Help - Bad shifting
 

Took the 914/4 race car to Topeka for a DE to do test/tune on it. Managed to not blow the engine, but not for lack of missed shifts. Lots of 4-3 and get 1st, with some 3-4 and get 2nd to keep me off balance.

1972 car, recently rebuilt tranny ($2,650!!!), replaced shift bushings, replaced motor mounts and tranny mounts, added shift lock-out springs.

I've spent way more than what should be required to fix this. The obvious answer is convert to side-shifter, but does anyone have any other suggestions? Throwing new parts at it has gotten expensive.

Thanks!

Re: Help - Bad shifting
 

I've driven both a tail-shifter and a side-shifter. And, compared to most modern day technology, the side-shifter still sucks. However, it is so, so much better than a tail-shifter. Convert to a side-shifter and you will be upgrading to "merely horrible".

Paul

Not knowing your racing experience and to save money on a conversion, seat time and getting to know the car will help immensely.

In the heat of battle, it is hard to remember that "speedshifts" only occur in the movies and with multi-lever drag racers. I adopted the "two finger and thumb" grip on the lever, rather than the gripped fist - saved a lot of trannys as I wasn't shoving it into gear.

Just an opinion, not a hard and fast rule.

BUT, a side shifter does shift much better than a "wish stick" (wish I knew what gear I was in) tailshifter.

Good Luck!!!

Well put Ron! Much more eloquent than my attempt.

ask the outfit that rebuilt your trans if they replaced the little rolled pin inside the rear of the trans case part 11, fig5.21, pg 86 of the haynes manual.the weltmeister short sift kit will help.

2500 beans, ouch. i take it they took it out and put it back in for that.

paul, whats with the box with the blinking line and search under your name?

I had a tailshifter in my track car also. I don't care how right you have it, it still will not hold up to consistently shift under race conditions. I finally had to face the music and convert to a sideshifter. At least you can convert that $2600 tailshifter to a side shifter.

Dave, maybe you'll ultimately have to convert to a side shifter, but here are a few things to try. I don't have a tail shifter, but I've had good luck tightening up my side shifter and the philosophy should be similar.

Your enemies are slop or "play" of the shift rod components in their bushings, flex of the shift rod (it's NOT supposed to be a torsion bar), flex of the mounts that hold the bushings that hold the shift linkage, and the potential of the tranny swimming around on its mounts as you accelerate / decelerate. Sounds like you took care of the motor and tranny mounts. Did you replace the tranny mounts with 914 stock, or did you use the (cheaper AND firmer) 911 engine mounts? Every incremental amount of stiffness helps.

Like you, I went through and replaced bushings. Even after new (nylon) bushings, though, my shift rod rattled around in its new bushings, either due to wear on the rod (doubt it) or sloppy bushings (bingo). You really don't want ANY free movement ("rattle"), whether it's a component rattling around in the bushing, or the bushing rattling around in its mount. If your new bushings have some slop, you can wrap the rod or the bushing O.D. with tape until it's tight. Metal muffler tape will probably last the longest. If one of those ball thingies is rattling around it a cup bushing, try another bushing. Pelican sells bronze bushings that may be tighter than the plastic ones, call them and ask. Also, make sure you got ALL the bushings, I missed the little cup thingy at the base of the shifter itself the first time around.

Check any brackets holding bushings and make sure they are mounted tightly, and are not cracked. If they flex during the shift, that adds slop to the equation. If you can think of a way to beef them up, do it. That L shaped bracket just on the back of the shifter has probably seen a LOT of torque from 30 years of frustrated drivers.

You might want to call Patrick Motorsports and talk your situation over, they have a thick replacement shifter bar with a true U-joint and bronze bushing that is very tight. The one I know about is for a side shifter, but they might have a tail shift solution too.

Granted, these are all band-aids, but try the cheap ideas first, you can always fork over the big bucks later.

Thanks Paul, my ego just got inflated!

On the way home, I thought of something I should have added:

Convert the tail shifter to a side shifter. With $3K into a trans, another couple of hundred to convert it to sideshifter is cheap.

You will need:

1. Complete shift mechanism (shifter, front and rear rods) from a sideshifter.
2. Late engine mount bar, mounts and engine brackets
3. Conversion bushing for firewall (Pelican Parts)

And for the tranny (not totally sure of all parts):
1. Side shift selector plate (place already for it on the tailshifter)
2. Might require different shifter shafts (shorter)
3. Side shifter end piece (but I also heard you can leave the tailshifter end piece on and plug the selector boss).

Nuff said!

Thanks!
 

Thanks a ton - you guys rock!

I've had the car ten years and done numerous DEs, both in it and other cars. Of course, it's always easier to blame the equipment... ;-) Extreme concentration and focus helped some, but there were still plenty of 4-3 get 1st.

My first race will be in June so I am willing to spend the $$$ to convert if necessary. It's cheap money relative to a zinged engine. I was willing to live with a nasty shifter, as in long throws, hard to find gears when stopped, balky first (even after spending big $$$) but I'm having difficulty sleeping given the risk of blowing the engine. I will try your suggestions, and convert if necessary.

There's always a silver cloud - I found that I can use fourth instead of third through turns 7-8, and delay my shift from fourth to third to 15 instead of 14 (where I'm shifting in a straight line and have better luck). So two new options through corners. Plus, I learned just how torquey my 2.0l is, and how strong it will pull at 3000. I was probably revving too much before, trying to use horsepower when I should shift sooner and use torque.

Thanks again!