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Trying to get my head wrapped around cutting front bump stops by NetCam
Started on: 10-31-2013 10:06 PM
Replies: 5 (596 views)
Last post by: Khw on 11-01-2013 08:44 AM
NetCam
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Report this Post10-31-2013 10:06 PM Click Here to See the Profile for NetCamClick Here to visit NetCam's HomePageSend a Private Message to NetCamEdit/Delete MessageReply w/QuoteDirect Link to This Post
I'm about to lower my front end with Eibach springs, which say they will drop the car about .8". I've read in quite a few posts that I will need to shorten my front bump stops or my suspension will be sitting on them, leading to a very bumpy ride. I looked at the diagrams on WCF, and although I understand the concept, when I play it through my head, I don't see how it's going to work. If you cut something that is on an angle, then take a piece out of it, then the size of the openings on the resulting two pieces will no longer match up. Pardon the crude one dimensional drawing, but this was the easiest way I could try to visually portray where my head is at. Anybody out there can help me with this?

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Blacktree
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Report this Post10-31-2013 11:14 PM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageClick Here to Email BlacktreeSend a Private Message to BlacktreeEdit/Delete MessageReply w/QuoteDirect Link to This Post
I also have Eibach springs in front, but never cut the bumpstops... for the same reason you just mentioned. And speed bumps are the bane of my existence.

I can tell you from personal experience that bottoming out the front suspension is NOT fun. The suspension doesn't ride on the bumpstops, but comes close. There's maybe an inch of space, at the most. It isn't enough.
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Patrick
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Report this Post11-01-2013 12:28 AM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post

The taper of the cone(s) isn't very much, so when you cut out a 3/4" band, there is not a huge difference in the relative diameter of the two pieces that are to be welded together. As long as the two halves touch in at least three places, you're golden. (Hint - you can ding the edges so that the pieces are no longer perfectly round where they meet.)

 
quote
Originally posted by Patrick:

I cut off two complete coils from both the front and back springs of my '84. The back was fine, but the front was definitely sitting on the bump stops. Made for a rough ride! I got some assistance from Fiero club friends of mine (with welding equipment) to cut and weld the metal cones. I had read that removing 3/4" was ideal, as removing more could possibly lead to the shocks bottoming out. Not a good thing!

Pictured below is a cone on my parts car to show how long it is before being shortened. The rubber bumper was removed prior to this picture, but on my '84 the rubber bumper was reinstalled after the cone had been welded back on. The metal cones are now 4.5" long.


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tesmith66
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Report this Post11-01-2013 07:11 AM Click Here to See the Profile for tesmith66Send a Private Message to tesmith66Edit/Delete MessageReply w/QuoteDirect Link to This Post
The hardest part is cutting them straight. I placed a piece of PVC pipe over the cone as a guide to mark my first cut. I also took the crossmember off of the car so I didn't have to cut and weld while standing on my head.

Tip- leave the bumpers on when you make the first cut, then use a lot of silicone spray lube and carefully push the bumper out from the inside (I used a blunt screwdriver to push the rubber back into the hole). After welding you can lube up the bumper and pop it back in.

Tip #2- While the crossmember is out of the car, you can clean it up, weld the upper crossmember tubes real good (they aren't welded too good and tend to break loose over time) and paint it.

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1986 SE Aero coupe.

3.4 DOHC swap is complete and running, now just have to finish the rest of the car...

[This message has been edited by tesmith66 (edited 11-01-2013).]

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Brucepts
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Report this Post11-01-2013 07:13 AM Click Here to See the Profile for BruceptsClick Here to visit Brucepts's HomePageClick Here to Email BruceptsSend a Private Message to BruceptsEdit/Delete MessageReply w/QuoteDirect Link to This Post
I lowered my 85GT earlier this year and it was an interesting ride for a few days, I then reset my front sway bar links so the bar ends were parallel to the road when the car was sitting on the tires on the ground and have not had an issue with the bump stops hitting. Prior to my "reset" it was hitting no make that slamming but after the "reset" it rides so much better!

I ended up with 5/8" spacers and the bolts if I recall were 5-1/2" long, I also used poly on the links, just my observation for what it's worth . . .

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Khw
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Report this Post11-01-2013 08:44 AM Click Here to See the Profile for KhwClick Here to Email KhwSend a Private Message to KhwEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yeah pretty much what patrick said. It all depends on how much taper your looking at. I mean a taper that's 5o off of veritcle isn't going to be much of a difference over 3/4", unlike a taper that's say 75o off of veritcle. Also, the gap, if there is even all that much of one, will be filled with weld.
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