4wd4me

this was from way back in your thread but I was wondering how that worked out for you? were you able to get the extra caster you were looking for? about how much? I was thinking of doing the reverse (to get the strut more vertical then add it back with the plate), but don't want to lose any measurable amount of caster...

Butt Dyno

iTrader: (10)

It didn't really affect the caster numbers at all. From my notes, they were +4.9/+5.1 afterwards. I guess you have to do something like the PSRS to get into the +6 territory.

Butt Dyno

iTrader: (10)

Silly season... not much going on. The car in its hibernative state:



Life support...


The shocks are back!



Bearings are on - bottom of the spring (have to look close) - can’t wait to not have the spring bind anymore.


The shocks were at Performance Shock Inc, in Sonoma California. I asked for “before” dynos, the double digressive pistons, a matching revalve, and a general service (o-rings, etc). It only took PSI a week to turn them around which is a nice bonus.

They did a great job packaging them, cleaned em up all nice, and they even replaced the slightly melted Moton stickers on the front canisters (the ones that spend all their time in a hot engine bay). That was a nice bonus. They sent me PDFs of the dynos, but when I asked for the raw data so I could plot it in Excel or whatever, they sent me the PVP files and said that all I needed to plot them was the freely available Roehrig “Shock” software (available here) to plot them. That stuff isn’t very well packaged software wise, and seems to take forever to install, but it works!

PSI sent me back ten dyno files:
before:
* rear, full soft
* rear, full hard
* front, full soft
* front, full hard
After:
* left rear, full soft
* left rear, middle
* right rear, middle
* left front, middle
* right front, middle
* left rear, full hard

Theoretically there are 24 different combinations of this (4 assemblies, before/after, 3 settings) but this is enough for me and definitely demonstrates that the new pistons are having the desired effect. The before/after dynos are pretty much what I expected. These were all done with the nitrogen at 160 psi - might run a little higher, maybe a little lower, but that seemed like a decent normal number.

Again, for reference, here’s the advertised curves, on a Mustang:


Now the pictures of mine. Keep in mind that the scales vary a little between the graphs depending on what’s plotted. Please ignore the double entendres It’s inevitable.

Here are the four “before” graphs front/rear, soft/hard. At 2 in/sec, the difference between soft and hard is about 150 lbs.


Here’s the before/after on full soft. (orange = after; other two = before) The difference here is pretty subtle but you can still see it is more digressive than before.


Here’s the before/after on full hard. (blue = after; other two = before). You can really see the curve difference here.


Here’s the left rear: soft, middle, hard. Really shows how much low speed adjustability there is. At 2 in/sec the difference between soft and hard is about 300 lbs - double the difference from the “before” graph.



Here’s all four on the middle settings, showing that they are matched:



On paper, I am definitely psyched. The curves look great. I'm hoping that my "holy grail" goals of better ride quality/handling of imperfections and wider adjustment range come true. I'm going to try to drive the car a few more times on the Bilstein+Swift setup just to get a baseline and probably get them installed in a couple weeks-ish so it's ready by the start of March and the first few events.

Hopefully we can get decent enough weather that I can bring the car out at some point. There's a ton of salt on the roads right now so the Saab has been doing all the work. The car has not even been started in 2013 yet... gotta fix that

FilthyEvo

iTrader: (3)

Nice! Bet you can't wait to get those back in and get a test run!

Construct

iTrader: (4)

These sound awesome. Any updates on this?

Butt Dyno

iTrader: (10)

Glad you bumped this. I just emailed him asking

Headed up to CBRD to get the Motonz back on the car on Monday... definitely excited! Their new shop looks amazing.

03threefiftyz

Make sure they set the shocks to fast on install. They are motons....it is just that easy.

Butt Dyno

iTrader: (10)

So, question for the audience - if you had unfettered access to a set of scales for a couple days, what would you do?

I'm going to get the ride height set about right, and then get it on scales to see about the corner weights, as well as just seeing the overall weight - but are there any other datapoints that would be useful?

Butt Dyno

iTrader: (10)

CBRD trip for the suspension install!

CBRD's shop was already spotless and clean, but then they decided to make it 4 times bigger.

https://www.evolutionm.net/forums/ev...neak-peak.html

Some pictures off my camera, not quite as nice...






Today was my first visit. It's not 100% done yet but has all the key features, including Chad and his crew. For eye candy, there are some pretty excellent cars in the climate controlled storage area, including 1995 BMW M3 LTW #4.

Despite taking excruciating notes and pictures doing the un-install of the suspension, I really wanted to have them re-install it. I figured if I missed a zip tie or something I didn't want a hose getting clipped and then having to send stuff back to California. Plus they keep things like nitrogen on hand, and if you screw up and forget your aftermarket rear shock bolts (hypothetically) they probably have some

Other than that, it was drama-free. All back to normal!


I need to double check the ride heights, and I'm going to try to weigh the car this week just to figure out how much weight I've dropped versus early 2011 when I first weighed it. Flashback:
So since then I've added seats (guessing -20), lightweight front rotors (-8) the power mods (no clue), and a lightweight battery (maybe -20). Can I crack 3100? Hope so. It does have the 6 speed which isn't helping.

After that, to Andrewtech for an alignment.

New pistons + valving, first impressions

I didn't have a lot of seat time on the Bilsteins + Swift Spec R springs, but I generally didn't think it rode super well. Daily driveable sure, but I'd probably opt for the Sports if I was doing it again (unless I was going to autox or track the car in that configuration). It definitely got away from the clean Euro ride the car had when it was on the stock springs.

I didn't think the Clubsports were that bad, a little better than my old WRX on similar rates with single adjustable Konis. But between wanting more low speed adjustment and wanting to have the car ride a little better I opted for the new double digressive pistons to get digressive rebound too.

So far I am pretty impressed. Obviously it's hard to make absolute statements about ride quality, and there isn't an objective test for it. But I have a test I like to do to get a relative impression, the stereo test. The stereo test is simple - drive down the highway and see how hard it is to play with the buttons on the stereo. If your hand is skipping around because the car is bouncing, it's pretty hard, but if the bumps are being absorbed it's pretty easy. With the shocks set soft, the new pistons are demonstrably better than the old ones. There's no hiding that you're on three times the spring rate but it handles even the harsh stuff pretty well. There are a couple particularly crummy spots on 495 that I know pretty well (from trying to avoid them on the way back from Fedex) and it's noticeably better there.

The real test is how the car handles with a good alignment and driven in anger, but it's off to a good start. About three weeks to go before the first event.

Tires

So, it seems pretty clear that the Dunlop ZII has relegated the ZIs to the dustbin. In addition to Tire Rack's test, there is some anecdotal evidence on NASIOC that people who switched have picked up a lot of time compared to where they were in 2012. I've already sold my local set and listed my Nationals set as well (only 3 events if anyone wants some for schools or testing or HPDE or whatever). I'm going to try to pick up a set of ZIIs before event #1, I think.

Hopefully the Rivals won't meet the availability deadlines

Butt Dyno

iTrader: (10)

Getting the car on some scales

I last weighed my car in ~April 2011. It was 3172 at the time with about 1/8 a tank of gas, coilovers, stock BBS with RE11s, and a battery that was heavier than stock. I've read all the STU threads and remember some of the folks with RS's getting into the 29xx's. I wasn't willing to go without ABS, which ruled out the RS. My #1 option would have been an SE, as the aluminum roof *and* ABS. But SE's are hard to find, so I ended up with an MR "SE" (MR+appearance package). Near as I can figure, the MR-SE is an SE but with the Bilsteins, the vortex generators, and the 6-speed. From what I've read (might even be linked in here someplace) the 6-speed is about 15 lbs heavier than the 5-speed. If I was ever concerned with weight, I could do a stock-legal package conversion of the car to become an SE - swap the 5 speed, remove the VG’s, switch badges, and have everything else. I’m not likely to do this unless the 6-speed dies but it’s something in the back of my mind.

Now that the suspension’s back on the car, I wanted to take a crack at weighing it and possibly corner balancing it before getting it aligned. The goal was not to be a total slave to the corner weights, since it’s an Evo and it’ll never be balanced “right”, but just to see if I could get it to not be terribly off. I managed to find a friend willing to let me borrow his scales for a little while. I figured I’d document this for anyone reading this in internet land who wants to give this a go themselves. The following caveat applies: I have no idea what I’m doing and you should not impersonate this because awful things could happen. I did the best I could do based on the research I did, but I had never done this before and make no claims about accuracy. If you have suggestions, please offer them. I am capable of learning

One really obvious one is that I don’t have adjustable endlinks. From what I’ve read, on EvoM and elsewhere, in that case you should just leave the endlinks connected.
https://www.evolutionm.net/forums/ev...k-endlink.html
Some other links I found really helpful:

Corner balance guide in general, from Longacre
http://www.longacreracing.com/articles/art.asp?ARTID=1

Rob’s S2000 corner balance
http://robrobinette.com/corner_weight.htm

A thread on LotusTalk about DIY corner balancing. This one was incredibly useful since it was pretty much the same equipment I borrowed:
http://www.lotustalk.com/forums/f91/...ustment-77759/

That equipment was all from Longacre:
* 4 scales
* 4 leveling pads
* The main number box thing
* A “laser” leveling set (not the magic auto-leveling kind but still plenty useful)
* A stand to put the number box on so it was easier to see from the driver’s seat

The overall flow:
* Get the car race-prepped - fuel level, basic guess at ride height, same wheels you race on, etc
* Mark roughly where the wheels are on your floor with tape.
* Get your car out of the way so that you can do the leveling (otherwise the car will block the “laser”)
* Set up the “laser” on its level surface.
* Using the “laser”, set up the leveling pads and make them level.
* Plug stuff in, make sure everything works, and zero out the scales.
* Move the scales out of the way. Move the car in.
* Lift the car onto the pads, and roll it onto the scales.
* Jiggle the car a bunch of times to get as much of the bind as possible out of the suspension.
* Measure. Check weights.
* If you need to adjust, roll the car back off the scales to the back part of the pad, make the adjustment, and then roll the car forward and do the jiggle again.

The first thing I did was set up the “laser”. It took me a couple minutes to figure out, but the easiest way seems to be to align it on the two-post side first


… and then adjust the one-post side until it’s level in every direction.


Longacre does make one of these that automatically levels itself, if you are in the market for this sort of thing. One mistake I made was that it wasn’t in the middle of the 4 pads - I didn’t see that in the instructions until afterwards. Still, it was level (according to the bubble) everywhere so that should be okay.

The next step, and by far the most work, was to create a level surface with the pads. The laser level kit comes with four of these:


You put them on the scales (making sure that the feet never go into the 4 indents) and then aim the “laser” at a certain height. Then you go around to each of the 4 leveling pads, raising and lowering it as necessary in order to get all 4 on the same level.


The garage is sloped a bit in my townhouse. I didn’t realize how bad it was until doing this. I had gotten 3 of the pads fully level and all at the same height and was feeling good. Then I got to the front left and realized that the slope of my garage was so bad that I needed to almost start over. See, the rear right pad looked like this when it was level:


Note the difference between the front side and the back side. The back screw was pretty much at the end of its adjustment range. Meanwhile, the front pads were pretty much at the OTHER end of their adjustment range.


So I needed to pick a common height that would work for both sets of pads. This involved a lot of tweaking and cursing but I eventually ended up at 2 and ⅞” all around.

After getting the heights set, I tightened the locking nuts


And then hooked up the scales in order to zero them out. I hopped on each pad individually and they all weighed me at either 170 or 171 (wearing a very heavy sweatshirt ) After that, I slid the pads out of the way to pull the car in.


You have to be somewhat agile to work in a 1 car garage with all this stuff in it. There is not a lot of room on the sides.


Then put the car up on the pads, one scale at a time.


I had my first weight! 3113 lbs. For clarity, this is with the fuel light having just come in (about a mile ago), my normal stuff in the center console, no floormats, and the TRM wheels instead of the lighter SSR Type C RS’s. Then I realized I should have switched wheels while the car was still on the ground. Doh!

OK, after clearing out the center console and putting the SSR’s on, I was down to 3085 total (LF: 951 ; RF: 980 ; LR: 594 ; RR: 561) and a cross weight percentage of 51%. Not bad for eyeballing the heights. Then I remembered I hadn’t jiggled the car yet. Shaking/bouncing the car didn’t change the weight (as you’d expect) but it did change the percentages:


.3% better with just shoving the car a bunch? Not bad!

Then I remembered that the car wouldn’t be very effective for autocross without a driver. So I hopped in the seat to see how bad it was with me at the wheel. The total went to 3259. And the cross percentage went to 50.5%. I hopped out, flipped out the driver’s side mirror (I folded it in so I could get more left in the garage), jiggled/bounced the suspension again, and got back in the driver’s seat. I ended up with this:


50.3%. It would fluctuate to 50.4% if I held my arm out the window, so I decided to call this good enough rather than try to chase down those last three tenths and risk making it worse.


All that setup just to find out that the corner weights were good enough already. Ah well, it was still pretty interesting.

In terms of how much lighter the car can get...
* I could delete the spoiler. 7 lbs? I am loath to do this... 7 lbs at the back end of the car doesn’t seem like a big deal and I’m kind of a rally car guy at heart.
* I could do rear two piece rotors. ~7 lbs total.
* I could go even lighter on the battery. Mine’s about 15 lbs. Frontish on the car. Have seen some stupid light ones, but let’s use a remotely rational one and say there are 9 lbs to be lost here.
* Lighter catback. Low and at the end of the car, but it’s weight. I have a Perrin stealthish thing now that blows in the low 90s at National events so I could go turndown and still probably be fine. Catback is 27 lbs according to Perrin. More lightweight exhaust discussion here.
* Hollow swaybars maybe. But they’d have to be roughly the same stiffness so I don’t have to set the car up again. I’m not sure what exists here, especially in the front. There’s always cu$tom.
After that... 5 speed swap maybe (~15 lbs).

7 + 7 + 9 + 20 (turndown) + 5 (bars) + 15 (5 speed) would mean -63 lbs, theoretically landing the car at 3022 or so, with SSRs, and the fuel light barely on. But we are definitely into the diminishing returns realm. I am going to do the rotors for sure (rotating mass) but the rest of the stuff is questionable.


After all that was done, I went to Andrewtech for an alignment. No real changes here: -3.5, -1.5, 0 toe. I’m still very happy with how the new setup rides.

Next up is a set of ZIIs. First event is coming up! I'm kind of disappointed that the Rivals were deemed legal until 4-30, since a) the 245-40-17 isn't out yet, b) the tire is not yet available in 4 diameters and six sizes, and c) there are a bunch of national events before 4-30. That said, I am betting the ZIIs and the Rivals will be really close. The hype machine behind the Rivals was pretty powerful. They had a chance to let people test them against the Z1s, but chose to instead test them against the RS3 and R1R. That's telling, IMHO. But we'll see

BriK

iTrader: (11)

Long time listener, first time poster in this thread. I've trolled this thread for a while but now I have even greater interest now that I'm redoing and undoing some mods I did on a whim-- little mods which propelled me right into ASP-- to prep for STU.

Anyway, I had a custom aluminum catback made which napkin math indicates weighs about 5 pounds when "optimized." It runs two mufflers in the midpipe, then has a v-band just behind the rear axle so I can quickly connect or disconnect a third muffler for daily driving. For daily driving with three mufflers, it should still only weigh about 17 pounds. For autocross events, I remove the axle-back, shave 12 pounds, and still have two mufflers (and soon a high-flow cat) to muffle the noise. I did a lot of research and shopping to locate all the parts so I'm happy to share them if you like.

As for lightweight sway bars, it's my understanding the Tanabe 26mm front bar is hollow and shaves about 3 pounds over stock, while the Hotchkis 24mm rear sway bar is also hollow but I'm not sure of weight savings for it.

I've found that Baer Eradispeed 2-piece rotors are the lightest and that eBay has the cheapest prices for them.

As for batteries, the Deka ETX14L is often said to be the same as the Braille 14115; both weigh 11.5 pounds and the Braille is rated at 360 CCA which should be suitable for daily driving, especially in warmer temps. The Deka only costs about $75; not a great price/ pound ratio but could be worth considering.

I'm rambling, but I hope I've helped a bit. Thanks for being so open with your setup and your approach.

RJones

iTrader: (5)

On the lightweight battery front, the Shorai lithium ion ones are worth a look. Huge weight savings and don't cost a fortune.

2.19lb - 270CCA
3.92lb - 360CCA
4.19lb - 405CCA
4.97lb - 540CCA

BriK

iTrader: (11)

I looked at Lithium Ion batteries and the deal killer for me was no ability to jump them, a big downside when living in a cold climate.

Construct

iTrader: (4)

If your Lithium Ion or LiFePO4 battery pack gets drained far enough to require a jump start, you've probably damaged it anyway. Unless it has a proper battery management system that cuts it off, which is not true for the cheap ones I've seen. Even then, if the pack is drained enough to trigger the low voltage cutoff, it needs to be removed from the car and charged properly.

Also, none of the cheap packs appear to have proper cell balancing circuits. Over time the four cells in series will reach different charge levels and voltages, which means you could end up overcharging one of the cells in series while bringing the string up to voltage. These batteries have a tendency to fail spectacularly (smoke & fire) when that happens. This happened to my neighbor, and that's why he's back to a lead-acid battery.

The LiFePO4 packs are awesome for weight savings, but not so great for longevity or DD use.

Butt Dyno

iTrader: (10)

Yeah I am definitely interested. Thanks for the tip, sounds like a good setup. How loud is it for the daily driving part? When the axleback is removed, do you V-band a turndown in there?

Yeah, looks like the stock bar is 11 lbs and the Tanabe is 7.6
https://www.evolutionm.net/forums/ev...anabe-1-a.html

But I'd be concerned doing that without doing the math of how effectively stiff it is. It's hollow, and the diameter isn't much bigger than the stock piece (25.4 vs 23.8) so hopefully the overall effect is similar. I'm pretty happy with how the car handles now, except at Lincoln ( ) so I don't want to introduce much in the way of change there. The Hotchkis I couldn't find a weight for but I emailed them to see.

For future reference
https://www.evolutionm.net/forums/ev...evo-8-9-a.html
https://www.evolutionm.net/forums/ev...de-evo-ix.html

In my little spreadsheet I have the rear non-ultralite Girodiscs at 11.1 and the Baers at 11.7 - I am not sure I am comparing apples to apples though. That said, if there is a substantial cost difference that's definitely an argument for the Baers.

My car has a relatively easy life and I do have a trickle charger so something more extreme could work. And 75 for 5 lbs of savings is probably a much better ratio than 2 piece rotors

Looks like the 540 cca ones are in the $300 range - does that sound right?

No problem. I don't think I am giving away any real secrets here. The jist of a good STU car is pretty well documented. Hopefully it inspires more people to switch