Just got my Powertrix coils in... KTS watch out! - Page 3 - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

chmercer · 10-05-2005, 01:23 PM

Quote:

Originally Posted by BobbyBoy

with the KTS at the same ride height and dampening, my rear tires would rub on the KTS setup

uhh ok wait, you are saying that your tires are rubbing on the actual car? or the coilover? if your tires are rubbing on the car, you need to fix your fenders / change your wheels tires / whatever. fucking up your suspension travel to avoid rubbing your tires is totally shitty. that would be like if my tires rubbed on my car at full compression, and to fix it, i just put an extra bump stop on the shock. totally stupid.

if you are saying that the rear tires are rubbing on the actual spring/shock assembly, this would be because the KTS have a larger O.D. spring than the powertrix (I have no idea if this is the case or not, im just saying that this is like the only thing that could cause rubbing on the suspension)

if you are smoking your tires on the inner fender well why do you not just hammer it out of the way?

If you refuse to actually fix your clearance issues the proper way, a better idea than just trying to crank the shit out of the dampening would be to lower your car about a half inch more than you want (using the lower bracket) and then raise the car back up to the previous height via preloading. this will give you a little more stiffness without altering the ride height. again this is more of a band aid than anything because it sounds like the main problem is your wheels dont fit.

regardless, i will continue to boycott anything powertrix sells, 1. because they tried to sell people control arms with zerk fitting heim joints and call them performance parts and 2. because of this TOTALLY ROCKIN shock dyno graph on the coilover webpage

and 3. because right next to the coilover link, they have the link for the bus, snow mobile, jeep, and tractor shocks.

last thing

Quote:

Lets say if 2 vehicle are at the same ride height, and they have 2 inches of suspension travel until the tires rub. If they both hit a bump and one vehicle rubs the tire on the inner fender and the other car doesn't, that means that the vehicle that rubbed had 2 inches or more of suspension travel, while the other car had less than 2 inches.

this is totally false. unless you are assuming that every variable is exactly the same except for the internals of the shock. are the shocks exactly the same height? same number of threads? springs exactly the same rate? both equally preloaded? same speed, same bump, same load in the car? blah blah blah.

edit - also, flip your brake rotors

HyperTek · 10-05-2005, 01:34 PM

someone should send a set to koni to put on thier shock dyno

BobbyBoy · 10-05-2005, 01:38 PM

Regardless the rubbing, non rubbing issue is moot because it was just an observation I made while driving the car on the SOFTEST dampening setting. The tires rubbed before occasionally on bumps, because I didn't cut high enough on the stock fender. Easy fix when I have the time to do it. I just wanted to get the coilovers on the car for a review. The ride height setting are exactly the same as my KTS (measured with tape measure) as well as the amount of preload.

As for the final example all the variables would be equal even the same bumps and speed except for the struts being different.

edit- The brembo install diagram showed the slot orientation that way.

driftking777 · 01-08-2006, 10:42 PM

hey bobby boy...sorry to bring up an older thread, but wondering what your thinking of the Powertrix still? Worth the money?

McRussellPants · 01-09-2006, 01:40 AM

Quote:

Originally Posted by chmercer

regardless, i will continue to boycott anything powertrix sells, 1. because they tried to sell people control arms with zerk fitting heim joints and call them performance parts and 2. because of this TOTALLY ROCKIN shock dyno graph on the coilover webpage

and 3. because right next to the coilover link, they have the link for the bus, snow mobile, jeep, and tractor shocks.

MFWerd.

TypeXcoupe · 01-19-2006, 04:32 AM

Hey Bobby,

This is old news but I assume your rear camber settings were the same on both suspension systems when they were installed. This would more likely result in the rubbing issue? Maybe you're running more neg camber now in the rear?

And regarding this,

"If you refuse to actually fix your clearance issues the proper way, a better idea than just trying to crank the shit out of the dampening would be to lower your car about a half inch more than you want (using the lower bracket) and then raise the car back up to the previous height via preloading. this will give you a little more stiffness without altering the ride height. again this is more of a band aid than anything because it sounds like the main problem is your wheels dont fit."

I wanted to just make sure that people don't misunderstand this. I'm not tryin to make any enemies here, i'm a newbie too but I been around coilovers for a pretty long time as well. It just seems there is a contradiction in your statement and would simply like it clarified.

You said to lower the vehicle with the lower bracket and then raise it back up by adding preload to the spring, yet it "won't alter the ride height". I see a "raise it back up" and "won't alter the ride height".

But from my experience with these types of coils, you will never ever ever lower the spring so that there is slop in the springs position. Therefore the spring should always be snug and ride height should only be adjusted by the independent lower bracket. Preloading springs I would more suggest for someone who either has a lot of "ass dyno" time, understand the physics behind it, or pays someone to corner balance their car.

In regards to the coilover quality, name brand thing and so forth. I do believe it is a toss up and definitely believe that end users pay more to name brand companies because those companies have expenses to promote the marketting and "race proving" of their product.

However, I think one of the items that many people fail to consider are the small details.

- Material quality, spherical bearings, bushings, etc....

- Spring Quality, any spring dynos out there for these people? While many people believe a linear spring is truly linear, are being misled. A linear spring has much more "linear" properties than a progressive spring. Some linear springs are better than others because they have a constant spring rate over a larger range of compression. Some spring will only reach ideal spring rate after 35% compression and approach "coil binding" properties near 75%, spring rate goes thru the roof. That's only 40% of stroke that retains a constant spring rate. Keep in mind with your car on the ground, you've loaded suspension and probably used up about 15% -20% of your stroke right there on a coilover.

GOOD Springs like ERS, Swift, Zeal X Coils, have a much broader range of linearity. They will reach optimal spring rate at 20% and maintain it upwards of 85% to 90%, yielding about 70% of linear stroke. Since your suspension loaded starts you at about 20% compression these spring rates are much more "accurate" than the aforementioned. So there's money to be found in that technology. I rarely ever see anyone discuss spring dynos. I've taken shitty cheap ass coilovers, put swift springs or Eibach Racing Springs on them and yielded a much less bumpy ride. Might be a cool upgrade for something like this. See if you can buy it without springs and then order some Swift ones.

- Serviceability is very important. Do they overhaul or do full damper replacement. What's the turnaround time for that and the cost of such. I know these coilovers are cheap and you would just buy a whole set, but if under warranty it will be good to know how long your car will be on jackstands.

- Does the company provide legitimate technical data supporting the quality of the Valving. A lot of this can be propoganda also. Was the dyno taken after 15mins or 20mins to check for fatigue as well? Changes in the damping rates over extended time?

- Definitely is it monotube or twin tube, is there a free floating piston to separate the oil and gas to prevent cavitation?

- Do you have the ability to not only choose your own spring rates but also have the valving modified to suit them?

So obviously some of these truly "penske, moton" type services won't be offered and you save a lot of money, but you lose some "flexibility" as well. I just thought i'd spit that out there so people can have a proper judge of value.

Most monotube coils have to be rebuilt in three years anyway. If they're this cheap i'd just buy a new set of dampers/shell casings.

Peace.

Ian · 01-20-2006, 09:01 AM

I have my shocks preloaded to lower my car more (S14's don't go low enough on megan racing...getting new coilovers soon that are coming out...will introduce to Zilvia when I am allowed)

I have no problem w/ the spring being dropped off of the perch

TurDz · 01-20-2006, 03:58 PM

TypeXcoupe, you bring up very good points and I agree with you on spring dynos. Thanks for the insight.

McRussellPants · 01-20-2006, 06:03 PM

Quote:

Originally Posted by mainevent212

I have my shocks preloaded to lower my car more (S14's don't go low enough on megan racing...getting new coilovers soon that are coming out...will introduce to Zilvia when I am allowed)

I have no problem w/ the spring being dropped off of the perch

Uhhmm... if anything preloading raises the car.

I preloaded my KTS on the front and my thinking was - to get the spring out of the way so the lower bracket can go higher. but really the shock just compresses less when you drop it and it ends up being higher. mine went down 1-2cm when I took the preload out.

SoSideways · 01-20-2006, 06:56 PM

Quote:

Originally Posted by McRussellPants

Uhhmm... if anything preloading raises the car.

I preloaded my KTS on the front and my thinking was - to get the spring out of the way so the lower bracket can go higher. but really the shock just compresses less when you drop it and it ends up being higher. mine went down 1-2cm when I took the preload out.

He proloaded the shocks, not the springs.

Basically, if the coilover is in your hands, and not on the car, you would loosen the lower spring purches and move them down, until your spring is no longer seated on the purches, but is free to move around.

That way, when the weight of the car is put on the coilover, the shock compresses, and thus preloads, before the spring even seats. But once the spring seats, the shock stops preloading any more.

That's what you have to do to your coilovers if you want to lower your car more, but cannot do it with the lower bracket anymore.

McRussellPants · 01-20-2006, 07:44 PM

Right... non captive springs commonly refered to as "drooping spring". I've done that on my rear.

SoSideways · 01-20-2006, 10:52 PM

Quote:

Originally Posted by McRussellPants

Right... non captive springs commonly refered to as "drooping spring". I've done that on my rear.

Ok... so... why did you say that it raises your car?

Dousan_PG · 01-20-2006, 10:56 PM

preloading raises
non-captive (loose) is dropping it lower--drooping

he didnt say it.

Quote:

if anything preloading raises the car.

which is correct.

SoSideways · 01-20-2006, 11:03 PM

Ok so I guess we're all on the same page, just worded differently.

I was talking about the shock, not the springs.

What I was talking about, is the same thing:

Droopy springs = lowering car.

McRussellPants · 01-21-2006, 12:12 AM

Exactly, I've never heard anyone say preloading shocks besides motorcycle guys.

I saw preload and mistook shock for spring.

BobbyBoy · 01-21-2006, 12:19 AM

Eh, I've been awol out of state over the holidays and such, just got back home today. First thing I did was take the forty for a spin.

Cant say anything bad about the coilovers still, I have had no issues with them thus far. As far as driving feel, they seem very capable, and comparable to the others I have used in the past, and have experienced in my friends cars as well.

Keep in mind the car is equipped with a lot of other suspension mods, so the ride is very go kart like, turns in very sharp and clean.

As far as springs, I dont know who makes them, but you can order different rates. I am not sure if you can valve the dampeners accoring to the rates, in fact I dont know of any readily available brands that you can.

Serviceability is dont through replacement dampers, same way that the KTS are done. I am not sure of cost, that would be something to ask the Powertrix people about.

Regardless, I am not here to sell parts, just giving out more alternatives. I like the fact that I have inverted monotube setup with lightweight aluminum sheels for a very affordable cost. If no one else has these coils it's very well fine by me since I like having stuff that not many other people have

10-05-2005, 01:34 PM	#62
HyperTek Post Whore! Join Date: Mar 2003 Location: Cali Posts: 13,224 Trader Rating: (3) Feedback Score: 3 reviews	someone should send a set to koni to put on thier shock dyno __________________ Keep it Classy

10-05-2005, 01:38 PM	#63
BobbyBoy Zilvia Junkie Join Date: Nov 2003 Location: San Jose CA Age: 40 Posts: 433 Trader Rating: (0) Feedback Score: 0 reviews	Regardless the rubbing, non rubbing issue is moot because it was just an observation I made while driving the car on the SOFTEST dampening setting. The tires rubbed before occasionally on bumps, because I didn't cut high enough on the stock fender. Easy fix when I have the time to do it. I just wanted to get the coilovers on the car for a review. The ride height setting are exactly the same as my KTS (measured with tape measure) as well as the amount of preload. As for the final example all the variables would be equal even the same bumps and speed except for the struts being different. edit- The brembo install diagram showed the slot orientation that way. __________________

01-20-2006, 03:58 PM	#68
TurDz Nissanaholic! Join Date: May 2003 Location: Bay Area, CA Posts: 1,618 Trader Rating: (0) Feedback Score: 0 reviews	TypeXcoupe, you bring up very good points and I agree with you on spring dynos. Thanks for the insight. __________________

01-21-2006, 12:19 AM	#76
BobbyBoy Zilvia Junkie Join Date: Nov 2003 Location: San Jose CA Age: 40 Posts: 433 Trader Rating: (0) Feedback Score: 0 reviews	Eh, I've been awol out of state over the holidays and such, just got back home today. First thing I did was take the forty for a spin. Cant say anything bad about the coilovers still, I have had no issues with them thus far. As far as driving feel, they seem very capable, and comparable to the others I have used in the past, and have experienced in my friends cars as well. Keep in mind the car is equipped with a lot of other suspension mods, so the ride is very go kart like, turns in very sharp and clean. As far as springs, I dont know who makes them, but you can order different rates. I am not sure if you can valve the dampeners accoring to the rates, in fact I dont know of any readily available brands that you can. Serviceability is dont through replacement dampers, same way that the KTS are done. I am not sure of cost, that would be something to ask the Powertrix people about. Regardless, I am not here to sell parts, just giving out more alternatives. I like the fact that I have inverted monotube setup with lightweight aluminum sheels for a very affordable cost. If no one else has these coils it's very well fine by me since I like having stuff that not many other people have __________________

01-08-2006, 10:42 PM	#64
driftking777 Zilvia Junkie Join Date: Feb 2005 Location: South Dakota Posts: 554 Trader Rating: (2) Feedback Score: 2 reviews	hey bobby boy...sorry to bring up an older thread, but wondering what your thinking of the Powertrix still? Worth the money?

01-19-2006, 04:32 AM	#66
TypeXcoupe Join Date: Oct 2005 Location: RightSIDE Posts: 25 Trader Rating: (0) Feedback Score: 0 reviews	Hey Bobby, This is old news but I assume your rear camber settings were the same on both suspension systems when they were installed. This would more likely result in the rubbing issue? Maybe you're running more neg camber now in the rear? And regarding this, "If you refuse to actually fix your clearance issues the proper way, a better idea than just trying to crank the shit out of the dampening would be to lower your car about a half inch more than you want (using the lower bracket) and then raise the car back up to the previous height via preloading. this will give you a little more stiffness without altering the ride height. again this is more of a band aid than anything because it sounds like the main problem is your wheels dont fit." I wanted to just make sure that people don't misunderstand this. I'm not tryin to make any enemies here, i'm a newbie too but I been around coilovers for a pretty long time as well. It just seems there is a contradiction in your statement and would simply like it clarified. You said to lower the vehicle with the lower bracket and then raise it back up by adding preload to the spring, yet it "won't alter the ride height". I see a "raise it back up" and "won't alter the ride height". But from my experience with these types of coils, you will never ever ever lower the spring so that there is slop in the springs position. Therefore the spring should always be snug and ride height should only be adjusted by the independent lower bracket. Preloading springs I would more suggest for someone who either has a lot of "ass dyno" time, understand the physics behind it, or pays someone to corner balance their car. In regards to the coilover quality, name brand thing and so forth. I do believe it is a toss up and definitely believe that end users pay more to name brand companies because those companies have expenses to promote the marketting and "race proving" of their product. However, I think one of the items that many people fail to consider are the small details. - Material quality, spherical bearings, bushings, etc.... - Spring Quality, any spring dynos out there for these people? While many people believe a linear spring is truly linear, are being misled. A linear spring has much more "linear" properties than a progressive spring. Some linear springs are better than others because they have a constant spring rate over a larger range of compression. Some spring will only reach ideal spring rate after 35% compression and approach "coil binding" properties near 75%, spring rate goes thru the roof. That's only 40% of stroke that retains a constant spring rate. Keep in mind with your car on the ground, you've loaded suspension and probably used up about 15% -20% of your stroke right there on a coilover. GOOD Springs like ERS, Swift, Zeal X Coils, have a much broader range of linearity. They will reach optimal spring rate at 20% and maintain it upwards of 85% to 90%, yielding about 70% of linear stroke. Since your suspension loaded starts you at about 20% compression these spring rates are much more "accurate" than the aforementioned. So there's money to be found in that technology. I rarely ever see anyone discuss spring dynos. I've taken shitty cheap ass coilovers, put swift springs or Eibach Racing Springs on them and yielded a much less bumpy ride. Might be a cool upgrade for something like this. See if you can buy it without springs and then order some Swift ones. - Serviceability is very important. Do they overhaul or do full damper replacement. What's the turnaround time for that and the cost of such. I know these coilovers are cheap and you would just buy a whole set, but if under warranty it will be good to know how long your car will be on jackstands. - Does the company provide legitimate technical data supporting the quality of the Valving. A lot of this can be propoganda also. Was the dyno taken after 15mins or 20mins to check for fatigue as well? Changes in the damping rates over extended time? - Definitely is it monotube or twin tube, is there a free floating piston to separate the oil and gas to prevent cavitation? - Do you have the ability to not only choose your own spring rates but also have the valving modified to suit them? So obviously some of these truly "penske, moton" type services won't be offered and you save a lot of money, but you lose some "flexibility" as well. I just thought i'd spit that out there so people can have a proper judge of value. Most monotube coils have to be rebuilt in three years anyway. If they're this cheap i'd just buy a new set of dampers/shell casings. Peace.

01-20-2006, 07:44 PM	#71
McRussellPants Nissanaholic! Join Date: Oct 2005 Location: Austin, Tx Posts: 2,168 Trader Rating: (0) Feedback Score: 0 reviews	Right... non captive springs commonly refered to as "drooping spring". I've done that on my rear.

01-20-2006, 11:03 PM	#74
SoSideways Post Whore! Join Date: Apr 2003 Location: 你老母 Posts: 4,371 Trader Rating: (4) Feedback Score: 4 reviews	Ok so I guess we're all on the same page, just worded differently. I was talking about the shock, not the springs. What I was talking about, is the same thing: Droopy springs = lowering car.

01-21-2006, 12:12 AM	#75
McRussellPants Nissanaholic! Join Date: Oct 2005 Location: Austin, Tx Posts: 2,168 Trader Rating: (0) Feedback Score: 0 reviews	Exactly, I've never heard anyone say preloading shocks besides motorcycle guys. I saw preload and mistook shock for spring.