GB: DRM Coilovers

[HAWAIIZR-1]

Originally Posted by mgg

Well, Merry Christmas!! Bob and I worked on the rear today hoping to finish it up but we didn't quite get there. Holes drilled per Carters bracket, trailing arm bolts reversed, bushing cut and shocks/coils assembled. Trying to mount the shock/coilover we cannot seem to get the carter plate to line up with the holes. It is about a 1/4" short of lining up to the hole towards the front of the car. I drilled out the area revealed when I bolted up the carter bracket but we cannot seem to get it forward enough with the assembled shock, bushing, carter bracket etc. It is as if the bushing will not allow us to get unit moved toward the front of the car so that the bolt holes will line up. Is the area revealed by carters bracket the ONLY metal that needs to be removed. The frame that was visible through the hole in carters bracket is removed. Again, any help would be appreciated. It is puzzling. Best wishes for a Merry Christmas to all.

Thanks for keeping us posted on the trials and tribulations on this intall and making it easier for all those that follow you. Great that you have Bob's help and I'll be doing this solo when I get back to Hawaii; I don't think I want to tackle this here in Japan and have my car stranded in case I have to ship it on short notice. I'm curious to know the findings about the brackets. Please post photos if you can. Happy Holidays!!!

Craig

[mgg]

Craig, I would agree that I would wait to do the install until you get back. It can prove to be a bit frustrating at times. After thinking about the problem I am having, I am fairly confident that the frame that was exposed by Caters bracket , then removed is not large enough to allow the top bushing to slide forward towards the front of the car. I blieve the top bushing is hitting the frame and this is what is preventing the plate to line up with the holes in the frame. It is about 1/4" shy of lining up. I am goint to get out in the garage today and see if I can measure it with some calipers. I do feel that if I open up the width of the area that was cut out using Carters bracket that this will allow the plate to move enough to line up. I made the assumption that just removing the area exposed in the hole of Carters bracket would give me the clearence needed. I do not think that was a good assumption. The only difference between bolting up the bracket by itself or with the shock installed through it is the bushing. I hope if I enlarge the opening this will allow the bushing to forward enough to make this all line up. ( I knew there was a reason I kept putting off buying coilovers) it is a pain in the ***, and I have not even got to the front yet. It will be worth it in the long run I hope. It is snowing I wouldn't be driving the car anyway. Bob has been good friend coming over and working on the car. It is much more fun with two rather than being by yourself. It is easier to laugh off problems! I will keep you posted.

[Aurora40]

There are a few things that we did/need to do that I thought I'd clarify.

One is, Pantera, we did not follow your suggestion for cutting the bushing. Cutting the bottom one seemed like a bad idea, as it is not that thick to begin with, and cutting 1/2 of it off would have left almost nothing. I do appreciate the help though.

The bottom bushing is taking all the force of the car slamming into bumps, while the top bushing would only take the unsprung weight, and only ever 1g worth of acceleration on it. So cutting the top bushing seemed more prudent. We also only cut about 1/4 off of it, not in half. This was enough to assemble the shock around Carter's plate. And we did not reuse the black flat washer, just the gold top one.

Additionally, Mike was of the impression that you only have to cut the frame where you can see through Carter's plate. I don't know if that was in a write-up or Carter said that, or where it came from. But it is not true.

If you look at the crude drawing I posted, bolting the plate in place and cutting the overlap will only make a hole big enough for the center section of the bushing assembly. The top is quite a bit wider than that, though. So that will not be enough material removal to insert the shock into the frame, and slide it forward to bolt it in place. It will not be able to slide forward because the bushing will not fit in the notched out area.

Mike has been grinding this out a bit more, but it seems that the plate doesn't address the concern of "how close to the bolt hole can you grind the opening before the remaining material isn't strong enough?" You still have to guess, test-fit, and hope you don't make a mistake.

I do wonder if the stock rubber bushing would let you trim less, as it is much more rounded in shape, and may slide over some small amount of the frame when pushed forwards. I don't know why a poly bushing is included with the stock kit, if this is "needed" to address some engineering/stress concern, or if it's just assumed most people think poly is better, so they toss it in as a nice gesture (or to offset the lack of any instructions)?

[carter200]

Here is the link to the proper install: http://www.zr1.net/forum/showthread....install&page=9

I have sold over 30 of these kits with NO issues. Make sure you are using the right on the right and left on the left and follow the instructions or ask the many who have installed their kits how they did it with NO issues.....

[mgg]

Carter, this post is NOT to criticize the brackets, it is just trying to find out if additional frame other than the material exposed by your bracket needs to be removed. I was thrilled when I bolted up your bracket and was able to use the bi metal hole saw that fit perfectly in the hole in your bracket for the shock. It provided the perfect guide to cut out the frame area exposed in the hole. I assumed after doing that , the schock would then just mount up when assembled with the bushings etc. Unfortunatley it appears about a 1/4 " of additional frame area towards the front hole has to be removed in order for the schock and bushing to move forward so that your bracket holes and the frame holes line up. This is due to the width of the bushing hitting the frame and preventing it from moving forward. Your brackets are fine and well made and need to be made the way they are for this to work. I guess I assumed that when the exposed frame in the hole of your bracket was removed the schock would just bolt up like it was when I drilled out the frame. No where in the installation does it say anything about removing additional frame material which I find a bit odd. Do not interpret this as criticism, just wanting to know if anyone else had this issue . I have followed the instructions on the forum reversing the control arm bolts, shaving the bushing etc. I even compared it to my race car that I installed these same coilovers on without your bracket just to compare. Hopefully I will get this figured out but if you know anyone who has done this and did not have to cut out additional frame material I would like to hear from them. Again, NO PROBLEMS WITH YOUR BRACKETS. They match up with the holes in the frame, they will help strengthen the area, they allow the use of the hole saw to cut out the frame area exposed in the hole. One the schock is installed in the bracket I cannot get the hole in the bracket to line up with the frame holes. This has to be caused by the bushing and I will need to remove more frame material. Approx 1/4". That should do it.

[carter200]

I was just trying to get others that have installed the kits to chime in and give you more choices in feedback as it seemed like it was going no where for you. I did NOT feel threatened so do not worry about that. Just trying to get more info for you.......

[Aurora40]

Originally Posted by carter200

Here is the link to the proper install: http://www.zr1.net/forum/showthread....install&page=9

I have sold over 30 of these kits with NO issues. Make sure you are using the right on the right and left on the left and follow the instructions or ask the many who have installed their kits how they did it with NO issues.....

Hey Carter, if you look at that posting, the part that is missing is how much to cut the rear frame.

The link at the beginning of that thread, back to CF, has a picture of the frame cut. But then the author states: "Here, I have done some cutting but in actuality, I did remove some more."

So it's not clear how much more has to be removed in order for the shock to bolt up. You have to guess at it, which of course opens the possibility for guessing wrong.

[HAWAIIZR-1]

Originally Posted by mgg

Craig, I would agree that I would wait to do the install until you get back. It can prove to be a bit frustrating at times. After thinking about the problem I am having, I am fairly confident that the frame that was exposed by Caters bracket , then removed is not large enough to allow the top bushing to slide forward towards the front of the car. I blieve the top bushing is hitting the frame and this is what is preventing the plate to line up with the holes in the frame. It is about 1/4" shy of lining up. I am goint to get out in the garage today and see if I can measure it with some calipers. I do feel that if I open up the width of the area that was cut out using Carters bracket that this will allow the plate to move enough to line up. I made the assumption that just removing the area exposed in the hole of Carters bracket would give me the clearence needed. I do not think that was a good assumption. The only difference between bolting up the bracket by itself or with the shock installed through it is the bushing. I hope if I enlarge the opening this will allow the bushing to forward enough to make this all line up. ( I knew there was a reason I kept putting off buying coilovers) it is a pain in the ***, and I have not even got to the front yet. It will be worth it in the long run I hope. It is snowing I wouldn't be driving the car anyway. Bob has been good friend coming over and working on the car. It is much more fun with two rather than being by yourself. It is easier to laugh off problems! I will keep you posted.

Thanks for sharing your thoughts and I hope it all works out. Yes, I will definitely wait until I have the right location and resources before I tackle this project. It is great that you have all the help from here and at your location as I can't imagine facing this alone. Sounds like a good winter project and it will be worthwhile in the end and trying to figure it all out. Best wishes.

[mgg]

OK guys, for those of you who are interested I have been grinding away on the frame this morning for about 3 hours. I now am able to mount the shock the mounting plate bushings etc. into the stock bolt locations. To make this so that others do not have the same questions and issues I have had, I am going to take some pictures of what the hole looks like after cutting out the area exposed by Carters plate and what the finished hole needs to look like to be able to mount the plate with the schock/coil/bushings. It is a BIG difference. To my knowledge this has not been documented as part of the installation procedure as it is the biggest pain in the butt to do. I went through a brand new hardened rotary file bit and a brand new grinding stone bit on one side only. I used a pneumatic grinder capable of 20,000 rpm. WEAR GOGGLES! I am pleased that the right side is done and now to begin the left. The pictures will clearly demonstrate what needs to be done to mount the coilovers. I will try to have Bob post the pictures as he is MUCH better at that than me.

[Aurora40]

Here's Mike's pictures.

Hole saw through the Carter bracket:



And expanding that hole until the shock actually fits: