Anyone Modify 87-88 V6 Dog Bone For Poly Bushings? (Page 1/3)
reinhart MAY 10, 05:19 PM
Surprisingly I couldn't find anything in the archives of someone doing this. I was able to get a set of poly bushings out of a 4 cylinder dogbone and was going to install in my 88 V6. I know about the internal ridges and figured I'd just grind them down. I easily cut them out with a circle saw but then realized that the OD of the 87-88 is still larger than the 85-86 V6 or 4 cyl.

So the ID is 1-7/8" for the 87-88 vs 1-3/4" for all the other dog bones. I couldn't find a poly bushing of that OD.

A few thoughts on this:
1) Find a metal sleeve/pipe with OD = 1-7/8 and ID = 1-3/4"
2) Make custom poly bushings using liquid urethane and a mold.

Anyone successfully do this 87-88 V6 stock dogbone poly conversion before? How did you do it?
fishsticks MAY 10, 05:27 PM
I don't have an answer to your exact question, but that seems like a ton of work.

Do you have a local steel yard? I'm positive they will have the properly sized tube for those bushings. Just make your own dog bone. It's very likely they will have short lengths in the remnant section that you can get for nearly nothing.
skywurz MAY 10, 06:25 PM
Not sure how it was done but my 88 has a factory dog bone with poly pressed in. I have a v6 TFS one around here somewhere I'm probably going to swap in, instead.
Patrick MAY 10, 07:32 PM

quote
Originally posted by reinhart:

Anyone Modify 87-88 V6 Dog Bone For Poly Bushings?

Surprisingly I couldn't find anything in the archives of someone doing this.



Let's rebuild an 87 dog-bone with pictures

[This message has been edited by Patrick (edited 05-10-2021).]

fieroguru MAY 10, 08:19 PM
From this thread:
https://www.fiero.nl/forum/...160323-2-124009.html


quote
Originally posted by fieroguru:
I can't link to ebay from this computer, but having just purchased some poly bushings listed for the stock 88 2.5 dogbone - buyer beware.

The inside surface of the stock dogbone is not a uniform circular tube that you can just slide a normal round poly bushing into. The inner surface is tapered and it also has an inner lip. To get mine to fit, I had to put them in the lathe and turn the needed taper into the bushings. Once I did that, I was able to install them.
reinhart MAY 11, 06:53 AM
Thanks Patrick. I noticed he didn't tackle the slightly larger diameter issue.


quote
Originally posted by Patrick:

Let's rebuild an 87 dog-bone with pictures
reinhart MAY 11, 07:09 AM

quote
Originally posted by fishsticks:

I don't have an answer to your exact question, but that seems like a ton of work.

Do you have a local steel yard? I'm positive they will have the properly sized tube for those bushings. Just make your own dog bone. It's very likely they will have short lengths in the remnant section that you can get for nearly nothing.



If by a ton of work, you mean 5 minutes then yes. I have about 5 min invested in this project so far. Two cuts to get the bushings out and two hole cuts to get the cylinders even. In fairness, I did spend some time looking around the web for a pipe or liquid urethane but I've been interested in the idea of liquid urethane for a while now anyway.

Just found an exhaust pipe on egay that's 1-7/8 OD and 1-3/4 ID. It's 3-1/2" long so more than enough material to cut 2 x 1.5" sections. Seems like that is the easier route at this point. Probably just coat the metals with epoxy so it doesn't try to move on me and that will hold the sleeves in place.
Patrick MAY 11, 05:25 PM

quote
Originally posted by reinhart:

I noticed he didn't tackle the slightly larger diameter issue.



I don't know if was due to the particular '87 dogbone used or to the poly bushings chosen, but it appeared he didn't need to.
Dennis LaGrua MAY 11, 06:25 PM
Start with an 85-86 V6 dogbone, cut out the rubber bushing, clean and paint it, insert the Prothane bushings (that are a direct fit) -done.

------------------
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"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

reinhart MAY 11, 08:14 PM

quote
Originally posted by Patrick:

I don't know if was due to the particular '87 dogbone used or to the poly bushings chosen, but it appeared he didn't need to.



Did you read the thread you linked?