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So you guys reakon dont get any kind of adjustable coil overs, and keep factory suspension? Are After market shocks and with some after market springs to match preferred over say bc golds or tein super streets in a drag / street setup situation? When I bought the car it already had some RS-R springs installed in it which I must admit im not to happy with as they are very uncomfortable and bouncy and I have 255 tires on the rear but still lose alot of traction at times. Has gotten a bit better since I started buying better tires. But still feel it could be improved on.

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stock shocks and springs in the rear should be the easiest setup to launch down the strip.

i am also looking at the BC's from JJ as i use to have a set of the 'dreaded' G4s and with some road time tuning i actually had people on the evo forums believe i had ohlins in there.. HAHA.. it just took quite abit of time to tinker with spring seating and every click of the damper made a difference. by no means am i saying they are as good as ohlins.. but they were good enough to fool the average joe and did the job quite well

as for that external gate, thats rather nifty isnt it lol. im sure that will fetch a pretty penny when ur done with it :thumbsup:

also, read the thread i link to below.. it will give you a better idea of the SAFC capability.. help you to decide, you seen switched on enough.

http://www.skylinesaustralia.com/forums/Ru...fc-t308500.html

stock shocks and springs in the rear should be the easiest setup to launch down the strip.

i am also looking at the BC's from JJ as i use to have a set of the 'dreaded' G4s and with some road time tuning i actually had people on the evo forums believe i had ohlins in there.. HAHA.. it just took quite abit of time to tinker with spring seating and every click of the damper made a difference. by no means am i saying they are as good as ohlins.. but they were good enough to fool the average joe and did the job quite well

as for that external gate, thats rather nifty isnt it lol. im sure that will fetch a pretty penny when ur done with it :thumbsup:

also, read the thread i link to below.. it will give you a better idea of the SAFC capability.. help you to decide, you seen switched on enough.

http://www.skylinesaustralia.com/forums/Ru...fc-t308500.html

Hahaha thats good aye. Ive heard good things about ohlins but they cost a mint and also ive noticed apart from the teins most japanese suspension have quite hard springs.

Lol yeah the gate is a odd one aye. Need to get a electronic boost controller though as it has a 0.8 bar spring but most of the time my car runs 9 psi. I think 0.8 bar is 11 psi and it only sometimes runs that and if so its usually in 3rd gear onwards and mostly on cold nights lol. But the car still amazes many people for something that runs 9 psi.

Dicked a lot of good cars which people had done quite a bit to which is why I dont regret buying the R33 lol. Some of them need to learn to drive though hahaha.

bullshit if he is dragging keep stock suspension so the car squats.. :( scan wasteland thread if u dont know what im talking about here...

i know the wasteland thread lol....

he's all about drags, so i said keep the stock coilovers, but upgrade camber, castor, toe, and get sways and pineapples....

so not stock at all.... just no aftermarket coilovers that are too stiff for launches...

clearly this is not what i would do... just an easy way to get the car to launch (as i run 6/8 coilovers at bees dick clearance)

doesnt the standard computer hit boost cut at over 200kw? unless u bypass it ofc but thats pretty silly

Dont know aye thats the first ive heard. I dont know how it would work as the stock ecu doesnt have any way of measuring actual boost does it? Feel Free to correct me if im wrong please as Im not 100% sure.

i know the wasteland thread lol....

he's all about drags, so i said keep the stock coilovers, but upgrade camber, castor, toe, and get sways and pineapples....

so not stock at all.... just no aftermarket coilovers that are too stiff for launches...

clearly this is not what i would do... just an easy way to get the car to launch (as i run 6/8 coilovers at bees dick clearance)

Tru tru what kind of coilovers you running? Im not all about drags. Would be interested in a bit of circuit racing to. Would be doing more drag racing than Track / Circuit Racing though. Just really want something that a very good all round compromise for drag, track, and everyday street driving.

Tru tru what kind of coilovers you running? Im not all about drags. Would be interested in a bit of circuit racing to. Would be doing more drag racing than Track / Circuit Racing though. Just really want something that a very good all round compromise for drag, track, and everyday street driving.

My advice would be to make sure you dont get ridiculously stiff coilovers. The car I bought came with them and its only good when the roads are super smooth. If they are not you get axle tramp on acceleration as the tyre bounces over the bumps.

I would seriously consider leaving the stock suspension if its mainly a street/drag car.

Cheers for the sugestions you guys.

What about some Nismo Springs or Suspension? Any one know much about them? I seen them on Nengun and they look like they use softer springs then most aftermarket coilover / aftermarket spring setups. They are also damper adjustable.

Dont really care about adjustable height as im not gonna mess round with height as I am quiet happy with how Low my car is anyway. Just that the currenct springs in there are far to harsh for my liking.

Dont know aye thats the first ive heard. I dont know how it would work as the stock ecu doesnt have any way of measuring actual boost does it? Feel Free to correct me if im wrong please as Im not 100% sure.

it doesn't actually go off a boost pressure but off the afm signal. once it gets to a range it thinks is too high it packs up it's bat and ball and goes crying home to mum. if you are chasing 230kw you will struggle with the stock ecu. if i was you i would sell the safc and invest in a nistune. a lot of people will also say PFC, but a nistune will do pretty much the same thing at about half the price. you'll just need to get yourself a z32 ecu to put the nistune board into. depending on where you are, you could have a talk to uras as he does a bit of work on them (pretty sure it's uras)

it doesn't actually go off a boost pressure but off the afm signal. once it gets to a range it thinks is too high it packs up it's bat and ball and goes crying home to mum. if you are chasing 230kw you will struggle with the stock ecu. if i was you i would sell the safc and invest in a nistune. a lot of people will also say PFC, but a nistune will do pretty much the same thing at about half the price. you'll just need to get yourself a z32 ecu to put the nistune board into. depending on where you are, you could have a talk to uras as he does a bit of work on them (pretty sure it's uras)

Yea I only just recently read about the nistune and how you are able to use a z32 ecu on a r33 gts25t with minor mods. I contacted nistune today as im in New Zealand and am gonna get them to send me the daughter board and software to tune etc. I am aquiring a z32 ecu from ebay and will get one of the EIR guy's from work to solder and modify the ecu accordingly and then I will use that when I need bigger injectors and afm and turbo and power etc.

For the mean time Ill jsut use the safc2 I was given and run it with my basic mods that I got and see if I notice any improvements.

Cheers for your help.

So you want your car to "squat" to put more weight over the back wheels when it launches to give more traction? oh god... does anyone here know any better? or is there actually no one here that knows anything about suspension dynamics?

The whole reason why the car squats is because of load transfer, this is because forces acting through your CoG makes a torque moment around the pivot point (your tyres and the road) essentially your car acts as a big lever, with the force coming from acceleration G's and although these acceleration forces act on all parts of the car it can be summed up through the cars centre of gravity.

What this does (even if your in a go kart with no suspension and no squatting what so ever) it unloads the front tyres and loads up the rear tyres, could be up to 30% load change between front and rears, probably even higher (this depends on wheel base and CoG height). This extra load on the rear is what adds to the traction, this happens even if you replaced your springs with metal rods and your whole suspension was rock solid.

(These are the same physics principals that are in action when you fly around a corner and your outside wheels get loaded more and inside become unloaded, Acceleration force is now laterally hence the side to side load transfer as opposed to the longitudinally load transfer when accelerating)

Having springs just means this force is being used to compress the springs, so while your springs are compressing you are wasting time, have less load on the tyres and have more chance of spinning the wheels. Having stiffer suspension means the load can transfer to the wheels instantly hence giving better more controlled acceleration off the line.

Then you can go into weather you are over powering your tyres or not and setting up suspension to counter act that, but this is still some of the basics of it all and the hole goes much much deeper....

anyways if you want to know more there are many mannnyyy great books out there, I can recommend some if you wish.

Edited by ascenion24
So you want your car to "squat" to put more weight over the back wheels when it launches to give more traction? oh god... does anyone here know any better? or is there actually no one here that knows anything about suspension dynamics?

The whole reason why the car squats is because of load transfer, this is because forces acting through your CoG makes a torque moment around the pivot point (your tyres and the road) essentially your car acts as a big lever, with the force coming from acceleration G's and although these acceleration forces act on all parts of the car it can be summed up through the cars centre of gravity.

What this does (even if your in a go kart with no suspension and no squatting what so ever) it unloads the front tyres and loads up the rear tyres, could be up to 30% load change between front and rears, probably even higher (this depends on wheel base and CoG height). This extra load on the rear is what adds to the traction, this happens even if you replaced your springs with metal rods and your whole suspension was rock solid.

(These are the same physics principals that are in action when you fly around a corner and your outside wheels get loaded more and inside become unloaded, Acceleration force is now laterally hence the side to side load transfer as opposed to the longitudinally load transfer when accelerating)

Having springs just means this force is being used to compress the springs, so while your springs are compressing you are wasting time, have less load on the tyres and have more chance of spinning the wheels. Having stiffer suspension means the load can transfer to the wheels instantly hence giving better more controlled acceleration off the line.

Then you can go into weather you are over powering your tyres or not and setting up suspension to counter act that, but this is still some of the basics of it all and the hole goes much much deeper....

anyways if you want to know more there are many mannnyyy great books out there, I can recommend some if you wish.

That was really interesting to read. Sounds like theres alot to picking the correct suspension. Thanks for that. So are you trying to say that centre of gravity and height of the car also has alot to do with traction and launching? Im open to any ideas and if you do know any good books or read ups on the internet about selecting a setup for my car that would be awsome as well.

K-LESS, those things and many many more all contribute to traction, launching, handling... the works.

A very good read which is highly recommended from lots of people is from the late Carroll Smith, titled "Tune To Win".

Carroll Smith was a race car engineer, he consulted for formula 1 teams, worked with shelby on the GT40. All round extremely intelligent guy.

He has a series of books but after reading them all unless your planning on building a race car you can count two of them out as there related to nuts, bolts, metallurgy failure modes etc.... But the one I recommended explains all the basics and sometimes more advanced principles of everything from suspension, load transfers, brakes, shocks, springs and much more.

You have to remember, there are so so many factors involved, I am by no means an expert in the field.

By just lowering the car your changing your camber. Just by re setting the camber wont remove this issue all together because you have already moved somewhat through your range of motion therefor when the car squats taking off your change in camber will be greater for the same amount of travel then compared to if your suspension was compression from stock height.

Theres diagrams that explain all this in the book and they really do help to drive the ideas home.

I read through these books for uni as we had to design a race car from scratch to compete in the Formula SAE, but I didn't design the suspension side so my knowledge is limited, (im a powetrain guy) someone could come along right now and explain why a bit of squat is good (and it could be) but unless they have a proper understanding of why, dont listen, always seek out the truth and reasoning behind it first.

Edited by ascenion24
K-LESS, those things and many many more all contribute to traction, launching, handling... the works.

A very good read which is highly recommended from lots of people is from the late Carroll Smith, titled "Tune To Win".

Carroll Smith was a race car engineer, he consulted for formula 1 teams, worked with shelby on the GT40. All round extremely intelligent guy.

He has a series of books but after reading them all unless your planning on building a race car you can count two of them out as there related to nuts, bolts, metallurgy failure modes etc.... But the one I recommended explains all the basics and sometimes more advanced principles of everything from suspension, load transfers, brakes, shocks, springs and much more.

You have to remember, there are so so many factors involved, I am by no means an expert in the field.

By just lowering the car your changing your camber. Just by re setting the camber wont remove this issue all together because you have already moved somewhat through your range of motion therefor when the car squats taking off your change in camber will be greater for the same amount of travel then compared to if your suspension was compression from stock height.

Theres diagrams that explain all this in the book and they really do help to drive the ideas home.

I read through these books for uni as we had to design a race car from scratch to compete in the Formula SAE, but I didn't design the suspension side so my knowledge is limited, (im a powetrain guy) someone could come along right now and explain why a bit of squat is good (and it could be) but unless they have a proper understanding of why, dont listen, always seek out the truth and reasoning behind it first.

Hey ascenion24

Thanks for your help. I will try find the book and have a read. You information and help has been very knowledgable. Hopefully I can learn something new as when it comes to suspension set ups, handling etc i really do not no much at all about it. I am still learning and am always open to learn more to help me build a descent car.

Cheers and Thanks Again.

My car has been completely modified except the major engine internals. The guy I bought it from said it was making 240atw at 14psi. Toshi, who will be tuning my car again because the fuel pump has been upgraded, said he can bring the car to a steady 16psi and that should make 250 - 260rwkw. My car is all controlled with the PFC.

K-LESS, those things and many many more all contribute to traction, launching, handling... the works.

A very good read which is highly recommended from lots of people is from the late Carroll Smith, titled "Tune To Win".

Carroll Smith was a race car engineer, he consulted for formula 1 teams, worked with shelby on the GT40. All round extremely intelligent guy.

He has a series of books but after reading them all unless your planning on building a race car you can count two of them out as there related to nuts, bolts, metallurgy failure modes etc.... But the one I recommended explains all the basics and sometimes more advanced principles of everything from suspension, load transfers, brakes, shocks, springs and much more.

You have to remember, there are so so many factors involved, I am by no means an expert in the field.

By just lowering the car your changing your camber. Just by re setting the camber wont remove this issue all together because you have already moved somewhat through your range of motion therefor when the car squats taking off your change in camber will be greater for the same amount of travel then compared to if your suspension was compression from stock height.

Theres diagrams that explain all this in the book and they really do help to drive the ideas home.

I read through these books for uni as we had to design a race car from scratch to compete in the Formula SAE, but I didn't design the suspension side so my knowledge is limited, (im a powetrain guy) someone could come along right now and explain why a bit of squat is good (and it could be) but unless they have a proper understanding of why, dont listen, always seek out the truth and reasoning behind it first.

lol... i realise this... i was simply reffering to stock coilovers vs stiff ass ones :D

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