance tire that has alot of grip when heated up (on the track) i'd upgrade the brakes pads too, not only for a better initial feel, but for a longer lasting braking capability and predictabiliy on the track
cuz since the RE11s are so grippy, you'll overload the OE pads quite rapidly

the standard option for street spec - track capable pads are;
hawk hp+
ebc yellow

you can't go wrong with those

[Skym]

^^ sure Skym, he could do that if he was building a race car, but we are talking about a street car that will seldom see the track

It's always good to get expert advice to correct any obvious flaws with setup that they see. Like Whiteline pineapple bushes can help to remove some of the subframe movement if factory bushes are old but haven't failed and to increase grip on rear by changing subframe angle.

i'm not an expert on GTS-T, but i beleive the rear OE tires were a bit wider, but in any case, since the car is RWD i would go with rear tires that are 10mm to 20mm larger than the front
it will give the car a bit of understeer at higher speeds, but will keep you from spining the back wheels like crazy at low speeds

Good advice Franki.

Factory GTS-T tyres are 205/55/R16 front and rear. GTR tyres are 225/50/R16 front and rear. Nismo are staggered (I guess you could call them OEM, as it's a Nissan owned company) on GTS-T.

Staggered setup doesn't produce understeer from my experience, if car is setup correctly (I run staggered setup on my car). But you might be 100% correct with the setup he is running which could cause understeer and even ride height can affect understeer, oversteer, alignment (if using non adjustable stock upper arms on front of car, rear upper arms can be adjusted a little bit via bolt).

good choice on the GTR rims, they are well documented on GTS-T body to fit perfectly, and they are great quality (OEM forged)

I agree, R32 GTR stock rims are a good choice, as are lighter (I remember someone on here weighed them and roughly weigh around 6-7kg each wheel vs 17kg for heavier aftermarket wheels and lighter than GTS-T OEM wheels).

cuz since the RE11s are so grippy, you'll overload the OE pads quite rapidly

Also street pads / OEM pads are low heat range and will over heat on racetrack. Racing pads are higher heat range. When buying brake pads, look at heat range, compound of pad (metallic, semi metallic, etc). They are more important than brand, but compound of pad should vary between brands. OEM brake pads usually don't have metal in the compound (that I know of).

Also add 600+ brake fluid (if brake fluid overheats you get brake fade and that heat gets transferred to brake fluid via calipers. I noticed some who drift in US use water cooled calipers, which seems to be the latest trend), braided brake hoses with teflon cover / protection (to prevent rocks cutting brake hoses, dust entering braid). Also rotors suited to racetrack use (like brake pads they can handle high heat due to I think was heat treatment).

[Skym]

Brake master cylinder stopper helps as well.

Understeer is bad. I had it with stock suspension after removing HICAS (HICAS fixes the understeer problem with stock suspension setup, which could have been fixed via fitting bigger rear swaybar). Without HICAS car wouldn't turn in (felt heavy on front of car and wanted to go wide) on 90 degree corners and when turning 90 degrees at intersections you could feel the understeer. But car was more stable in rear and predictable without HICAS.

If you look at factory swaybars, they are roughly 24mm front, 16mm rear (I might have not measured them in the middle of swaybar, so I would suggest to measure them yourself with vernier caliper to confirm). Basically bigger front swaybar, smaller rear swaybar = more grip on rear wheels thus get understeer. If fit R32 GTR rear swaybar (bigger diameter than stock GTS-T front swaybar) you get more grip on front wheels than rear wheels hence oversteer. If want something in the middle it was 240sx / S13 rear swaybar (can't remember if it was the HICAS or NON HICAS 240sx / S13 rear swaybar, as they are both different diameters and produce different results).

If want an aftermarket solution, Whiteline sell swaybars that give it the inbetween and less bodyroll.

From what I understand, the swaybar helps to stop stops suspension extending on inside wheel and pushing car over which creates bodyroll when cornering. If bodyroll is excessive, sidewall on tyre (outside wheel on front) collapses and car spins out (can do a 360). Swaybars are matched to shock, spring, as stronger the shock, spring is, bigger / stronger the swaybar you need to match.

That's why swaybars are the best bang for buck handling upgrade, as they actually reduce bodyroll by alot (more than changing suspension) and can help to increase grip due to car sits flatter (tyres on both sides of car are gripping). Even just changing the endlink bushes on stock swaybars with new bushes makes a big difference (usually endlink bushes are worn out / crushed on R32 Skylines, so swaybar on front, rear doesn't work properly and is usually blamed on suspension being worn out). I think Nismo sell upgraded bushes for stock swaybars.

Tyres have different characteristics and you fit tyres to suit application. If want some slip to get car to turn in, then grip (to get around corners quicker), Dunlop are best tyres to have due to sidewall, etc design. Bridgestone have no slip but give a soft ride. Only way to find this out is try and test them or ask people who have. Also there's different compounds (number on sidewall of tyre), Franki knows that info well. There are tyres for racetrack, dragracing, etc.

If want something simple that works, can try Dunlop semi slick tyres, BC racing setup which is 8kg front, 6kg rear (the Teins on your car might have those spring rates) and leave HICAS in place (or remove HICAS and fit correct size 240sx / S13 rear swaybar). Can fit R32 GTR rear swaybar, upgraded LSD (for grip, drift and some LSD are adjustable), normal street tyres on rear, change alignment of rear subframe, alignment if want to drift, so by just changing rear swaybar, etc you can switch between drift, grip (my car is the similar, as have 3x swaybar options I can run).