Saginaw, etc. shifter arm geometry.

Doober

Moderator
Jun 2, 2003
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Catalina, AZ
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I'd like to undertake a project to shorten the throw of the stock style shifter, but I'm curious about the geometry of things. I believe the arms on the bottom of the shifter itself can be lengthened, essentially shortening the distance the stick itself has to travel - similar to a short-throw shifter on a rail-type transmission, where the pivot point is basically moved up, shortening the stick/lengthening the bottom side, which shortens the distance the shifter ball itself has to travel - my only concern is the arc. I don't believe it would really cause a major issue because the difference in length is quite low, I'm just wondering what anyone else may think.

I believe a piece of steel channeled around the original arms with a bolt through the original pivot hole for the rod would suffice, possibly shortening the shifter fork arms as well, so geometry would stay the same. I wouldn't bother with the reverse arms, being unnecessary.
 

t5montecarlo

MalibuRacing Junkie
Oct 21, 2007
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Lengthening the shifter arms would likely be sufficient. You can lengthen them as much as you need without also having to shorten the transmission fork arms. You should do some geometry math first, beginning with your known: how much you want the handle to move to engage each gear. The rest of the geometry can be calculated.

You would not need to use a channel steel. Once you determine how much longer each arm should be you can just weld flat stock to each arm to maintain the same distance from each arm so you can still assemble/disassemble the linkage.

You will not have to shorten the handle as well. A shorter handle is not very comfortable.
 

Doober

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Thread starter
Jun 2, 2003
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Catalina, AZ
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That was my thinking on the handle. I'm still using an old shaft I cut and drilled from a junker Mr. Gasket shifter. The stick I plan on using I believe moves the ball over another 1/2" or so more than the one Hurst calls for a G-Body, if it sits where I believe it will, it should be quite comfortable. The shifter arm in my Fiero is a 'short throw' unit that is maybe half the height of the original, a couple places sell their own variety... throws are very short, but also somewhat stiff, not near as stiff as a v6/5-speed '05 Mustang I've driven on occasion though.

I prefer the channel route on the arms only because I don't want to weld on them. I already did a slight 'mod' my last trip to MI using the main bushing/bolt area. There was play in the left/right movement of the stick, maybe .030-.050, I didn't like it. I tightened the bolt to what I felt was the safe limit of the nut welded on the bracket, and there was still play. I took a washer that was just a barely larger o.d. than the lock washer for the bolt (5/8" or metric equivalent), and reamed it out to fit around the bushing the shifter arm pivots on. I then very carefully thinned it out (used what I had on hand, it was late and a suitable washer can probably be bought from a hardware store, possibly a bushing type washer?). After sliding the bushing out far enough for this thin washer to sit on, I put everything back together and snugged everything down after greasing the pivot area liberally. Now there is zero play, and I tightened the bolt until there is just a hair of resistance. I also put a set of steel 'pit pack' bushings in, the nylon ones were atrocious compared to how they should've been, and they had maybe a couple thousand miles on them.
 

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