floor pans?

kasbatts

kasbatts

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Hey guys,


Do the Auto cars and the Manual transmission cars have the same floor pan?

My car used to be an Auto, but now manual.

The reason I ask is I am having trouble with getting my CR 5 speed up high enough in the tunnel to get the prop shaft to run straight from the gearbox to the diff, as it sits at the moment I have the gearbox as high as possible in the tunnel (just 5mm clearance at the closest point) I have had to lower the center hanger bearing 30mm to relieve any bending of the rubber donut joint as a result of pushing the hanger bearing up to its standard position in the tunnel.

A flow on effect of me lowering the center bearing now is a loud knocking from the bearing when a lot of power is applied (standing start hard acceleration etc) I'm guessing its being flapped around quite a bit on the rubber diaphragm within the outer shell of the bearing assembly when this happens?

This weekend we are going to try and get the gearbox up higher in the tunnel and get the drive shaft running straighter, I think we will have to "massage" the tunnel a little here and there with a hammer to get clearance in places.

I have mentioned this problem before in another post but got no feed back from anyone? It just seems strange that I'm the only one that's had this trouble??

Anyone else???

Steve
 
Steve: I think this happens when you have the center bearing upside down. Since the bearing "holder" mount can be installed both ways, and it fits the wrong way, it's hard to see what's not right. BTDT.
 
Steve, some guys over here with 5 speed have remedied the problem ( I believe) with some sort of transmission support bracket ...can't say I took much notice as I 'm retaining 4 speed but will investigate further . Cheers, Simon
 
Steve, I phoned Mark Baxter ( "Nice Colour ") and he suggested you Google "5 speed conversion cs "...there is an article by Carl Nelson listed . I'm just the messenger so sorry if a bit vague but Mark mentioned some sort of support bracket modification and apparently if you are using tailshaft from auto, then that has to be modified too. Anyway , see how you go and PM me if you think it's easier to liaise direct with Mark ( unless he jumps on the Forum when he gets home ) Cheers, Simon
 
Ok, read and under stood, it's saying any pre 82 box is going to fit, therefore post 82 won't?
Maybe my box is post 82? I don't know, I just bought it of a local guy who is the go to guy for the coupe, figured he would know if it was going to fit.

Anyway, will have a crack at getting it up into the tunnel further this weekend
 
Spent the day on the car today, came to the conclusion that the problem with getting the cr 5 speed far enough up into the tunnel is a lump that sticks out on the RH side at the back of the gearbox hits the tunnel, took the box out today and gently massaged the tunnel with a ball pein hammer at this spot to give a bit of clearance, everything back in and have been able to get the gearbox higher up in the tunnel,reduced the amount I have to pack the centre bearing down by 1/2, now only 14mm
Not sure if the O/D gearbox has this clearance problem, but can't see how you couldn't get away with not doing this for the C/R box.
 
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5spd cr box

I appreciate the post and discussion as I have a 5spd CR box in the barn that will someday replace the 5spd OD in my coupe. Thanks for starting the thread, and looking forward to hearing about the resolution
 
Hi bfeng,

Standing at the rear of the gearbox looking down onto the top of it, there is a protrusion sticking out on the RH side at the rear of the gearbox, looking at the end of this protrusion (ie, from the RH side of the gearbox) it has a metal disk in it held in with a circlip, this part of the gearbox casing is the problem, and the bit you need to reshape the tunnel for to allow the gearbox to move up higher into the tunnel.
Even with us doing this mod to the tunnel, the centre bearing on the drive shaft is still lower than the mounts on the floor pan of the car, I have had to make up some packer blocks to go between the mounting tags on the chassis and the mounting tags on the hanger bearing.

The problem is, the CR 5 speed is quite a bit longer than the 4 speed, and as the tunnel tapers down in size the further back in the car you go clearance becomes a problem to be able to get the gearbox high enough.
 
Right hand side of an OD box, no protrusion.
 

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That round thing at the top of the rear section of the box is what I'm talking about, on the CR box that bit sticks out quite a bit and is what causes the problem
 
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