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Posted: Tue Nov 25, 08 11:20 pm
by Anonymous
much more happened blue???

Posted: Wed Nov 26, 08 8:25 am
by Blue
Yep, still getting a bit done every week, still don't have as much time to spend on it as I'd like at the moment. Managed to get another 35lb off the nose, which is nice. Will do an update soon when there's something worth looking at.

Posted: Thu Nov 27, 08 6:56 pm
by Blue
Today I have mostly been mocking up engine limiters. These are to stop the engine flexing rearwards on the motor plate on a hard launch. I've used left and right handed rose joints for max adjustability. And no, I won't be using copper pipe....

Posted: Fri Nov 28, 08 10:05 am
by Ivor
How on earth did you take that pic Blue? :roll:

Posted: Fri Nov 28, 08 10:30 am
by Dave-R
No headers in the way by the look of it. ;)

Small digital cameras are amazing for seeing where you cannot get your head and eyes into.
Look at these two I took in my transmission tunnel so I could check the clearence on the overdrive unit.

There was no way I could have checked this without the camera.

Posted: Fri Nov 28, 08 11:00 am
by db
What causes that then?
Left-right force is obvious but front-rear... Is it just the weight of the motor getting chucked about or is there some transference of torque?
Wouldn't you get more leverage for less weight if you braced further away from the motor plate? Do you have a trans plate- if not would that do the same?

I used to have to ratchet-strap my truk gearbox down but that was cos the rubbers had rotted away from years of bathing in hot fluids :oops: It used to jolt so hard it'd knock itself out of gear...

Posted: Fri Nov 28, 08 12:33 pm
by Blue
Think about it this way, you've got about 800lb of engine and gearbox held in position by a wide motor plate, under hard acceleration the whole lot will move to the rear because the motor plate will flex. Hard braking will cause the whole lot to shift forward. The limiters mounted directly to the block and chassis will stop that from happening. A solid gearbox mount would achieve the same thing but that has the nasty habit of breaking the tailshaft.

I had to do something similar years ago with my 4 speed Duster, I was trying to find out why I couldn't get a clean gear change under hard acceleration. I noticed the engine moving backwards and forwards on the motor plate when I was pressing the clutch pedal, effectively taking up the set clearance on the release arm. Once the engine was limited the problem went away.

Posted: Fri Nov 28, 08 12:37 pm
by GTXJim
I have the same braces on my motor it stops the motor from moving front to back, probably more important on a manual, but you will get movement on a hard launch even with an auto

Posted: Fri Nov 28, 08 12:49 pm
by Pete
I think they are well worth having.

Hausers' could not fit braces on the Sox in the Engine bay due to the humongous headers. Instead they fitted ones off the Gearbox Cross member that function in the same way - these are in compression during a launch. These mount to the original "ears" that the transmissions had when being managed down the production line.

I need to fit ones to Julie's car, but will have to check on Header clearance first for the most simple installation options.

Posted: Fri Nov 28, 08 12:50 pm
by Dave-R
I wonder if that same thing would cause bad crank thrust bearing wear on an automatic...? :?

Edit.
Naah. Just me not thinking it through. :roll:

Posted: Fri Nov 28, 08 12:50 pm
by latil
On something completely different,a Morris Minor uses an adjustable bowden cable from the back of the gearbox to the chassis to stop the fan hitting the rad.

Posted: Fri Nov 28, 08 1:02 pm
by Pete
Dave wrote:I wonder if that same thing would cause bad crank thrust bearing wear on an automatic...? :?

Edit.
Naah. Just me not thinking it through. :roll:
Nope, but you can imagine the amount of grief a 4 speed gives the thrusts every time you depress the clutch (and keep it held down for fairly long periods in traffic, etc). Another reason why I don't like 'em....

Posted: Fri Nov 28, 08 1:22 pm
by Ivor
I've stripped a perfectly good, smooth running 440 that came out of a manual with 60 thou end float on the crank...you wouldn't have known driving or listening to it!

Posted: Fri Nov 28, 08 1:40 pm
by Dave-R
Which is why I couldn't understand why I had 62 thou endplay on my automatic 440 when I checked it. (3.5 years ago now!)