Short shifter vs. standard in an SC
 

Hey guys,
I was reading an article the other day about the G-50 vs. the 915 tranny and the author is summarizing about the ill deserved clunky reputation of the 915.
he goes on to say that the 915, is a very dependable and durable tranny if treated gently. He also states that SWEPCO lubricant is the absolute must for improving shifting in the 915, and that one of the worst things you can do to it is to add a short shifter because it will cause premature wear to the synchros and provide a much rougher shift. I have my 78 SC down to a shell at the moment and I thought it might be a good time to source a G-50. If however you guys don't deem it a necessary upgrade I'll just keep my money and the 915.

Can anyone who has done this conversion comment on your experience. or if you're running a 915 with standard throw shifter with SWEPCO, how has your experience been.
Much appreciated,
-Norm

Bump...

Anyone?

I have a 915, and put in a short shifter. The short shifter made shifting much easier. I also tried Swepco, but I only used it for a short time. I did not feel it made any difference whatsoever. I use some German lube in there now; the name escapes me at the moment. In any case, my 915 is a POS, and needs a rebuild over the winter. It doesn't help that I'm kind of rough on it.
Pat

Swepco made a noticeable difference in shifting on my car. It did not make it shift like a modern transmission. The short shifter does improve shifting but if you rush the shifting with the short shifter I do think it will shorten the life of the transmission over stock. I get a little grind when shifting fast with the short shifter when going to 3rd gear.

Thanks for the feedback guys, keep em coming!

I ve got a short shift kit and 915 in my 78 SC. I don't think I could go back to the long throws of the old shift set up. Going on 3 years and lots of spirited driving in the mountains and I am not having any trouble. Not sure if Swepco is making any real difference or not. Maybe I am just the lucky one.

Good luck!

S

I don't know about short shift kits on a 915, but swepco DID make a lot of difference in my gearbox. I guess it depends what your issues are to begin with... Best thing I've done to smooth my shifts, in order:


1) Shift slower and lear heel and toe
2) swepco201
3) a Seine spring loaded shift gate

Ironically, I used to own a 73.5 911T with a 915 with several hunded-thousand miles (presumably, on a 5 digit odometer). That car's gearbox was the sweetest 915 ever, it shifted better than a modern honda for pete's sake, smooth, butter soft, no slop at all. So now I KNOW those boxes can be made to work well. It's funny that my 83's 915 is nowhere near as good as that 73's box, with less miles... But it's a good gearbox once you get to know it, and assuming it's not damaged.

The G-50 uses Borg-Warner synchros.
The 915 uses Porsche synchros (their famed design).

That is the biggest difference. The synchros have a different feel to them, but I would NOT say that one feels better than the other IFF they are both in excellent working condition.

Each has certain advantages and certain dis-advantages...

You should read Aichle's book on the 911 - he has some comparisons in there.

I replaced the syncros in my 915. Then I put in new bushings and adjusted everything perfectly. And I still hated that damn thing. I was tempted to spring for a G50 conversion... Then Tyson put in a WEVO shifter. I love my 915 now. Shifting is precise and predictable.

Your 915's new best friend;

http://forums.pelicanparts.com/uploa...1188948297.jpg

Shifting quickly is all about timing. Short shifters help many people get the shift done quickly enough. (the rpm does not have to drop much for a perfectly matched shift) IMO the shorter the shift lever throw is, the less feel the driver has for what the synchros are doing.

Note: I have an OE style short-shifter. I briefly had the WEVO like Moses' picture. --It felt like it using a battering ram into the gears. . . but w/ a very short throw. (many like that feeling)

I have both. My 3.2 cab has the OEm short shift and the 930 has the WEVO. I really like the WEVO as it is so solid and precise!

I gotta wonder if there was a problem somewhere else. My shifting style is very soft. I never jam a shift lever. I use very little force. Maybe my WEVO shifter works so well because every thing else is adjusted nicely and I have fresh syncros and bushings.

I didn't mean to say there was a problem. Just that you really feel the weight of the (billet) chunk of aluminum. You really notice when you go back to the OE shifter with the plastic knob. To that end, I understand that WEVO gives the option of a more OE type lever.

".....IMO the shorter the shift lever throw is, the less feel the driver has for what the synchros are doing. ....."

If you think about it, a short shift lever provides less leverage (the fulcrum point moves upward), thus driver effort is higher and able to better feel the shift being completed. A longer shift lever ratio provides more leverage to move the parts into mesh, thus shifting is easier at the expense of increased throw distance.

There's a happy medium between shifting effort and feel. In this regard, everyone's MMV (mileage may vary). Some SS kits go too far overboard with reduced throw at the expense of increase shifting effort. Some drivers don't mind the increased shifting effort in exchange for slightly shorter throws, and some prefer the feel of the factory shifter just fine.

The three bears had their preferences down pat, but Goldilocks had to go through a process to discover her personal comfort level. Pcar owners are no different, but we're fortunate to have options to consider w/o the stress she finally endured. Silly girl. Didn't she notice the family pictures?

Sherwood

Don't go with the G50 in a car built for a 915 unless you want huge headaches fitting the transmission to the car, which involves replacing the torsion bar tube, iirc. Ask BeauBlues about it.

oh Really !?! So then, if you had to read Braille, you hit it quick and hard, to get the best feel?

I totally agree that there is a balance there, between feel and shortening the throw. In this case it's an ergonomics question of force vs distance. ....if Braille bumps are too close together, you can't discern the pattern . ...too far apart, and it takes too long to read. I just think that the 915 operator benefits from the light touch side of the spectrum. In my experience, learning from the feedback is helpful for learning clean shifting.

Of course many others don't care what the 915 is telling them. I'm not sure why they don't just get an auto . . a tiptronic, and be done with all this "manual shifting" nonsense.

I love my 915 and would not change it for a G50. Granted my syncros seems to still be in relatively good shape. I use SWEPCO but the difference was marginal. Some report huge improvements. Possibly depending on how much wear on the box when changing lube.

Very important to have fresh shift bushings and a correctly set up coupling as well.

IF I wanted a G50, I would probably buy a 87-89 car instead of the hassle of changing which involves pretty much labor and money.