Z RATED IROC

Just a heads up guys. Do not use any coil over conversion that doesn't come with a mounting plate that mounts underneath the strut tower!!!

The kit I used is one that Profab makes using AFCO springs and hardware. It is a good idea in theory, However it has a Fatal Flaw.
It mounts the upper end of the spring directly on the under side of the Upper strut mounts. (The black adjustable pieces that the strut bolts into)
All of the pressure is on the bottom of that mount. It is trying to pull it off of its perch. It is only held down by 3 small bolts.

With a total of 125 miles on the car the upper strut mounts are bent beyond belief. They are bulging upward and the bolts are barely holding on. If it were to have broken, the spring would have tried to shoot the strut mount through the hood, and the car would have dropped too the ground!!!
I could have been killed if that would have happened at high speed...

Just a FYI. I don't want anyone to have the same problem I did, Or worse yet destroy their entire car.

I ordered Spohns Billet Strut Mounts this morning as well as a 1/4 " plate that Art Morrison makes for their coil over kit. This plate mounts from the under side of the strut tower. With this plate the force is not transfered to the upper strut mount at all. It is directed into the strut tower from underneath. A strut tower brace is Mandatory when using coil overs! I have a 3 point STB.

If I had it to do again I would either use the Art Morrison Coil over kit. (Drag Racing only) OR I would use the AJE kit that has a completely redesigned Spindle , A true Coilover Shock, And bracket that mounts underneath the strut tower.
BTW I talked with Steve Spohn and he is going to design a coil over system for the third gen in the very near future.

BTW Profab did a very good job with the K member and A Arms. I'm very happy with them with regard to those products.

Kandied91z

iTrader: (7)

eh put air on it....




did you find the thread on spacing the strut to solve that problem with your new plates? i forget who was asking but it was discussed recently. basically need to space the shaft out so it isn't having the problem you are now. good luck with it and sorry to hear your luck on the setup, you should get some pictures. by the way does pro-fab know about this?

Z RATED IROC

I talked with Vern at Profab this morning. One thing about him is that he has a "Can Do" attitude. I really appreciate that.
He is very interested in fixing the design.

I told him about the Plate spring mount and he is interested in incorporating it into future design.
One thing he also talked about doing is designing a strut tower brace that not only ties into the normal places but also ties into the frame area at the base of the Tower. This would take the stress off of the tower and keep it from moving.

I will be anxious to see the results of the new designs

I realize that these modifications are adding some of the weight back in, but I for one like trying new things and would like to see this coil over thing work.

Vern also said that if I'm not happy with the results he would trade me for a stock coil spring K member and A Arms.
That is taking care of the customer!

Kandied91z

iTrader: (7)

sounds like he's taking care of you then. in the meantime i would highly recommend trying out art morrisons reverse spring perches. i believe they go for around $35. also might play with the spring choice a bit as well. i went through several lb ratings before i found something that worked.

good luck with it!

Z RATED IROC

What spring rate did you end up with?

I am running a 300# spring right now. 10" long, 2 and 5/8 ID
Is this rate too stiff?
It felt pretty good.
When I would go over any real bumps it would "Bang" like it was hitting the rubber Stops really hard, But it has no Stops on it.

Is this the sound of bottoming out the shock???


Thanks for your help.

Kandied91z

iTrader: (7)

i started with 250 3x10 which was too stiff. put a 150 on and although adjustment was great it was way to soft. settled for 200 but i could have used probably a 180lb setup.

i would say it probably has something to do with the shaft of the strut....i only had that noise happen once and that was when the strut bottomed out.

bjm323

Z, Could you please post a picture of those plates when you get them? Kind of interested on how they look(work).

Z RATED IROC

I will do that.

I got the new Billet units today. They are SWEET!

BTW: The Art Morrison spring mounts apparently are for the 82-86 cars. The bolt holes don't quite line up with the Spohn upper mounts.
The Spohn Upper mounts do look like they line up with the stock ones.

I will have to have the spring mounts manufactured locally.

Kandied91z

iTrader: (7)

really.......hmm no problems with the hunter motorsports piece which is suppose to be what the spohns were coppied off of

Z RATED IROC

Last night I tore things apart to do the inspection and to fix the problem with the new plates I had made up.

First off the Spohn Upper mounts fit perfectly. No problems there.
The art morrison plates were the cause of the bolt alignment issue. Bolt holes were incorrect for the 89 upper mount.

The problem that caused the upper mounts to bend was that the top of the shock body (Outside, Top) was slamming into the upper spring perch when I would hit any significant bump. This is what hammered out the upper shock mount. When I was using a 300# spring.
The spring rate felt good, (It just didn't have enough travel).

When I installed the plates I made it worse. Because I was using a 2 5/8" spring instead of a 3" spring the shock body was now hitting the inside of the spring retainer. (It wasn't a large enough hole for the shock body to pass through when it travels)

I installed a 400 # spring and took out the plates now it doesn't make contact with anything, The spring is just too stiff.

I talked with Vern about this and he was very cool about everything. He said he has never had this problem on any other car, even his big block drag car when it pulls the front tires off the ground.
He wants to examine the entire setup to see why this happened. I will be shipping it all back to him. I told him I'd like to go back to the stock spring locations.
He offered to ship me a new K Member that uses stock spring mounts, No charge. He offered to even pay all of the freight.

Everyone has problems with product from time to time.
It's how they take care of those problems that makes the difference!!!

These guys have excellent customer service!!!


:hail:

twistedwedge

Sounds like you had the same probs I did...you had a 300# spring and i had a 200#, so i guess that answered the question i had about stiffer springs..(dont work). The main prob with the kit vern offers is the travel. The noise you described is exactly what I was having on my car. I measured only about 1.5 inches strut travel when installed at ride height with the kit vern gave me. Little did i know it would cause problems. You got lucky that the strut didnt shove through. On my car it went ahead and "bumped" enough to completely seperate the bearing collar from the mount. I got lucky it was close to the house when it happened. The strut hit the bottom side of my 4"fiberglass hood but didnt push through. I was extremely relieved about that..

I think that vern can come up with a killer design for improvement on this kit..He is excellent at what he does and you are right about the customer svc. part. Every time I have had the silliest question he has always had the patience to answer whatever I needed.

I thought that I would put up the original link to the discussion that some of us had about this same prob. Maybe it would help.
(even though a certain kraut chimed in with some things i didnt waste my time responding to Its a good thread).

https://www.thirdgen.org/techbb2/sho...hreadid=242185

BTW: what strut are you using?

Z RATED IROC

Thanks for the info.
Sorry to hear this happened to you also.
I agree with you that Vern will fix the design. I guess if you only used this kit for drag racing you would never know about this problem.

BTW I am using Koni Yellow shocks & struts.

B4Ctom1

would these help or would we still be faced with the fastener issue?

http://www.hotpart.com/index.php?p=s...f513a7b359d5b7