Rear Shock Opinion
 

I need your opinions on my rear shocks. There are not many guys around that have built one of these B&B cars. It takes some detailed explanation so please bare with me.

I am trying to determine if I have the right rear shocks or were the mounting brackets made wrong. For a few years I have seen other guys B&B builds with the rear shock snap ring in the upper groove. Mine just didn't seem to work that way. With a 10" spring it would make the car set way to high, so I put mine in the lower groove. I have a fender lip to ground height of 28", which looks about right to me. The coil over picture was taken at ride height, on the ground. That 10" spring barely fits at the end of adjustment.

In this process I also realized that my shock is way to close to the end of it's compressed travel. So, do I have the wrong shock or were the mounting points built wrong. Right now the shock ride height is 12.75" eye to eye, but I am not sure which shock I have. The number on the shock is 806990023711 which may be the new QA-1 number 7564; not sure, they are closed until Tuesday. The 7564 shock lengths are 11.43”-17.53”. The center would be about 14.48”, way off from the 12.75” distance I have at ride height. I will take the shocks apart and measure them when I get some time.

I am thinking the upper tab mount looks to low and could be cut off and shorted maybe 3/4", changing my shock ride length to 13.5 at right height. The axle mounting points may be off, who knows. I have about 1" or so between the bump stop and the axle. Another option is to change shocks and go with the 5774 shock which has 10.3"-15.27" measurements, but cost more money. My intention is to go with heavier springs but I wanted to avoid buying new shocks to. . It would be nice to determine why the shocks I got with the kit don’t seem right.

If you have a B&B and know the part number of your QA-1 shocks or can shed some light on this subject it would be helpful.

Thanks.
http://www.clubcobra.com/photopost/d...gs_Medium_.jpg
http://www.clubcobra.com/photopost/d...16_Medium_.jpg

looks like you need a shorter spring at the least, and from your measurements you have only 1" of bump before the shock bottoms.

That's right. I'm thinking of going with a 9" 250 lb. spring. I need to determine this shock issue first. Either fix the mounting points or go with a shorter shock. With the shorter shock I could cut the bump stop 1/2", put in the stiffer spring and have more travel. It would be nice to learn why I have to do this. Wrong mounts or wrong shocks?

I installed a 2 1/2" x 10" 275 lbs spring on a QA1 shock for Mike's B&B last summer. Shock, QA1 part # 7564. but I don't remember the lenght.
Fender height was 27 1/4 or 27 3/4".
this was the same set up that has been on this car for nine years, I just replaced the shocks and kept the old springs.
Dwight
picture is with the rear end hanging


http://www.clubcobra.com/photopost/d...19_resized.jpg

Good to hear from you Dwight. It's hard to tell but that shock looks shorter than mine. Maybe I have the wrong shock. I can't tell about the upper mount.

I skimmed your post so I haven't worked your numbers. But, a couple rule of thumbs.
- The shock should have 60% of travel available at ride height. 60/40 compression/droop
- Run the longest spring possible to reduce coil bind.

This is what I am running.
Rear Coil over hardware CK1951 COIL-OVER KIT - 75 & 79 SERIES, 2 1/2" I.D. SPRING, W/O JAM NUT BB (QA1)
Rear shock 7563 BB (QA1)
Rear Springs 10CS185 Coil-Over Spring, 185 lbs./in. Rate, 10 in. Length, 2.5 in. Diameter, Chrome BB (QA1)

Thanks for the information Larry. I just have to determine what shock I have. If this 806990023711 crosses over to 7563 or 7564 shocks. It looks like the one I have may be to long.
Larry what is your fender lip to ground height and what do you think about the 185 lb. springs.

Added:
One other thing. Does your upper mounts hang down as far as mine?

I'm going to the shop today and I still have the old shock. I'll measure it and take pictures.

I'll post tonight

Dwight

Thanks Dwight. You're the man!!

Wayne maybe this photo will help. This is on jack stands with the rear at ride height. When the car is on the ground it will compress about another half inch. Carrera Hypershock I hope I attached the photo the right way. I'm an amateur at this.
Lou

Wayne I can see the problem. My lower eye is attached below the lower trailing arm bolt. Your attachment is above it. Quite a difference!!
Lou

Lou, so it looks like your shock is running about 14 1/4" or so at ride height compared to my 12 3/4" with a 1 1/2" difference. Yours would be close to center for that 7563/7564 shocks. Even if I cut off the upper tabs and reweld some higher it's still not going to be enough.

You know I called B&B and told them this just didn't look right with the shock in the higher clip notch. They said it would settle down when the weight gets on it. I guess I will see what they have to say tomorrow.

Thanks a lot Lou.

old shock is marked 3364 and it's 11" closed and 17" extended

Dwight

Thanks Dwight. I have that number in my notes but don't know where I got it. That must have been replaced by the 7564 shock. The lengths are similar.

We will see what B&B has to say tomorrow. Does anyone know if they are still in business?

I may be doing a how to fix a defective B&B rear shock mount thread. :LOL:

Thanks all your guys on this.

Just to tie up some lose ends, I called QA-1 and the 806****** long number I had was the UPC code and I do have the standard 7564 shock that comes on B&Bs. The 3363 that Dwight gave is the older version of new 7563. The last number is the valving. So a 3 is softer than the 4. So Larry's shock 7563 has softer valving than my 7564.

At this point my options are, redo the shock mounts, or buy shorter shocks. I was considering buying stiffer springs anyway.

I called B&B and left a message for Bryan Anderson to call me after explaining the situation.

SUMMARY
I want to summarize the situation so those that may have the same situation understand. I bought my kit the end of may 2009. It is not on the road yet, but close. My vin ends with 411. The 7553/7554 rear shock that comes on these cars has a travel of 11.43 to 17.53, with about a 6" total travel. The mid-travel point for this shock is 14.48". My shock ride height now is 12.75". My distance between my bump stop and axle is just about 1.25" with a ride height of 28" fender lip to ground. If I hit a hard pump more than 1.32", which it will, the shock will bottom out and will most likely break. It only has to compress the bump stop .07" to bottom out.

My fender lip to ground is 27.5" an as far as the 185 lbs springs, I'm not sure my wife would rided with me if they were any stiffer! I have bottomed out on sevier bumps but very very rarely. I am 6,2 240 so I do put some weight into it!
My mounts were bolt on the top, not welded so they are a little different. Mine had a U shaped piece that had a bolt the went through the upper frame with a nut on the other end. But it looks very similar.

SOLUTION UPDATE

B&B did call back and we discussed the situation. There was a short period of time that B&B contracted out their metal fabrication. It turns out that mine was one of a few cars that the lower shock mount on the axle was made to high. The solution is to weld a new tube on the bottom of the bracket where it narrows and that will put the shock at the proper ride height.
B&B will send me the metal tubes and I will weld them in.

I think this is the most reasonable solution.

Thanks Larry, that is helpful. The wife is very important if we want support for building impractical cars.

I have the same top mount as Larry. Last numbers on the vin are 209. I believe it was late 2002 build. I went from 185 to 225 and found it to be better. I ended up with 300s. Wife said, "little stiff" I just laughed , wait until she feels the solid engine mounts this spring. Yea, - MY HOTROD :D