Back End Feels Light

[owen1r]

would they be good for track

Yes, I believe they can do suitable spring rates/damping to suit track only use. Perhaps email them.

[AMR33]

Just had a look at them. I think they wil be suitable for the track work I do. But I think I can find something with similar specs thats second hand for a lot less. Chances are I will have to upgrade later on so if I can find something second hand now that would be the better option.

[warps]

What is this fascination people have with second hand suspension? In most cases a set of new dampers into your old suspension will be miles ahead of crappy second hand shit that's been in 20 different cars.

Good suspension costs money. If you can pick up MCA for $1,500 then that is an absolute bargain. Murray has been building world class suspension systems for top level race and rally cars for years now. The fact that you can pick up anything with his name on it for $1,500 is staggering. I know it's not his top shelf gear, but for him to put his name on this stuff would give me the confidence to use it.

Don't throw money away on another set of second hand crap, and inherit someone else's problems again. My local suspension bloke tells me that he loves cheap second hand ebay stuff. He sells heaps of brand new gear when people buy second hand stuff, then take it to him to install and set up. He then proceeds to show them how worn out / damaged / poorly built it is, and ends up selling them brand new gear. He has bins full of ebay junk, and sells plenty of performance stuff as a result.

I don't know why you're so fixated on getting adjustable damping. Do you really think that your arse is going to tell you whether you have optimum settings in your suspension? MCA will be able to match the valving to suit the car and springs, and that will get you close to the mark. If you're an experienced racer, then you can fine tune from the base settings, but most people won't feel the difference that one click in settings makes, apart from the placebo effect.

Have you actually called Murray to talk to him? He's always more than willing to help people out, and what he doesn't know about suspension design probably hasn't been written yet. You might even find that his gear can be upgraded down the track, eg fitting external canisters. I don't know if that's the case, but certainly worth asking.

Trust me, you wont find anything with similar specs to the MCA gear for "a lot less". You will find some flogged out, unknown spec second hand chinese junk for a lot less, but I know which I'd rather put my money on.

If you can't afford to buy the decent gear (hell, $1,500 isn't a lot of money) then save up for a while and miss a few events. It wont'; be the end of the world. You will be a lot better off for it. Which would you rather; getting scared in an ill handling pig of a car doing 15 track days a year, or going 2 seconds a lap faster, having the time of your life in a sweetly balanced, reliable car only 5 times a year? I know which I'd pick

Sorry for the rant. Just your reasoning makes no sense to me.

[AMR33]

The reasoning is that I am a beginner when it comes to driving on the track. So there is a lot of testing and learning to be done. And if I can find something that will do in the short term for cheaper then why not go with that? But then the question becomes, why not get something decent and pay extra at the start and not having to change again later. I do get that. I'm exploring options as any prudent buyer would I guess.

[djr81]

The hard part in learning is being able to establish what is good, as opposed to what is better.

For example, a second hand set suspension set up may be better than stock. But how close is it to being good? And how, if you are learning, will you know if you have got a good set up or not?

I don't have a good answer to that because I have been caught many times thinking something was pretty good only to make a further discovery/change and the realisation that it was, in fact, pretty crap.

Having a trusted supplier of equipment or the opinion or someone in the industry can help. But I have never met someone selling stuff who don't think its the dogs bollocks.

[niZmO_Man]

If you were in Sydney and had an R32 GT-R, you could have my TEINs for $500 .

[Hadouken]

My ass tells me if my suspension is set up right

[AMR33]

I think your on the money djr81. I want something better than what I have now (which is almose anything) but obviously trying other setups will answer the question of what is better. It just keeps going

[djr81]

Its the age old issue. You want a good result and learning can be half the fun. But learning by making every mistake in the book isn't so much fun. Or cheap.

You could do a lot worse than the MCA stuff. You could do a lot worse than a Bilstein shock and Eibach spring combination.

I would, at the least, talk to MCA. I am guessing the talk here is about their Blue series?

http://mcasuspension.com/blue-series/

Among the question I would ask are:
What are the spring rates he recommends for the 33 GTST.
Is the valving linear/digressive?

Ask if there is an option to replace the uniball with a rubber bush.

Are there sway bars he recommends with the shocks - also castor/camber/toe settings and do you need many bushes to achieve those? I wouldn't expect he would offer these over the phone but it is important if/when you buy them.

Owmuchisit.

[AMR33]

Thanks mate. I sent MCA an email this morning with some of these questions. I should hear back from them soon and I'll ask the rest of the questions.

But most importantly, I need to know the answers I want to hear. So can you tell me:

What sort of valving is better (for my application)?

Is replacing the uniball with rubber bush to reduce noise etc?

Cheers

[djr81]

Digressive - but it doesn't mean linear is all bad.

Uniball have a reputation for a short life - followed by creaking/clunking. Mostly this is the cheap end of the market and the MCA's are specced better (See their website) But to be honest you just don't need them so why take the hassle on board is you don't have to?

[GTSBoy]

What sort of valving is better (for my application)?

Is replacing the uniball with rubber bush to reduce noise etc?

Answer to Q1: High quality valving. Unfortunately, there isn't an easy answer that we could give you that you could understand (or even really that I can understand in order to try to tell you). Perhaps you need to read the sticky thread about shock absorbers that SK did. It goes into some details about why some types of damper are better than others. But it doesn't and couldn't go into the fine details of how you would design a valve stack to achieve a certain goal (like the Bilsteins have, or presumably Murray's dampers have).

Answer to Q2: Yes. Positive (stiff) location of the top mount of Skyline suspension units is not required in the same way that it is on Mac strut cars. On Mac strut cars the top of the strut is oone of the major suspension locating points. On a Skyline it's just where the spring loads go. As such you can go slightly softer in setup (rubber rather than anythiing firmer) to gain some benefit in NVH without costing too much in the way of suspension/alignment vagueness.

Edited October 31, 2014 by GTSBoy

[AMR33]

Nice, thanks guys I appreciate the info. I know you cant give me a yes or no answer and nor am I looking for one, but a forum member is selling a set of Greddy type S coilovers (8/6 Spring Rates and adjustable damper). Was thinking of getting them or something similar as a begginner set up. What are your thoughts?

[GTSBoy]

Same as you've already been told. Are the dampers in them any good? Who knows? What's the risk if they're no good? Pretty much the total value of the purchase. What is 8/6 like on the street? Bloody firm. What's it like on the track? Probably just about right.

One simple rule is that pretty much all Jap tuner brand coilovers are pretty bloody firm. Both in terms of the springs, and therefore also the dampers, assuming that they are well matched to the springs. Most roads in Japan are good quality and smooth. Means you can get away with overdoing the spring rate and damping. Just like being on a good track. Most roads in Australia are poor enough to be bloody annoying on suspension that is too firm.

It's really your call. A lot of guys on hear swear that they find 8/6 coilover setups just fine. I couldn't stand it myself. Maybe it's just the roads we each get to drive on. Maybe I'm just soft. Who knows?

Edited October 31, 2014 by GTSBoy

[AMR33]

Yeah your right mate. Most jap brands Im finding are either 8/6 or 10/8. My main concern is the car being good on the track. I dont drive it enough on the road to care all that much about how stiff it is. That's the thing, it's really going to be a matter of trial and error - something I dont like to hear when im on a budget. Starting to learn that budget and motorsport do not go together all that well....

[GTSBoy]

cheap/fast/reliable

cheap/fast/good

and variations on the theme. Pick any 2, you can't have all 3.

[djr81]

Yeah your right mate. Most jap brands Im finding are either 8/6 or 10/8. My main concern is the car being good on the track. I dont drive it enough on the road to care all that much about how stiff it is. That's the thing, it's really going to be a matter of trial and error - something I dont like to hear when im on a budget. Starting to learn that budget and motorsport do not go together all that well....

Don't get caught thinking that you need hard spring on your car for it to suit the track. For example my GTR has 5kg/mm & 5.5kg/mm springs on it. Most China sets you will find have X & X-2 or X-1kg/mm spring rates front and rear. A case of monkey see, monkey do I would think. Few of the new suppliers would bother tailoring or testing their product much. That may sound harsh but is it more likely they all found the same solution, albeit in different coloured anodising? Hardness of the spring does not correspond to hardness of the driver.

In any case you can change spring rates within a range to suit your preference. There just isn't a problem going a kg or more either way. For example you can ring Bilstein and they will tell you the range in which they reckon their dampers work - it is surprisingly wide. The MCA's are adjustable in the damping rates so you would think you have more scope. And springs are cheap, probably one of the cheapest components you can get - so you can get it a bit wrong and it is not the end of the world.

For info:

Nismo S Tune Suspension for an R33 gtst.

Lowers the car by around 20mm. Spring rate on these are 5.3 Front 4.8 Rear.

Edited October 31, 2014 by djr81

[AMR33]

Cheers for all the info mate, really helpful. I'll keep looking and learning till I find something.

[warps]

To be honest, for a race car the scientific way to get the right spring rate is to work out what rate the tyre has been designed for. You will need to talk to the technical department of the tyre supplier to get that info. From there, work back through your car's suspension setup to calculate what the effective spring rate at the wheel translates to in your suspension setup (lever arms, fulcrums etc.). That will land you in the sweet spot for starting your setup. Then you have to get the damping right to suit the spring constant and weight of the car.

Then you have roll stiffness to consider (as mentioned here already, I believe). This will have an impact on your spring rates, as you don't want the total spring rate at the tyre to change too much.

Then you have the geometry to consider, and more importantly, how that changes through the full range of motion. Changing geometry (camber, caster, toe, roll centres etc) will have a massive effect on handling. Then there's the corner weighting, which is essential to make sure that what you have fitted in the car actually works as designed.

Then we come to driver preference - some drivers prefer a softer, more compliant ride, others like it hard and jittery, oversteer, understeer, etc.

As you can see, there's a lot of black magic involved, and if you're not fairly experienced, you can easily end up with a steaming pile of dog poo, even if you have bought good quality stuff, but got the setup all wrong.

The reason so many are suggesting MCA, apart from the quality of their stuff, is that they know about setup, and are usually very helpful. If you can spend some face to face time, or go to a driver training day where experts drive you car and tell you what changes to make, you will move ahead in leaps and bounds, and will be less likely to waste a lot of money on trial and error.

[AMR33]

If you can spend some face to face time, or go to a driver training day where experts drive you car and tell you what changes to make, you will move ahead in leaps and bounds, and will be less likely to waste a lot of money on trial and error.

That's a great idea, thanks for the tip. Anyone know someone in Perth who can perform such a service? My tire guy is fairly experienced with this sort of stuff so I may have a chat to him soon.