Mopar Muscle Association UK

as many of you know im going the motor plate route with the dart, also using a mid plate. thats simple but what do i do with the tail end of the gearbox? can i use a rubber mount?
any advice greatly apreciated.
cheers

A Poly mount is best.
I would definitely NOT solid mount it

Pete wrote:A Poly mount is best.
I would definitely NOT solid mount it

Rubber mount trev or you'll be using the G/Box tailshaft as the flexi joint

Trev I looked into this when mounting the engine in the Bee and spoke to several top guys, the idea of the mid mount was to use the block to strengthen the tubes of a light weight rail type chassis giving weight saving.
Looking at your build the chassis looks plenty strong enough so unless you are not looking for extra strength or stiffness then a front plate set up with rubber rear gearbox mount should be fine.
If you need a mid plate I have one.

cheers guys, it probably isnt necessary at the moment but im planning for the future ive nearly completed the mid plate now, just need to work out a polly bush mounting for the box and its sorted cheers chaps

With a front plate only there must be a lot of strain on the gearbox mount, would a poly be better just to last longer?
Anyone use poly bushes in the front plate- i'm sure i've seen this done somewhere?
How do you decide where the motor will sit? I assume you want it as low & rearward as poss?

db wrote:...How do you decide where the motor will sit? I assume you want it as low & rearward as poss?

There are specific measurements for off-setting an engine in, say an "A" body (Schumacher creative industries can supply this); but I think Trev's car has the motor centrally mounted - that is the case in my Roadrunner - it obviously has an impact on the rear end set up.

with any offset on the tail shaft the angle at both ends much match

as the joints turn the tail shaft speeds up and slows down past as each cap on the joint passes a specific point

if the angles vary you put verything under stress as one end is slightly speeding up or slowing down at a dffernet point from the other

in theory as long as you do not take the joint out of spec as long as both angles match should be ok

and that is in all plains.


i.e if motor and box slopes down to the back by 15 dgrees
1 there is probably something wrong but

you do not want the pinion pointing up directly at the box
that would be a streight joint at the pinion and a 15 degree bend at the box. pinion joint would tarvle at uniform speed all the time
box joint would fast slow fast slow 4 times in each revolution

same for side to side.


you can simulate this effect if you have a tail shaft and yolk lying about

bend it to something daft like 45 dgrees and try turning it

it aint smooth

even more obvious with the tiny Uni joints you get in technical lego....i once lost all steering, spread the joint, it was a nightmare smashed me hand right into the hearth and had to rebuld the whole front end. my steering column was at 90 degrees to my rack....no no no said the instructions no more than 60

dave

In full chassis cars, the engine is mounted centrally and the crank height is usually set at diff height so that the whole drive train is inline. When it comes to mounting the gearbox, torsional chassis twist is what you have to take into account. the engine block is stout enough to be solidly mounted front and rear and to stop the chassis twisting. The gearbox tailshaft is not very strong, a flexible gearbox mount is there to allow the chassis to flex, not to stop the gearbox moving.

cheers guys, mid plate is now done, tomorow i will start looking at a polly mount tail shaft mount, hope ive got a big enough billet in stock