revs die very quickly
#1
revs die very quickly
After driving my car for a couple days, I've started making a list of the maintenance items. Chief among them is to bleed/adjust the clutch (I'm pretty sure it's not disengaging fully), renew the shifter cup and coupler, and do some serious brake maintenance including rebuilding calipers (they are dragging slightly), replace lines (5 yr old ss lines), new pads and a full flush.
One thing I am having trouble with is how fast the revs drop during a shift. Unless I power shift, which I'm not willing to do, it's almost impossible to shift to the next gear before the revs drop all the way to idle. I don't remember my last 928 doing this. It's almost like the car has a very light flywheel, and combined with the difficult shifting right now, makes it tough to drive. I mentioned that I thought the clutch might not always fully disengage because once in a while it's very hard to get out of gear, much less get into the next one. Could this cause the revs to drop so fast? I would think it would stall if that's the case, but it never stalls, just will drop to idle in a split second - a perfect idle I might add.
One thing I am having trouble with is how fast the revs drop during a shift. Unless I power shift, which I'm not willing to do, it's almost impossible to shift to the next gear before the revs drop all the way to idle. I don't remember my last 928 doing this. It's almost like the car has a very light flywheel, and combined with the difficult shifting right now, makes it tough to drive. I mentioned that I thought the clutch might not always fully disengage because once in a while it's very hard to get out of gear, much less get into the next one. Could this cause the revs to drop so fast? I would think it would stall if that's the case, but it never stalls, just will drop to idle in a split second - a perfect idle I might add.
#2
Hey Mark,
The revs in my car drop very quickly too. (But they also go back up really fast). I don't think there's anything wrong, I think it's just a case of getting used to it. Many newer cars stay up at the higher revs long enough to make a smooth transition. I've gotten used to 'rev matching' (again, as that's how I learned to drive years ago). Mine is an '85, so I don't know if it's comparable, I'm just giving my experience.
With respect to the couplings: not directly related, but another wear item in addition to the forward shift ball cup and the rear shift coupling is the release arm ball cup. I'm not sure what it looks like in an '83, (intake-wise) but at the top of the bell housing at the rear of the engine you'll see the top of the release arm. On mine, the cup or bushing that goes inside the end of that arm was completely gone and made the clutch action inconsistent. It's a cheap part, but if you're not replacing the clutch at the same time, I'm not sure how to replace it. You might want to do some searches on this. If the other two shift wear items are worn out, this one probably is too.
The revs in my car drop very quickly too. (But they also go back up really fast). I don't think there's anything wrong, I think it's just a case of getting used to it. Many newer cars stay up at the higher revs long enough to make a smooth transition. I've gotten used to 'rev matching' (again, as that's how I learned to drive years ago). Mine is an '85, so I don't know if it's comparable, I'm just giving my experience.
With respect to the couplings: not directly related, but another wear item in addition to the forward shift ball cup and the rear shift coupling is the release arm ball cup. I'm not sure what it looks like in an '83, (intake-wise) but at the top of the bell housing at the rear of the engine you'll see the top of the release arm. On mine, the cup or bushing that goes inside the end of that arm was completely gone and made the clutch action inconsistent. It's a cheap part, but if you're not replacing the clutch at the same time, I'm not sure how to replace it. You might want to do some searches on this. If the other two shift wear items are worn out, this one probably is too.
#3
Thanks Mike. I'm so used to heel/toe that I just drive like that, every single shift. So I automatically rev-match during downshifts, but I find myself having to do it on upshifts now too, which is not as clean. I suppose that once I get the linkage straightened out and bleed/flush and adjust the clutch, it will be much easier to shift and the revs won't be as much of an issue.
#4
Without powershifting I don't think the revs should drop so quickly that you have to rev match changing up. (I don't have to in the SE or GT unless the transmission is really really cold - not often in OZ)
Normally the revs have dropped to about the correct point by the time I am ready to bring the clutch up in the new gear.
If the clutch was dragging then while still in the lower gear as you change out of it, it would tend to keep the revs up .
I'ld guess that you are spending too much time stirring porridge - time for a shifter linkage makeover.
Normally the revs have dropped to about the correct point by the time I am ready to bring the clutch up in the new gear.
If the clutch was dragging then while still in the lower gear as you change out of it, it would tend to keep the revs up .
I'ld guess that you are spending too much time stirring porridge - time for a shifter linkage makeover.
#5
That's the best analogy I've heard. And I think you're right. I'm putting together all the parts now and will renew everything stem to stern. Hopefully that will make the difference!