How many times have you had to adjust your neutral gate?
Is this your first A833?
Does the trans grind when selecting reverse?
You and your trans have multiple problems.
The cover is fine
The checks;
1) The first thing you need to do is check your clutch departure. and
2) the Second thing is to check your clutch disc for dragging. and
3) the Third thing is to make 100% sure that the external shift levers are NOT movlng on the studs.
4) the Fourth thing is to make sure that the 1-2 lever moves freely with the 1-2 shift-rod disconnected
5) After that, if you have installed synthetic oil of any kind; get it out! Install a 50/50 mix of Dextron-II and 85/90 EP gear oil WITHOUT any friction-modifier in it; any brands.
the Explanations;
1) If this is your first A833,
If yes, then;
Those gears inside the box are big and heavy for a Passenger-car trans.
But thick gear oil will often slow them down too quickly, while thin oil tends to not slow them down fast enough. You need to learn your best window of catching a gear, which changes with whatever rpm the engine has run up to. The synchros CANNOT be expected to do all the work, unless you are granny shifting and the trans is in perfect working condition. If you miss the window on an upshift/downshift, you will have to readjust the rpm to get back to it.
Meanwhile, if the clutch disc is dragging on the PP, with the pedal depressed, then it will be doing about whatever rpm that the engine is. If you have allowed the rpm to return to idle, whereas the shift window is 3000rpm; then the synchros will never be able to cover that.... and if you force it, it will just grind.
If simultaneously the shift-levers have moved, then you neutral gate goes away, adding more frustration to the experience.
And finally;
there is an interlock inside the trans on the reverse lever, that works in conjunction with the one, on the 1-2 lever, to prevent accidental simultaneous engagement of both reverse and first. Those two moving interlocks are extremely close together, and if the cover is not installed exactly right, then they can rub on each other, causing shifting issues.
Fixingchit
Ok then, IMO, lets look at things beginning with the most likely. Except, if this is your first A833; then you gotta learn to shift this brute; See Note-1
If I had this problem, here's what I would do.
1) I would get the back wheels off the ground, then with the engine off and the trans in Neutral, I would shimmy under there and see how much power it takes for me to spin that doggone driveshaft........ which should be "very little". If it takes unusually much power to turn the driveshaft, find out why and fix it! go to step-4
2) I would start her up, with the box in neutral, then make sure my 340 idles at a decently low and smooth rpm, say 700/800.
3) Then I would put it in Second, and let the wheels come up to speed, then put it into neutral and time how long it takes for the wheels to stop.
Next, I would again put it into Second and let the wheels come up to speed; But this time, I would depress the clutch pedal and again time how long it takes for the wheels to stop Turning.
4) if there is a huge disparity, it is because the clutch is dragging on the PP, and we have to find out why and fix it!, lol.
With the engine off, Have a helper put the trans in Direct, and depress the pedal, while you go turn the driveshaft. At this time the Driveshaft will be spinning the mainshaft, and thru the 3-4 synchro the input gear which will spin the disc, because the clutch pedal is depressed. This should only take a small amount of extra effort compared to spinning the driveshaft in neutral. If it takes a lot of effort, then the disc is dragging.
From here on out, I assume that you have a factory BellHouse.
The first check is for adequate departure. .080 should be plenty, make sure you got it.
If you have at least that much, then the next check is for a warped disc. You will need TWO helpers; Put the trans in Direct and the engine off. Have one helper depress the clutch pedal, and the other go spin the driveshaft, while you watch, thru a window in the PP, the disc going round and round. Ideally, it will not be touching either the PP nor the Flywheel. I have yet to observe that.
More often, I see the disc bouncing off the Flywheel, which if that is all it's doing, that's fine. But what you don't want to see is the Disc wobbling around and bouncing from side to side. If you see that, there is likely the biggest part of the problem. They can't be unbent so, she'll have to be replaced.
Now, if the disc is rubbing just a little, more departure may be an option ......... cuz as you get better at your shift-timing, it will cease to be an issue, unless it gtinds when selecting reverse.
Note-1
Choose a shift rpm, Since you have an Overdrive, I'll assume your rear gears are about 3.91s. Its not real important but it makes for easy figuring. As I recall the ratios in that box are 3.09-1.67-1.00-.78..
This makes the splits; .54-.60-.78, which means that whatever you rev the engine to, the rpm will fall to one of those percents, at the shift.
So lets say you chose 2800. I like 2800 cuz my 360 sounds real nice at 2800. Ok so then, buzzing up to 2800 will get you 18.6mph (with 27"tires). Then, going into Second from 2800 in First, the rpm should drop to 2800 x.54=
[email protected] mph; that's a lotta lotta drop. Your 1-2 synchro has to now match the roadspeed of 18.6 mph to 1512 rpm. That synchro has the job of speeding up or slowing down EVERYTHING in that box that is spinning, that is NOT physically attached to the mainshaft which is being driven by the driveshaft.
If you could, at exactly 18.6 mph, bring the rpm down to exactly 1512 rpm, the slider would jump right into Second.
If the clutch disc is freely turning with the clutch pedal depressed, and the oil in the trans doing it's job of slowing the spinning parts down, then the synchronizer should be able to deal with a couple of hundred rpm of mismatch..../ assuming the brass-ring and the brake cone are functional.
But
if the vehicle speed has slowed to less than 18.6mph, or if the engine has slowed to less than 1512 rpm, or if the clutch disc is dragging on the PP which is running at Engine rpm, then, the synchro assembly may not be able to do it's job of synchronizing.
Furthermore
If the brass-ring is bent, or the brake cone is too slippery, or the strut energizer springs are weak, then the synchronizer is not gonna be very efficient at it's job.
So your job, as both tuner and operator, is to try and match the rpm to the roadspeed and then slam that shifter hard-over. lol. The closer to perfection that you can get, the easier and more quickly, the synchronizer can do it's job.
So what are the secrets?
Well firstly, if you left the parking brake on, then the car will slow down during the shift. Or if the discs are dragging, or the shoes, or anything else is dragging, same answer. Fix that first.
Second, if your 340 goes from 2800 to idle, faster than you can shift, something is wrong...... or
If your 340 takes longer to come down to 1512 rpm, from 2800, and you are hammering on the shifter trying to get it in there, something is wrong. Fix it.
Ok back to the main post above^
Ok so, I think that's about it ...
Supper time!
