AST suspension install...with rear subframe bushings

[Justin(OKC)]

Ok, today I had a friend come over to help me (with a few special tools) to do the install of my AST suspension, rear subframe bushings, front and rear swaybars, M3 rear camber links, Mason front strut bar. Yes, you read it correctly.....rear subframe bushings and rear swaybar....in my garage!!!

I got all the parts together (pic below), got the car in the air, and started by disconnecting the brake lines on the drivers side of the back of the car and then we took off the exhaust. After the exhaust was down, we started on the subframe bushings. My friend works at the dealership and had the special tools (I know, kindof cheated). We unbolted the subframe and supported it with a jack, then used the special tools to remove the old bushing and put the new ones in. At the same time we worked on replacing the rear swaybar. After we got the bushings and the swaybars done we replaced the rear camber link, shocks, and springs. We mounted the exhaust back up, I mounted the Nitrogen canisters with some towels to protect them from getting scratched up (until I get some rubber insulator pads tomorrow), and finally bled the brakes.

So, now for the front.....replaced the front swaybar..........

This totally stinks. We thought we would get it done tonight, but somehow the front struts had passenger side camber plates on both of them. I have to send one in to have it fixed. Hopefully we will get it wrapped up soon!!

I had to drive it to test it out. First impression is dang, it's too low. I'll work on that tomorrow. Also, the alignment has so much toe-in that it is very unstable to drive. The back end just wants to dart around all over the place. I'm going to eyeball the toe and camber tomorrow and try to help with that. I will get it aligned after the front is complete.

I cannot believe how good the back of the car seems to ride considering it has close to 800# springs!!! I think I'm going to love the setup and may even want stiffer springs up front.

So, in the end.... I don't think replacing the rear swaybar is as hard as most make it seem. I would do it again in my garage with no problem. The subframe bushings are cake too if you have the special tools to do them. Enjoy....comments welcome!!

Edit: I want to thank my friend, Bryan, for his help in the install of these parts. I could not have done it without him and his expertise!!!!

[Blacky]

Nice

Can I ask what the AST set up cost?

[PrimoM3]

Holy moly that's dumped in the rear... nice setup tho, be curious to hear your review after everything is complete.

[Snertz]

Originally Posted by Blacky

Nice

Can I ask what the AST set up cost?

Buku bucks, almost $5k me thinks : http://www.vorshlag.com/product_info...roducts_id=300

Justin - Very nice setup, AST 5200 series or 5300 series correct?

[vitig]

What parts of m3 do you have in the rear?.

[arrutled]

what are the special tools? screwdriver?

[larryn]

Originally Posted by arrutled

what are the special tools? screwdriver?

My guess is the bushing press extractor. Removing and inserting bushings can be a PITA.

Very nice setup, Justin. Cannot wait to hear your impressions once you get the front squared away, and the alignment done (along with the height corrected).

Any idea what you are planning on for alignment specs? I think you may have the M3 front bits already too... correct?

[Justin(OKC)]

Hey guys, thanks for all the comments. Here are some answers to some questions:

Blacky, the dampers and springs cost me about $4500.

Primo135, it is so dumped it looks stupid. I'm going to try to fix that today but I'm so sore that I have sensation in parts I didn't know were on my body

Snertz, they are AST 5200's.

arrutled, I wish it was a screwdriver. If you look at the pics I posted, there is a shot of the special tool on the passenger rear subframe bushing so that you guys could see it. Without it, I'm not sure how you would get it out (and I have cut bushings out on my E36 M3 before)

vitig, In addition to the swaybar and subframe bushings I've got the rear upper link kit, rear guide rod kit, and the rear lower camber link from the M3. With the rear camber link I have to use M3 shocks

larryn, you got it man. I might have some other pics of the tool if you need some. The hardest part of the install had to do with the front subframe bushings. The M3 bushing install from the top instead of the bottom. What makes it harder is that the subframe is tapered opposite of how the M3 bushings install. To help with the installation we used a hose clamp around the new bushing to compress it and make it easier to go in without stripping/shaving rubber off the bushing. The stock bushing you can twist in your hand, the M3 bushing are solid rubber. HUGE difference. I will definitely post my thoughts when I get it all sorted out. It was too much to do a DIY, but I thought I would post something for those that have some mechanical ability (like yourself). Looking at some of the things you have done and talked about on the forum, larryn, I think you have the ability to do the rear swaybar....no problem. The bushings are cake if you can borrow the tool from someone.

Yes, I do have the front M3 bits as well. I think I have converted almost everything possible on the car. I used a lot of info from orb to help make my decision. Hopefully there will be some sort of toe link available for the rear like orb has on his car. When that occurs, I will buy it. As far as the alignment. I'm trying to get suggestions and ideas. If you have any, please share I'm thinking for the street -1.5 camber front and rear (I may have to do more on the back to fit the forgelines under there....totally different topic that I will go into once I try to test fit them). These are the guidelines that I got from Harold at HP: 1/16" total toe-in for the front with -1 to -1.5 of camber. For the rear, 3/16" total toe-in with -1.5 to -2.0 of camber.

I'll be back under the car a bit today. If anyone has anything they want photographed, just let me know!! Thanks again for all your comments, guys.

Oh, if you were wondering....I think the hardest part of the install was getting the rear muffler hanger (rubber) disconnected to drop the exhaust and getting the rear swaybar bushing mounted up. As I told my friend, Bryan that took the lead on the install.....I've never seen a swaybar bushing that was easy to install.

[arrutled]

Oh i see the tool! nice!

Anyways... questions. 1) It appears you installed the rear guide rod and tension links from the M3 and I want these parts! what kind of difference did you feel from just those? 2) what spring rates did you go for? 450-800?? 3) is this a daily driver? if not, then dont you really want 0 toe if not a little toe out up front. from what I understand when cornering with toe out you have your inside tire making a tighter turn than your outside wheel(which is a good thing). Toe in is good for making your car go straight, because it fights turning.

looks like a great setup! can't wait to see it all done and hear your impressions!!

[Justin(OKC)]

Originally Posted by arrutled

Oh i see the tool! nice!

Anyways... questions. 1) It appears you installed the rear guide rod and tension links from the M3 and I want these parts! what kind of difference did you feel from just those? 2) what spring rates did you go for? 450-800?? 3) is this a daily driver? if not, then dont you really want 0 toe if not a little toe out up front. from what I understand when cornering with toe out you have your inside tire making a tighter turn than your outside wheel(which is a good thing). Toe in is good for making your car go straight, because it fights turning.

looks like a great setup! can't wait to see it all done and hear your impressions!!

In that photo above, we are actually installing the bushing. We didn't have an open end wrench that was the right size so we used a deep socket. We ran out of room so we had to use a bushing as a "spacer" to give us the ability to use the socket. That photo shows the other bushing we were using as a spacer to get the job done. I just realized that without an explanation, that photo looks weird. Springs are as follows:

Swift Springs with Thrust Sheets (392# front/784# rear - 7"/8")
Swift Rear Helper Springs

I totally went off the recommendation of Harold at HPautowerks. After seeing what brracing is doing with their car, I will likely be playing with spring rates. My gut feeling is that I will want a heavier spring up front, but I'm going to try this and see how it goes.

Thanks for the input on the toe. My experience with driving this car out of alignment is that the rear alignment makes a huge difference in how this car drives. It was almost dangerous feeling when I took it around the block last night. Way too much toe-in in the rear. I'll eyeball it today and see if it helps. BTW, raising the back of the car is not as easy as other cars I have had

[larryn]

Justin.. I think Andy is spot on with the alignment specs, for both street and track (on the toe-out)

I'm totally psyched for you to get that.. You have what done what I would call "the divorce kit" in the larryn homestead.

[Justin(OKC)]

Originally Posted by larryn

Justin.. I think Andy is spot on with the alignment specs, for both street and track (on the toe-out)

I'm totally psyched for you to get that.. You have what done what I would call "the divorce kit" in the larryn homestead.

So exactly what would you set the toe for the front and rear?

1/16" toe-out front?
1/16" toe-out rear?

I'm running 0 toe on the front of my M3. The main reason I have done that is that it helps a little with tire wear and a lot of negative camber. It does make the front of the car a little more "darty" but it works fine. Toe-in will make the front more stable as far as in a straight line. I'm not sure I've driven a car with toe-out on the front.

"the divorce kit"....

Again, to everyone posting...I appreciate the input, comments, and advice!!!

[Orb]

Impressive that you got this done with the resource you have. It is a big job and usually takes over 20-30 hours to do a full swap out.

I wouldn’t use all what I have done and expect the same results. There a lot things I did that I never mentioned.

A few notes:

• The springs I am using are 400 lb/in front and 800 lb/in rear with the M3 roll bars but it for 335i and the 1 series needs some so modification to get the same results. This works for me because it is car and setup specific and it not something you can buy right now. I have done a few extra things to increase mechanical grip in the rear and it something I am not sharing at this point. It is possible for 450 lb/in front spring maybe better for higher speed tracks or if you having trouble with mechanical grip in the rear. It is going to be what you like in the end.
• I’m really not sure if there a single person selling suspension components understands how to calculate proper spring lengths for this car. For a 400 lb/in front spring it needs to be 8” long to keep in the linear range. You can get away with a 7” front spring but it the rate will spike as approach 1.5” of shaft compression. The rear spring at 800 lb/in needs to be 8” long which still a bit short but acceptable. Any rate lower than 800 lb/in spring in the rear needs to be 9” long.
• The front struts need to be adjusted for height so that there is very little preload on the spring. It took me two revisions on my camber plated adapters to get this right but it was worth the effort. The front end of my car is considerably more compliant than the KW v3 kit especially on big bumps.
• How much you drop this car is dependant on your spring rate. For the spring rates I need 2.5” on wheel travel front and rear. Dropping the car more than optimal creates a lot of problems. The roll center changes really work against you verses any advantages in CG. It truly a lose situation so if want to drop more then stiffen up the spring but this creates new problems as well. Nothing is easy as you really have to account for all the small details.
• You rear low speed compression is something you want to pay attention to during setting up the dampers.
• The roll bar end links need to be optimized for both front and rear geometry changes. It can make a significant difference.
• I would sugest your rear toe in be set at a minimum of 0.15 to 0.20 degrees. The sub frame still gives a lot even with the M3 bushing upgrade. Anything less and you not going to like late exit rear grip. If you don’t put enough toe in up front your daily drive it will not pleasant….every rut in the road will keep you occupied.

The prototype rear toe links is something I don’t plan to sell or market the links at this time. The next revision of the toe link uses fewer parts and is easier to assemble. I will also increase the stiffness by 20% while retaining the M3 design intent for looks but more importantly function. The testing validation of the links was completed a along time ago and there was significant amount of upfront analysis done before hand. The problem with selling these to the average person is the cost is too high for a small production run. The link is designed to outlast the car under any condition and truly is a no compromise design. If a group of 25 people wanted these then it maybe something I consider and cost could be reasonable. Honestly, it is not on my priority list as I'm working on other things.

Orb

Originally Posted by Justin(OKC)

Hey guys, thanks for all the comments. Here are some answers to some questions:

Blacky, the dampers and springs cost me about $4500.

Primo135, it is so dumped it looks stupid. I'm going to try to fix that today but I'm so sore that I have sensation in parts I didn't know were on my body

Snertz, they are AST 5200's.

arrutled, I wish it was a screwdriver. If you look at the pics I posted, there is a shot of the special tool on the passenger rear subframe bushing so that you guys could see it. Without it, I'm not sure how you would get it out (and I have cut bushings out on my E36 M3 before)

vitig, In addition to the swaybar and subframe bushings I've got the rear upper link kit, rear guide rod kit, and the rear lower camber link from the M3. With the rear camber link I have to use M3 shocks

larryn, you got it man. I might have some other pics of the tool if you need some. The hardest part of the install had to do with the front subframe bushings. The M3 bushing install from the top instead of the bottom. What makes it harder is that the subframe is tapered opposite of how the M3 bushings install. To help with the installation we used a hose clamp around the new bushing to compress it and make it easier to go in without stripping/shaving rubber off the bushing. The stock bushing you can twist in your hand, the M3 bushing are solid rubber. HUGE difference. I will definitely post my thoughts when I get it all sorted out. It was too much to do a DIY, but I thought I would post something for those that have some mechanical ability (like yourself). Looking at some of the things you have done and talked about on the forum, larryn, I think you have the ability to do the rear swaybar....no problem. The bushings are cake if you can borrow the tool from someone.

Yes, I do have the front M3 bits as well. I think I have converted almost everything possible on the car. I used a lot of info from orb to help make my decision. Hopefully there will be some sort of toe link available for the rear like orb has on his car. When that occurs, I will buy it. As far as the alignment. I'm trying to get suggestions and ideas. If you have any, please share I'm thinking for the street -1.5 camber front and rear (I may have to do more on the back to fit the forgelines under there....totally different topic that I will go into once I try to test fit them). These are the guidelines that I got from Harold at HP: 1/16" total toe-in for the front with -1 to -1.5 of camber. For the rear, 3/16" total toe-in with -1.5 to -2.0 of camber.

I'll be back under the car a bit today. If anyone has anything they want photographed, just let me know!! Thanks again for all your comments, guys.

Oh, if you were wondering....I think the hardest part of the install was getting the rear muffler hanger (rubber) disconnected to drop the exhaust and getting the rear swaybar bushing mounted up. As I told my friend, Bryan that took the lead on the install.....I've never seen a swaybar bushing that was easy to install.

[Justin(OKC)]

Orb, thanks for the comments. Admittedly, I don't even come close to having the knowledge you have on this subject. I really tried to use some of the advice I got from you and Harold. I know how you feel about the AST's but I went with them anyway. I knew you had a lot of little "details" that I likely would never be able to accomplish. Information on this stuff and practical experience with it is not that readily available from people here in Oklahoma. I don't get the opportunity to work with someone face to face when it comes to setting it up. As I said, I'm just going to do the best I can and learn as much as I can. I think I got something that I can at least work with and it will allow me to grow and develop my knowledge base when it comes to tuning it.

Harold recommended the spring lengths and rates. I still can't wrap my head around the spring rates, but jumped in on blind faith along with what you did on your car. It is the least amount of spring rate I have ever tried on the front of a car combined with the most amount of spring rate I have ever tried on the rear. I am impessed with how nice the ride seems with just the rear assembled.

BTW, it took two of us about 10 hours to do this in my garage. This included putting the front completely together and then putting the stock stuff back on. It does not include playing with the ride heights and setup. Once everything is on, we will set the height at about 12.5" from the fender lips to the center of the hubs. Then get it aligned so that the 19" tires don't rub. Once we get that sorted, there is a guy in town that I just heard of that will cornerweight the car and finalize the alignment settings. Orb, if you have any suggestions at all please PM me!! Although I don't always understand all of what you suggest, it does help!!

[vitig]

According to you, what order should we do?. I would like to get your configuration. But I have no money for everything, to begin shortly.

Thank you for your wisdom

[Justin(OKC)]

Originally Posted by vitig

According to you, what order should we do?. I would like to get your configuration. But I have no money for everything, to begin shortly.

Thank you for your wisdom

I am no expert, but I would do:

M3 front swaybar
M3 Front Lower Wishbone Kit
M3 Front Tension Rod Kit
M3 Rear Upper Link Kit
M3 Rear Guide Rod Kit

Personally, I think this is where to start and is the best bang for the buck. I think this will cost about $1500 or so...maybe less (can't remember). If it is the look you are going for....I'm not quite sure what to recommend.

[brracing]

Justin,
We have really enjoyed working with you and with our latest information from the BBK addition I think we are going to be playing with spring rates again as right now we feel as though we are too soft.
With that said if anyone else is in need of help please let us know as that is what we are here for.
Congrats on the upgrades Justin and we look forward to your project and what you are doing.



Robb

[vitig]

[QUOTE=Justin(OKC);6214238]I am no expert, but I would do:

M3 front swaybar
M3 Front Lower Wishbone Kit
M3 Front Tension Rod Kit
M3 Rear Upper Link Kit
M3 Rear Guide Rod Kit

I agree whit you ,i have maked the first, m3 front swaybar.

I think in next about front lower and front tension or the rear swaybar.What what would you do?.

[Justin(OKC)]

[QUOTE=vitig;6215361]

Originally Posted by Justin(OKC)

I am no expert, but I would do:

M3 front swaybar
M3 Front Lower Wishbone Kit
M3 Front Tension Rod Kit
M3 Rear Upper Link Kit
M3 Rear Guide Rod Kit

I agree whit you ,i have maked the first, m3 front swaybar.

I think in next about front lower and front tension or the rear swaybar.What what would you do?.

Personally, I wasn't going to do the rear swaybar without doing the subframe bushings. I still hold true to that decision.

[vitig]

´Thanks.

[Justin(OKC)]

I just wanted to shout out a big thank you to Terry Fair for answering the phone Saturday night, Harold at HPautowerks for helping with the follow-up, Brian at AST-USA for getting my PM in Holland and forwarding it back to his office, and then finally to Stuart at AST-USA for working out the details of getting things fixed up. I shipped the strut last night and I'll have it back tomorrow!! I'm stoked Thanks guys!!!!

[arrutled]

What was wrong?