D2 Coilovers

MaysEffect

A great article indeed.
That is the problem with relying on shocks to tune overall force. This is why it's just as important on choosing the right spring setup over anything else. The damper for all intensive purposes should be doing as little work as possible. With cheap coilovers that use both inaccurately gauged dampers as well as inaccurately matched springs usually ends up with poor ride quality over time, if not immediately. Even if you have an poorly adapted damper, you still should be able to get reasonable control if you have the right spring setup and have the damper adjusted to the least intrusive rate.

One of the biggest points on the article is about gas pressure. So many rules of thought still floating around saying its not as important as it is or should be used in other ways other than valve attenuation, when in reality it can make or break your handling, certainly over time. It's also another reason why i'd never suggest anyone use a twin tube shock.

Fun fact- This is vague an slightly inaccurate. But that is an entirely different argument. Fact of the matter, F1 cars generally remove the aid of adjusters because it increases weight and bulk. Teams have entire garage zones dedicated to re-tooling or simply replacing dampers and spring rates at race events. Its never one and done.

Secondly most of the bump and rebound is controlled by the tire, not the damper. The dampers and "roll eliminators" primarily serve to control yaw, roll and pitch. Where as on our road cars the dampers have to control this plus bump and rebound as well as squat and dive independently. So adjusters are still valuable, as they are on anything short of an LMP1 or gp2 car.

2 cents.

D2 coilovers? I would actually like to know how they handle. compared to more expensive kits.

Jhill

I think what hotrodz. Was getting at is the swifts "feel" softer which probably means more compliant. If we take for example a spring that is 400lbs per in and a block of rubber that is 400lbs per inch they may both be the same rating but their ride characteristics couldn't be more further apart.

I know what he is talking about as I have switched spring for off-road bike (which has a much more direct connection to ground than a road car) and I noticed a difference. I actually switched just for the weight savings (to a light weight alloy) but after switching the characteristics and liveliness of the suspension was noticeable, maybe not night and day but it was noticeable (could I notice the difference in a car? I'm doubtful). One would think just speeding up the low speed rebound on the normal spring would do the same thing but it really doesnt, I can't say why but I do know it isn't the same. Ti springs used to always hold a reputation for having a different ride feel as well.

MaysEffect

Goddamnit Jhill i was just now mentally trying to back out of this argument lol. Now i have to go into thought again about potential material properties and here say theories again .

For one rubber does not and will never hold spring tension like metal. So measuring the cycling rates of one to another is irrelevant, regardless if they hold the same pressure at a given measurement (highly unlikely). But in the case of measuring one steel vs another of fairly similar properties, it is much more likely the cycling rate would remain almost identical if they both are rated and designed for linear force output.

Regards to new versus old. It's also possible you guys felt a difference simply because the old spring has settled into fatigue and spring sag, loosing it's original overall force output. That is not the same as saying two new springs with measurably equal rates will behave different enough to noticeably feel under load.

Similar to worn tires compared to new tires of the same size and model, or even a different model. In most cases we're remembering and comparing the end state of the old vs. the immediate state of the new. This is not a fair analysis and in most cases does not show the whole picture.


I actually have to work today so I'll conclude at this for now and allow you guys to rip into my opinions .

Rusty

Just give it up. You're going to get beat until your ears bleed. Retired with 2 engineering degrees. In my experience. What is in a book and what SHOULD happen does NOT always happen as predicted. I've come across too many things in my work that has blown my mind. I've come across other engineers that think like you. Most cases, they don't make it far unless they change the way they think and realize that things are not the way they seem to be sometimes. Experience is the best teacher, along with failure.

Give you credit. You make good points on suspension overall, and have good knowledge on the subject. But there are times, like this. You can not, will not see the other side of things. And are unwilling to accept a different outcome.

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MaysEffect

I'm not sure beat is the right terminology when you guys are not presenting valid or even accurate facts against my argument. I've asked hotrodz 3 times already if he can validate his testing other than the vague statement that swift springs are generally softer. All I've heard so far is that I'm being difficult, argumentative and/or wrong. The closest thing i can do to accurately proving the statement wrong is by going out and actually measuring one against another under dyno tests. I'm not sure winning this debate is worth 150 dollars.

I also stated my only problem with these statements is that it slightly tarnishes the reputation of the company by associating a non tested or inaccurately proven claim that there is something ingenuine of products ratings.

Jhill was so far the only one making valid claims about spring retention with his statements, and i believe i refuted it reasonably.

Hotrodz

One of the things learn as you mature and many don't is you can't argue with stupid. Maybe in thirty years or so you may be worthy of a real conversation. Your ego and need to be superior diminishes anything worthwhile you might have to say. That being said how am I impugning the reputation of any company when several of those companies sell Swift Springs as an upgrade to their own spring. And that will be the last statement from in this thread!

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MaysEffect

Not sure "impugning" was used correctly there, but anytime you question someone or something on how they describe their product or character, you are in some form tarnishing their name. Will they lose sleep or customers over it? Maybe not, but I'm sure enough people value your opinion on this forum to take your word on the matter and would try something else if they find what you say logical. Even on lookers can tell by your stats and signatures that you have a high reputation here and your opinion should be taken seriously. Why would anyone choose to go with Swift springs over something else if they don't hold up to the standardized values like you said? It's not even the cheapest option in the market.

I don't understand the need for hostility and attacks, I've never once spoke you guys name out of term. This conversation could've been over posts ago if you guys would have simply stated you disagreed. Instead the debate was continued with further claims for me to pick at regardless if it's right or wrong, stupid or logical.

I've tried to make all my statements as factual as possible, i don't see how i can make it any less egotistical. If i'm wrong simply correct me like Jhill or add info like Nismo91 and Rusty. Calling my argument stupid only breeds further dispute on both sides.

MaysEffect

And lastly on this debate about debating, this has absolutely nothing to do about wrong or right or getting a leg up on anybody. I'm lodging my objections for new on lookers who are looking for proper information. It's clear that you guys seem to be the leading force in knowledge on this forum. If no one questions you guys every once in a while, nobody would, and improvements aren't made. One persons word will be followed blindly without actually learning anything. If anything this debate has probably enlightened or will enlighten someone in the years to come.

OptionZero

I'm pretty sure no one cares for you because you seem like a dude that needs to walk away from the ******* computer and have a few beers instead of posting 10,000 words about why you're god's gift to this forum.

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cv129

Of all the places this discussion can take place, y'all are duking it out in a D2 coilover thread?

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MaysEffect

Probably right, but i can't drink alcohol.

Jhill

Here mass maybe this will help you. As I said people used to always comment on how ti springs felt different/better than steel and often commented as being "plusher". Now that these new alloy springs are out, which is what swift is and I'm sure it's similar to what I'm using on my bike. They have the same advantage in weight as Ti and I would not doubt similar frequency responses either.

WHY TI?

MaysEffect

Good info, and also good point about it being plusher oppose to softer. That i believe is the correct term. But this doesn't explain how it changes its specific force output when comparing two similarly rated springs. It only explains for any specific rate, you have less mass and subsequently more available travel. Would this actually make 400ib/in rated spring respond differently? Possibly, but what is being changed here dynamically? Wheel rate? The springs mass is balanced 50/50 between unsprung and sprung mass, so 2-5ibs loss in mass on the unsprung side would make a huge difference on its inertia over bumps. The other caveat is fatigue resistance and resistance to sag. Both of these go back to what i said earlier.

So in actuality the new spring would actually be stiffer, possibly resulting in a smoother more responsive wheel control. This intern is misconceived as "softer", but as you pointed out, it is actually "plusher".

Similarly to reducing the mass by adding smaller diameter and lighter wheels and tires, the overall change here is a reduction in weight and inertia.

Jhill

I don't think there is a difference in force output andI don't believe anyone here is actually thinking that. I believe this whole thing got derailed because of nitpicking terminology. I don't believe anyone is actually claiming swifts are "softer" what they mean is they ride more sensitive and give a perceived "softer" or probably more appropriately named "plusher" ride. This allows a user to jump up one rate without having the added "harshness" when doing so.

As you stated yes they will have less unsprung mass (although I'm not actually sure if that's right, is 50% the spring considered unsprung?) allowing the suspension to react quicker and just like wheels/rotors and everything else which all drastically help suspension.

As for an old vs new spring the spring on my bike was only one season old and had about 1-2 turns of preload (which in less than 1/16 and in on this shock) and unlike a vehicle there is no load on them without a rider (the rider is the main mass) so as for it being fatigued after only one season and being my dedicated dh bike it only sees about 6-8 trips a season so I highly doubt it was fatigued when I changed to the alloy spring.

As stated though it is a very slight difference but I'll bet the weight savings difference for this size size spring isn't as much as a car spring.