915 Shifting Issue- Help Please
 

I just got my car back from about two months in the shop to do a coilover suspension and a rsr sway install. I had them adjust the shift linkage. The trans has low mileage and new Swepco.

It is hard to go from 5th to 4th and there is a little grinding also. I am shifting slowly and not ramming it back. Any thoughts?javascript:checklength(document.vbform);

So... TAKE it back to the shop and tell them to fix it.

I will but I need to understand if it is a linkage adjustment issue or is it syncros or some other issue. There is a lot of experience here that can probably give me a little insight.

Is it hard to shift, or slow to shift? (linkage vs syncro's)

It is hard getting it into 4th. Hard to shift. All other gears are smooth

sounds like a syncro.

It is a lot of work for the syncro to down-shift into 4th. (or any down-shift) ...esp when the rpm drops far below the needed rev's. (shifting slowly w/o rev matching)

If it finds the gears going up, but not down most likely synchros. If it can't find the gears either direction, probably shifter adjustment, but I'm no expert.

How did it shift before you had them adjust it, better or worse?

My other car is a 997 Carrera S. I had a GT3 and an 87 G50 car before this. I found the shifting to be very imprecise. We just installed the Seine kit, but that should not be causing this issue. It never feels like I am solidly in 4th. When I go to neutral and pull it down into 4th is when I get the grinding.

possibly you're nicking reverse on the way from 5th to 4th. couple adjustment. try kendall 80/90 instead of the swepco for an easier shift through all the gears.

Do you double clutch on the way down? This will help the synchros.

Nicking reverse is exactly what it feels like.

What kind of coupler do you have in there now, maybe the shop didn't take the time to adjust properly which can take a few drives/adjustments to get just right? Took me about an hour to adjust mine the last time. I now use a hose clamp to mark front to back adjustments. left to right is tricky.

if you have a short shifter, then getting the adjustment correct takes more fiddling around. no slop in any of the bushings?

This is exactly what happened to me after I installed my short shifter. After some more adjusting the coupler it took care of the problem.