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: 51/49 weight balance achieved on Subaru STI


Miche@BJAutohaus
06-08-2010, 08:36 PM
Ever since we announced our corner balancing service, we have a number of customers coming in particularly to get their cars balanced and ready for the track. Here are just some of them.

http://photos-h.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404498403521_510758521_4216791_5937748_s.jpg (http://sphotos.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404498403521_510758521_4216791_5937748_n.jpg ) http://photos-d.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404498418521_510758521_4216793_7185628_s.jpg (http://sphotos.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404498418521_510758521_4216793_7185628_n.jpg ) http://photos-a.ak.fbcdn.net/hphotos-ak-snc3/hs354.snc3/29308_404498428521_510758521_4216794_5363770_s.jpg (http://sphotos.ak.fbcdn.net/hphotos-ak-snc3/hs354.snc3/29308_404498428521_510758521_4216794_5363770_n.jpg ) http://photos-c.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404498168521_510758521_4216788_6032736_s.jpg (http://sphotos.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404498168521_510758521_4216788_6032736_n.jpg ) http://photos-b.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404497833521_510758521_4216771_5395052_s.jpg (http://sphotos.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404497833521_510758521_4216771_5395052_n.jpg )
Do you like AST (Advanced Suspension Technology) products? We love them! This E36 M3 is now rocking AST's sportline mono-tube high pressure, coilover shock absorbers!

http://photos-a.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404497923521_510758521_4216780_4053439_s.jpg (http://sphotos.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404497923521_510758521_4216780_4053439_n.jpg ) http://photos-d.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404497838521_510758521_4216772_3001447_s.jpg (http://sphotos.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404497838521_510758521_4216772_3001447_n.jpg )
For this Blue WRX STI, we installed KW V3 custom valved coilovers and we were able to achieve a 51:49 weight distribution through corner balancing. I believe the stock suspension yields a 58:42 weight distribution.

http://photos-h.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404497828521_510758521_4216770_3635779_s.jpg (http://sphotos.ak.fbcdn.net/hphotos-ak-snc3/hs334.snc3/29308_404497828521_510758521_4216770_3635779_n.jpg ) http://photos-c.ak.fbcdn.net/hphotos-ak-ash1/hs343.ash1/29308_404497803521_510758521_4216769_7403249_s.jpg (http://sphotos.ak.fbcdn.net/hphotos-ak-ash1/hs343.ash1/29308_404497803521_510758521_4216769_7403249_n.jpg )
Here is another Impreza that came in for suspension work and corner balance.

Bath Tussue
06-09-2010, 08:58 PM
"we were able to achieve a 51:49 weight distribution through corner balancing"

may I ask how?
I did not know weight distribution can be adjusted by corner balancing.

Lomac
06-09-2010, 09:15 PM
It's done by transferring the load from one set of diagonals to another (FR to RL, FL to RR). At least, that's how I understand it. The car still technically has the same static weight distribution.

dink
06-09-2010, 09:16 PM
Tightening the spring will increase the weight exerted on the scale.

So for example: if you lower one corner, you are taking weight away from that corner and its diagonal opposite. The other two corners will increase in weight. Similarly, if you raise one corner, you are adding weight to that corner and its diagonal opposite. The other two corners will decrease in weight.

Does that make sense?

!Aznboi128
06-09-2010, 09:29 PM
^ yup, basically

high = heavy

Rich@BJAutohaus
06-09-2010, 09:53 PM
it's kind of like leaning back.
if you're standing on a flat surface and lean back, you're putting more weight
on your heels.

so if you look at that blue STI after the corner balancing, the front does look
slightly higher than the rear to achieve a more even balance to a factory
front heavy subaru.
that balance of course takes into account the weight of the owner of that car and
an even balance has been achieved on front left and front right tire as well.

KiDEclipse
06-09-2010, 10:28 PM
http://www.youtube.com/watch?v=_YdtqHxbC8Y&feature=related

ericthehalfbee
06-09-2010, 10:30 PM
It's a confusing term.

Let's say you had a 3,000lb car with a 60:40 weight distribution. You'd have 1,800lbs on the front wheels and 1,200lbs on the rear wheels. No matter what you do to change the ride height or spring rates, you're not going to change that 60:40 weight distribution (at least not by much).

However, if you look at all 4 wheels you might have something that looks like this:

LF 950lbs RF 850lbs for a total of 1,800 lbs
LR 570lbs RR 630lbs for a total of 1,200 lbs

We still have the same 1,800lbs on the front and 1,200lbs on the rear.

If you add up the opposing corners you get:

LF + RR = 1,580lbs or 53%
RF + LR = 1,420lbs or 47%

This gives us a ratio of 53:47, even though the front/rear is still sitting at 60:40.

If we add up the left & right sides we get:

LF + LR = 1,520lbs or 50.6%
RF + RR = 1,480lbs or 49.3%

This gives us an almost perfect 50:50 side-to-side.

So you can see that with a single vehicle you can have several different "ratios" depending on what you're actually measuring. :)

J____
06-09-2010, 10:53 PM
so it'll drive like a boat now?

Rich@BJAutohaus
06-09-2010, 11:14 PM
i'm talking front to rear 51/49
i'll try and find the actual corner weight specs tomorrow

It's a confusing term.

Let's say you had a 3,000lb car with a 60:40 weight distribution. You'd have 1,800lbs on the front wheels and 1,200lbs on the rear wheels. No matter what you do to change the ride height or spring rates, you're not going to change that 60:40 weight distribution (at least not by much).

However, if you look at all 4 wheels you might have something that looks like this:

LF 950lbs RF 850lbs for a total of 1,800 lbs
LR 570lbs RR 630lbs for a total of 1,200 lbs

We still have the same 1,800lbs on the front and 1,200lbs on the rear.

If you add up the opposing corners you get:

LF + RR = 1,580lbs or 53%
RF + LR = 1,420lbs or 47%

This gives us a ratio of 53:47, even though the front/rear is still sitting at 60:40.

If we add up the left & right sides we get:

LF + LR = 1,520lbs or 50.6%
RF + RR = 1,480lbs or 49.3%

This gives us an almost perfect 50:50 side-to-side.

So you can see that with a single vehicle you can have several different "ratios" depending on what you're actually measuring. :)

Rich@BJAutohaus
06-09-2010, 11:15 PM
quite the contrary,

it handles a lot better now,


so it'll drive like a boat now?

G-spec
06-09-2010, 11:24 PM
good job! and hell yes for AST!
StanceWorks just recently teamed up with AST to create a brand new setup called ZeroClearance, made specifically for slammed 350z's and G35 coupes...

I'm on the list to receive one of their first batches soon as they're released.... and now I know who to go too for corner balancing and suspension tuning, wicked!



http://i441.photobucket.com/albums/qq139/Royal_T_album/AST1.jpg?t=1269781980

http://i441.photobucket.com/albums/qq139/Royal_T_album/AST2.jpg?t=1269782051

Rich@BJAutohaus
06-09-2010, 11:40 PM
:thumbsup:
now here's a man who knows a little something about suspension.

AST's are king!

i believe that S54 engined E36 has that AST/Stanceworks coilover setup too

good job! and hell yes for AST!
StanceWorks just recently teamed up with AST to create a brand new setup called ZeroClearance, made specifically for slammed 350z's and G35 coupes...

I'm on the list to receive one of their first batches soon as they're released.... and now I know who to go too for corner balancing and suspension tuning, wicked!



http://i441.photobucket.com/albums/qq139/Royal_T_album/AST1.jpg?t=1269781980

http://i441.photobucket.com/albums/qq139/Royal_T_album/AST2.jpg?t=1269782051

Levitron
06-10-2010, 12:16 AM
Is that Art's blue STi?

Oversteer
06-10-2010, 12:33 AM
yup, that's my car,

The KW's are Racecomp Engineering Tarmac 2 coilovers. Through thorough testing, they have spec'd the valving and worked jointly with KW to produced a custom valved suspension system with matching springrate for imprezas. The camber plates are made by Vorslag, same company that made the plate you see on the AST shocks. They have huge bearings to withstand load.

I'm definitely happy with the setup, the shocks provide better-than-stock comfort, but crazy performance when pushed. I also have a set of RCE sway bars that was put in by Jason at Autohaus.

Thanks Rich and Jason and the rest of the ppl at Autohaus. I'd recommend them.

Artz

!e.lo_
06-10-2010, 12:35 AM
ddaaamn.
I'll be doing a whole lot to my suspension this summer.
Do you guys offer a corner balance + alignment package?

Oversteer
06-10-2010, 12:37 AM
ddaaamn.
I'll be doing a whole lot to my suspension this summer.
Do you guys offer a corner balance + alignment package?

Mine was cornerbalanced AND aligned :)

dink
06-10-2010, 08:13 AM
Jason's been asking me to do a corner balance on my ITR. But I haven't had the time! Maybe this Saturday? *hint hint*

shenmecar
06-10-2010, 08:54 AM
im confused to how this works..
Posted via RS Mobile (http://www.revscene.net/forums/announcement.php?a=228)

ericthehalfbee
06-10-2010, 09:13 AM
^ Lots of info online.

http://grassrootsmotorsports.com/articles/understanding-corner-weights/

TOPEC
06-10-2010, 10:15 AM
im confused to how this works..
Posted via RS Mobile (http://www.revscene.net/forums/announcement.php?a=228)

it's not hard, basically u adjust all 4 coilover's ride height so that all four corners have similar weight readings.

SumAznGuy
06-10-2010, 11:29 AM
it's not hard, basically u adjust all 4 coilover's ride height so that all four corners have similar weight readings.

So I can go to any other shop with scales and get them to corner balance my car, right?

N.gen
06-10-2010, 12:03 PM
:thumbsup:
now here's a man who knows a little something about suspension.

AST's are king!


i've never seen this car at Mission or PR? Do you track it by any chance or strictly street driven car with higher-end coilover shocks;AST?

G-spec
06-10-2010, 12:04 PM
damn, as soon as my wheels and AST coils arrive I'm getting this done asap!!

My car is a cow, it weighs 3770lbs with a full tank and me inside it. Hey BJ AutoHaus guys, can you guys corner balance with me in the car ?? I weigh 200lbs so it's quite a bit of weight. Or just put 200lbs of weights on my drivers side whatever is safer.

thanks let me know

ronald55555
06-10-2010, 02:33 PM
I agree with eric the half bee. Corner balancing can only adjust your cross weight balance, ie wedge.

Just by a rough calculation/estimation, using numbers given by Rich:
Stock Front:Rear = 58:42
New Front:Rear = 51:49
Assumptions:
weight = 3000lb
cog = 25" (over estimate)
stock chassis rake is 0 degrees

With those numbers, in order to acheive a front:rear balance of 51:49, the chassis would need to be raked by 13.5 degrees, and that is using a calculation that gives a low estimate. This also means the front end needs to be raised by 23.3".

Not trying to be a smart ass here, but just saying going to 51:49 from 58:42 is not going to happen. Could very well be Rich has just mistaken on the 58:42 number, I wouldn't doubt the 51:49.

RRxtar
06-10-2010, 02:50 PM
did you achieve this weight distribution improvement by adding a sub box with two 12"s in the trunk?

Rich@BJAutohaus
06-10-2010, 03:16 PM
lol my mistake guys,

it is infact the cross weight balance,
i misunderstood the technician when he told me,

again, my apologies.

for the record though, the car does handle incredibly

Rich@BJAutohaus
06-10-2010, 03:20 PM
i've never seen this car at Mission or PR? Do you track it by any chance or strictly street driven car with higher-end coilover shocks;AST?

i've only auto crossed it so far, and was not happy with the previous
suspension setup,
i definitely plan to take it to the track now that these coilovers are on.

how did you know it was my car by the way?

Rich@BJAutohaus
06-10-2010, 03:21 PM
damn, as soon as my wheels and AST coils arrive I'm getting this done asap!!

My car is a cow, it weighs 3770lbs with a full tank and me inside it. Hey BJ AutoHaus guys, can you guys corner balance with me in the car ?? I weigh 200lbs so it's quite a bit of weight. Or just put 200lbs of weights on my drivers side whatever is safer.

thanks let me know

definitely!
we had someone with similar weight(to the owner) sit in the car when we did the blue STI

N.gen
06-10-2010, 03:22 PM
i've only auto crossed it so far, and was not happy with the previous
suspension setup,
i definitely plan to take it to the track now that these coilovers are on.

how did you know it was my car by the way?

just a guess.

What suspension did you previously have that wasnt handling so well?

Are those the AST 5100s or 4100s?

Rich@BJAutohaus
06-10-2010, 03:23 PM
yup, that's my car,

The KW's are Racecomp Engineering Tarmac 2 coilovers. Through thorough testing, they have spec'd the valving and worked jointly with KW to produced a custom valved suspension system with matching springrate for imprezas. The camber plates are made by Vorslag, same company that made the plate you see on the AST shocks. They have huge bearings to withstand load.

I'm definitely happy with the setup, the shocks provide better-than-stock comfort, but crazy performance when pushed. I also have a set of RCE sway bars that was put in by Jason at Autohaus.

Thanks Rich and Jason and the rest of the ppl at Autohaus. I'd recommend them.

Artz

thanks for your kind words Art,:)
i'm glad you're happy with the set up. :thumbsup:

Rich@BJAutohaus
06-10-2010, 03:24 PM
just a guess.

What suspension did you previously have that wasnt handling so well?

Are those the AST 5100s or 4100s?

they're the 4100's

i previously had the H&R springs/ Koni adjustables set up,
they don't even compare to the ASTs performance wise

N.gen
06-10-2010, 03:29 PM
just curious what spring rates are you running for the 4100s?

you also got the AST reinforced shock mounts?

those are the new revised version of the Vorshlag camber plates with the red anodizing correct? looks a lot better than the ones I have without the anodizing...

Rich@BJAutohaus
06-10-2010, 03:40 PM
i'm running 550 in the front, 650 in the rear,
and i'm running E46 M3 RSMs

and yes! those are the latest version

what do you drive?

just curious what spring rates are you running for the 4100s?

you also got the AST reinforced shock mounts?

those are the new revised version of the Vorshlag camber plates with the red anodizing correct? looks a lot better than the ones I have without the anodizing...

Oversteer
06-10-2010, 03:48 PM
I will post some numbers for the weight distribution soon

AWDTurboLuvr
06-10-2010, 03:56 PM
i've only auto crossed it so far, and was not happy with the previous
suspension setup,
i definitely plan to take it to the track now that these coilovers are on.

how did you know it was my car by the way?

Did you come out to any UBC events this year? I've seen a similar M3 with that motor before and I'm wondering if it's the same car.

Rich@BJAutohaus
06-10-2010, 05:00 PM
Did you come out to any UBC events this year? I've seen a similar M3 with that motor before and I'm wondering if it's the same car.

i don't think i've gone to any this year,
i've gone to a few last year though

Oversteer
06-10-2010, 05:32 PM
The 50.9% left cross (driver sitting on left in america)

FL - 1015
FR - 996
RL - 768
RR - 688
Total weight with full fuel and filled IC spray tank = 3467lbs
http://robrobinette.com/corner_weight_calc.htm

here's a good calculator to tell you how it's calculated and optimal settings for the car