ZPS Build Thread
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Just to let everyone know I bought the factory manual off of ebay and it is what it says. $13 or so shipped.
https://www.ebay.com (commissions earned)
https://www.ebay.com (commissions earned)
ok so I got some more good information with pictures. I know I am boring just talking all of the time without pictures. So I got the RE-11A's mounted on the car and the wheels are back to silver for now. Damn these tires have a lot of grip. I am really looking forward tot he autocross nest weekend with them. Then the wheels will be painted white.
So I decided to look into strut bar stuff for our car. I started to look into the rear since molex7 started a thread asking about them. Now before I go on, I want to say that by no means is what I did the end all of if strut braces are needed or not. These are just somethings I did to see if the chassis flexes and how much. Not saying that they are truly accurate, but they make sense to me. If you guys have any further thoughts on how I did it let me know I would love to hear them. So first I needed a way to get the rear to be loaded. So I put one of my extra wheels under one of the rear tires like so.
I figure that since the other rear tires is up in the air that this would be as much weight transfer I could get in the rear. I then noticed like molex7 mentioned that the rear hatch closed and opened differently. It had to center itself on the latch before it would close. So time to measure. I put 4 pieces of tape on the weather stripping of the rear hatch. I tried to get them to be the same length when you measure the X that they create. Basically I wanted to set them so the rear of the car was "square" Then I could measure the change. Here is a picture of where I put the tape.
So with the car sitting flat when you measure from the top right to bottom left I got 43 3/4" and the same from the top left to the bottom right. I then put the rear tire back under the wheel and measured again. From the top right to the bottom left it was 43 5/8" and from the top left to the bottom right it was 43 7/8" So one moved out 1/8" and the other moved in 1/8" which makes sense since the rear hatch area is just parallelograming (when a square falls over into a diamond shape). Now I did repeat these measurements twice to make sure they were accurate and I was getting the same thing both times.
So thinking where a rear strut brace might be, I measured from the mounts where the rear seats snap into place. Seemed like a solid location which you could bolt to. Loaded and unloaded like above they both measured the same distance apart, 44 1/8" so the distance between them did not change so your typical strut bar with ball joints on the end would not help since the distance did not change. A bar that had solid mounts might help to stiffen it, but I could not come up with a good way to measure the change in the angle of that mounting point. I could use an angle gauge, but I don't have one at the house.
Now moving to the front I measure from one of the top hat mounting bolts on the chassis to the other on the other side.
On the ground it measured 39 13/16" on the dot. I then jacked up the rear of the car a lot to make the front roll. I measured the roll by the distance between the ground and the top of the fender on each side. The difference was 4 1/4" which was as much travel as I have in the front of the bilsteins so yea it was a lot.
I then measured the bolts again and I got the exact same number so it looks like a front strut bar won't really help out at all from what I can see. Not surprised since the top hats are so close to the firewall, but Mini's are the same way and a strut bar helps them a lot. Then again I couldn't measure the angle of the top hats to see if maybe the angle of the tops changes with respect to each other, but I don't really see that as how the chassis would shift in the front.
Thoughts anyone?
So I decided to look into strut bar stuff for our car. I started to look into the rear since molex7 started a thread asking about them. Now before I go on, I want to say that by no means is what I did the end all of if strut braces are needed or not. These are just somethings I did to see if the chassis flexes and how much. Not saying that they are truly accurate, but they make sense to me. If you guys have any further thoughts on how I did it let me know I would love to hear them. So first I needed a way to get the rear to be loaded. So I put one of my extra wheels under one of the rear tires like so.
I figure that since the other rear tires is up in the air that this would be as much weight transfer I could get in the rear. I then noticed like molex7 mentioned that the rear hatch closed and opened differently. It had to center itself on the latch before it would close. So time to measure. I put 4 pieces of tape on the weather stripping of the rear hatch. I tried to get them to be the same length when you measure the X that they create. Basically I wanted to set them so the rear of the car was "square" Then I could measure the change. Here is a picture of where I put the tape.
So with the car sitting flat when you measure from the top right to bottom left I got 43 3/4" and the same from the top left to the bottom right. I then put the rear tire back under the wheel and measured again. From the top right to the bottom left it was 43 5/8" and from the top left to the bottom right it was 43 7/8" So one moved out 1/8" and the other moved in 1/8" which makes sense since the rear hatch area is just parallelograming (when a square falls over into a diamond shape). Now I did repeat these measurements twice to make sure they were accurate and I was getting the same thing both times.
So thinking where a rear strut brace might be, I measured from the mounts where the rear seats snap into place. Seemed like a solid location which you could bolt to. Loaded and unloaded like above they both measured the same distance apart, 44 1/8" so the distance between them did not change so your typical strut bar with ball joints on the end would not help since the distance did not change. A bar that had solid mounts might help to stiffen it, but I could not come up with a good way to measure the change in the angle of that mounting point. I could use an angle gauge, but I don't have one at the house.
Now moving to the front I measure from one of the top hat mounting bolts on the chassis to the other on the other side.
On the ground it measured 39 13/16" on the dot. I then jacked up the rear of the car a lot to make the front roll. I measured the roll by the distance between the ground and the top of the fender on each side. The difference was 4 1/4" which was as much travel as I have in the front of the bilsteins so yea it was a lot.
I then measured the bolts again and I got the exact same number so it looks like a front strut bar won't really help out at all from what I can see. Not surprised since the top hats are so close to the firewall, but Mini's are the same way and a strut bar helps them a lot. Then again I couldn't measure the angle of the top hats to see if maybe the angle of the tops changes with respect to each other, but I don't really see that as how the chassis would shift in the front.
Thoughts anyone?
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first off great research with good pictures! From looking at what you did my hypothesis as to why you didn't see much flex is because you are measuring from the strongest points. Even then i don't think you would see much measurable flex in this kind of a scenario, but in say autocross where there is rapid and constant change of force being applied it might be a different story. I think you're spot on with the front strut bar, Andy Hollis has mentioned that for our cars it's not vital and most b-spec cars do not run them, i have one on my car and the change was minimal. You can feel it, but it's definitely not going to be the deciding factor of a win or a loss. The front being designed as it is with the struts so close to the firewall definitely keeps everything strong around there, but the rear just seems too open. The only thing the rear has in terms of cross strength is the roof, which doesn't seem amazingly strong (but I've never rolled the car!), and the subframe. If there was strengthening that would be beneficial i would think it would be in the rear. Having zero flex at all at the strut points in the rear is a alarming though, I'm surprised with how much the body flexes that the chassis doesn't seem to budge much at all.
extremez31
Member
- :
- 2013 Mazda2 Sport (5 Speed)
I have the tripoint bar in my car, Definitely helps the car rotate but, itll put a huge dent in your rear muffler and EVAP box, my car is about 3/4" lower than stock. The tripont was made for bspec and the kit eliminates the muffler. I opted for a side exit exhaust and only on extreme bumps does it hit the EVAP box. im going to lower the car an inch in the next 2-3 weeks well see how it all holds together.
extremez31
Member
- :
- 2013 Mazda2 Sport (5 Speed)
Right now I have the fiesta B-spec kit with 600LB front springs and 350LB rear
My buddy has the bilstein off the shelf kit with Eibach 450's up front and the Bilstein kit rear springs. We swap cars at Autox and my times are identical in both cars usually 1-2 10'ths. He sees the same results when he drives although my cars easier to drive at the limit.
1/4 total Toe out can be achieved by cranking Tripoint bar 100%. measured on an alignment rack. I am running 1/16 out each side 1/8 total
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Yea so you have stiffer rear springs as well so mine would definitely hit stuff if I got the tripoint. I will just plan to at least make the axle back part of the exhaust before I get the rear bar.
I just want to get to 0 toe in the rear. the 1/4" of toe in I am pretty sure is what is making the car not rotate like I want in the tighter turns. It would be great as it sits on a track though. That is why I really like the tripoint. I can easily and quickly adjust it.
I just want to get to 0 toe in the rear. the 1/4" of toe in I am pretty sure is what is making the car not rotate like I want in the tighter turns. It would be great as it sits on a track though. That is why I really like the tripoint. I can easily and quickly adjust it.
With the Tri point bar, you can get that much toe out also. Need to crank in 2 turns, but plenty of rotation, do much in fact, we were lowering rear tire pressures to get better transient response in slaloms.
After running the bar for almost 2 months, I backed it off to zero and had really close to zero toe in the rear. it's as if the bar re-arched the beam, or stretched it a bit. But yes, it's does make a HUGE dent in the muffler. Mine has clearances itself by now, but has destroyed any resale value in it.
Extremes car without the bar would not rotate, but we could get in to hop around corners with the 225 Rivals. Last weekend, you could drive the hell out of it, much like a 4gen Civic. you can pitch it, toss it and let it move in the corners.
Noise from clearance issues aside, the bar works very well.
Noise from clearance issues aside, the bar works very well.
It will still hit the evap box shield. not hard enough to break anything, but does dent it quite a bit. Enough to peel the paint off the bar. Mine will get a respray this winter.
How low is your car though? Mine is pretty high so I don't think I will hit the evap stuff that hard if at all. I don't know why you even went to the point of having toe out in the rear. That is just a bit much to try to help get rotation. Just going to 0 toe will work wonders for mine. Then again I just looked above and I am guessing you are the one who has the 450F with the stock bilstein rears. That is a lot of front spring compared to the rear. If anything on mine I might do 400F 300R, or there about. I won't change springs until I get the shocks revalved though.
extremez31
Member
- :
- 2013 Mazda2 Sport (5 Speed)
From what I understand about our rear is, Toe is dynamic. The more load we put on the rear end the more the car toe's in. So Jasyats is running 230LB rear springs and sits lower than I do, you can squeeze 2 fingers in his wheel wells. approx 1.25" gap there.
My car sits 3/4" higher than him, I have approx 2.00" gap in my rear well with 350LB springs. I daily drive and my bar hits the EVAP box on highway dips. My bar currently sits 1.7" under the EVAP box which equates to requiring approx 608LBS of additional rear load before they kiss.
I have exactly 1/16" out on the rear Left and 3/32 out on the rear right. If what I've read about our cars is in fact correct then I'm somewhere closer to 0 toe under extreme load.
"The rear suspension's twist beam is specifically tuned for stability, given the short 98.0-in. wheelbase of the car, so that under load the outside rear wheel will toe-in slightly, which helps keep the car controllable in transitions at speed. This showed through our slalom test with an impressive run of 67.8 mph!"
Read More.
http://www.roadandtrack.com/car-reviews/car-comparison-tests/ford-fiesta-vs-mazda2
My car sits 3/4" higher than him, I have approx 2.00" gap in my rear well with 350LB springs. I daily drive and my bar hits the EVAP box on highway dips. My bar currently sits 1.7" under the EVAP box which equates to requiring approx 608LBS of additional rear load before they kiss.
I have exactly 1/16" out on the rear Left and 3/32 out on the rear right. If what I've read about our cars is in fact correct then I'm somewhere closer to 0 toe under extreme load.
"The rear suspension's twist beam is specifically tuned for stability, given the short 98.0-in. wheelbase of the car, so that under load the outside rear wheel will toe-in slightly, which helps keep the car controllable in transitions at speed. This showed through our slalom test with an impressive run of 67.8 mph!"
Read More.
http://www.roadandtrack.com/car-reviews/car-comparison-tests/ford-fiesta-vs-mazda2
Well that would be easy enough to look at. I will check the rear toe of the car, then jack the rear up and weigh it down to get the range of toe as the entire car moves up and down. I might be able to look into that a little tonight while at my friends shop. While under hard cornering the loading would be different, but then again only 1 wheel would be on the ground actually doing anything so it would probably be about the same.
I wouldn't be surprised if it is correct. Most cars just have a bunch of camber gain in the rear to help with stability, but with ours not changing much at all they might do it with toe.
I wouldn't be surprised if it is correct. Most cars just have a bunch of camber gain in the rear to help with stability, but with ours not changing much at all they might do it with toe.
ok so while at the shop today I did get a chance to look at the change in toe with the ride height of the car. My car is 23 7/8" in the rear from the ground to the top of the fender and it has 1/4" of total toe in. I then raised it up to 26 3/4 and saw 1/8 of toe in. I then loaded the car up with stuff and got it down to 23" and it went up to 9/16 of toe in so yea the rear end definitely toe's in as the rear lowered so under cornering loads it will be more toes in. From while video taping my rear suspension mine looks to compress to about 1" while cornering so the numbers seem pretty good there. It all just re enforces the point that it seems like getting the toe in out of our rear suspension would be a good thing.
The thought process was that the Tri point bar not only would give more static toe out, but also improve the rear combined rate. As you found out, the more the rear is loaded, the more toe (in) increases. Starting with a dramatic number at the rear (out) was an experiment to see how loose we could get the car. Did help get the car to dance through the slaloms, turn in improved, but wheel spin is still an issue, mid corner and corner exit. Car was much more manageable in the corners.
Extremez bar is at 1.5 turns, mine was measured at 2 turns.
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That is correct that the tri point bar will increase the roll rate so the rear won't move as much, but that is just doing the same thing as a rear sway bar. That is a different thing, but with similar results. Plus the increase in roll rate doesn't mean much once you get the car loaded up so the inside is in the air. Can't transfer any more weight no matter how stiff you are. At that point the outside rear tire is just steering the car from the rear in whatever direction it is pointing and what ever slip angle your tires are running at.
This weekend I am going to test this out at our autocross in the 2 by doing 2 runs with the rear pressure high like I usually have it(45ish), then do 2 runs with it low (30psi) I am hoping that the increase in slip angle will simulate having less toe in on the car.
This weekend I am going to test this out at our autocross in the 2 by doing 2 runs with the rear pressure high like I usually have it(45ish), then do 2 runs with it low (30psi) I am hoping that the increase in slip angle will simulate having less toe in on the car.
extremez31
Member
- :
- 2013 Mazda2 Sport (5 Speed)
What I think you'll find is the rear will start to hop around corners as mine did with rear pressures under 38 psi. We didn't go any faster but the car was more consistent after disconnecting the front sway bar. Run times were equal.
With they sway bar disconnected front spin was reduced but still present and the rear inside wheel started to lift. I am going to experiment with increasing rear springs to 600 from 350 to see if the rear inside will stay planted.
