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Joined: Wed Oct 15, 2014 9:48 am
PostPosted: Tue Jul 12, 2016 12:30 am
Well haven't been doing much grinding but have missed 5th a couple of times and ............ well we know what happens then. Luckily the over revs haven't been over 8000.

My shift linkage like a lot of the cars is really lose. Can anyone tell me how bad a job it is to pull it out of the car and replace the joints with apex joints? I see a couple of pieces that aren't immediately obvious as to how they come apart (heim combo under sift knob and piece just behind it).

Almost looks like it pulls out through the front and not out the back? How bad is it to adjust once it's back in the car?

Just looking for some advice from someone that has been there before I start down this path as the next event isn't too far away. Unfortunately I need 5th for that event.
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Joined: Mon Dec 05, 2011 10:03 am
Location: Greenwich, Connecticut
Chassis:
860
PostPosted: Tue Jul 12, 2016 9:31 am
I had trouble getting it into and popping out of 5th after my GEN3 conversion and had overlooked making sure the bolt that connects the linkage to the transmission shift rod was tight enough. Be sure that's pretty snug, about 55 foot-pounds of torque. Once I had that tightened haven't had an issue with staying in 5th. Check that out first.

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Location: Monument, CO
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540
PostPosted: Tue Jul 12, 2016 10:24 am
The key to removing the shift linkage without disassembling the car is extracting the roll pin (also called spring pins or C pins) which holds the shifting shaft (which goes to the tranny) to the shift linkage/joint next to the driver’s right hip. The pin has a yellow arrow pointing at it in the below picture. Sometime you can just push or pull the pin out with plyers, but chances are you will have to use the right size pin punch and tap it out with a hammer. This usually requires that you build some support under the joint (blocks of wood shimmed up from the floor pan and a block of wood under the floor pan to the ground). The rest is just disassembly, some machining of an adapter and reassembly. It is a pain, but you will be rewarded with a tight shifter (please hold the guffaws).

Let me know if you have further questions.

DaveP
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shifter 1b small.jpg
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Needs a Life!!!
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Location: Texas
Chassis:
821
PostPosted: Tue Jul 12, 2016 11:38 am
I've had an issue with the car staying in 5th since the G3 conversion...not entirely sure it has been resolved as it only slips out when you make the 4-5 shift at redline or close, and have not been back to a track that uses 5th since working with Mikey D on the issue. Here is another potential problem:
Image

Check the length of the bolt that attaches the linkage to the transmission, it can hit the frame in 5th, depending on the frame and exactly where the trans is positioned. Simply trimming the bolt in length will provide clearance.

Ready to Write a Book
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Joined: Wed Oct 15, 2014 9:48 am
PostPosted: Tue Jul 12, 2016 2:52 pm
Thanks for the info. Never had to deal with the roll/c pins before. It makes a little more sense now.

It's not popping out of 5th, just so sloppy that it's questionable where 5th even is. I can see the play in both u-joints and some in the heim joint. My car is from the early 90's and I doubt any of this has ever been touched.

Sorta reminds me of my old 71 Porsche 914 before I replaced all the bushings in the shift linkage.

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PostPosted: Tue Jul 12, 2016 7:26 pm
Steve, looking at your picture it reminds me of a problem we had, which is just the opposite of what you have suggested with the linkage bolt. In 2006 I bought a brand new car and assembled it myself. When I installed the linkage bolt, you are pointing out in the picture, I installed it in the same up word direction as your picture indicates. In our first race with the car, the rear bar clevis came in contact with the bolt, while going over a rumble strip. If you look at the bolt in your picture, you will note that that it extends more upward than if the flat end of the bolt was on top rather than on the bottom.

It slightly bent the linkage rod, which sticks out of the trany. It stuck in 3rd gear about half way into the race. Discussed this with Beau at Elite Autosports, and found this is a rather common problem. So after one race on the car, out goes the engine and trany and the trany shipped to Beau for a repair, replacing the rod.

So no matter which direction you put the linkage bolt in, you have to check two things. First is there proper clearance, so that the top of the bolt doesn't hit the rear bar clevis under compression. 2nd as you indicated, that the bottom of the bolt has adequate clearance to the lower control arm bolt through out all the different gears. The position of the clevis, soft vs hard setting, also affects the clearance needed for the bolt. Older cars can also have bent mounts which can contribute to the problem as the engine might shift.

One way you can check to see if the bottom of the clevis has come in contact with the bolt on any car is to check to see if the clevis has marks on the bottom. This was easy for me to do, as the car was new. The one near the linkage had a rather deep mark on it and the right one did not. For me installing the bolt in a downward direction took care of the problem, but I still need to monitor the lower bolt as it extends further toward the ground.

Pat

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