Engine Mounts

[2052006 10]

Out of the gearbox, top and lower engine mounts, which stop engine movement the most? Or are they all as important as each other?

 

I've come to the conlusion that I'm getting too much engine movement with my gti6 engine, despite using brand new Pug mounts all round and the lower one being a xantia turbo mount (a bit harder). I've got a good 3/4mm clearance on the m/cyl, but it still rubs a bit. Same with the gear rods. And god knows where else.

 

Just wondering whether I should invest in some group N gearbox and upper mounts / group N lower / or all three?

[j_turnell 137 3 Cars]

IMO I'd fit a group n bottom mount and group n rubber buffers for the top mount, make sure they are touching both sides of the mount and shim if needed, see how that goes, if that doesnt cure it then i'd get a group n topmount aswell.

[hengti 2]

i guess perceptions vary, but i felt that the order of effectiveness of the 'GpN' mounts on mine went: top engine mount - torque bush - gearbox mount

 

shimming GpN buffers up to the top mount created much more vibration than any of the others (again, in my experience)

[EdCherry 34 1 Cars]

i guess perceptions vary, but i felt that the order of effectiveness of the 'GpN' mounts on mine went: top engine mount - torque bush - gearbox mount

 

shimming GpN buffers up to the top mount created much more vibration than any of the others (again, in my experience)

 

 

Of course it will create much more vibration in the car thats logic, it will also stop the engine moving as much!

[trialster 0]

engine rock is controlled mainly by the bottom mount. forward and backwards, side to side shifting of the engine is controlled by them all. pretty much

 

i find that fresh standard O/S mount with standard 'packed' buffers and group N lower and gearbox do the tick nicely without shaking the car to bits!

[hengti 2]

Of course it will create much more vibration in the car thats logic, it will also stop the engine moving as much!

 

sure, but if the engine mount is stiff enough to begin with, there's not really any need for very stiff buffers (or any buffers at all - i don't think the Vibratechnics mount uses buffers for example - ?)

[Anthony 1,003]

The lower mount is the most critical to controlling engine movement in my experience, and I usually just run a Group N lower mount and standard upper, gearbox, and buffer mounts. Minimal extra vibrations, but well controlled engine movement without the on-off throttle driveline shunt that standard lower mount suffer from.

 

If you want to try a Group N lower mount Pete, I've got one in the garage that's pressed into a casting ready to fit that you're welcome to try

[2052006 10]

Thanks for the suggestions. The only thing I haven't changed is the top mount buffers and I have to say, the top mount moves in between these a lot. I'll have to look at that. I have ground off a bit off the exhaust flange and gained a bit of clearance and ground off as much as I dare from the m/cyl (about 1-2 mm or so) on the cambelt side, but hard driving still has the whole engine moving too much. I don't suppose it does much good for the engine/exhaust/driveshafts moving like this either.

 

Anthony - that sounds like a plan I'll be in touch.

[2052006 10]

Right, I have fitted a group N lower mount now and shimmed up the standard buffers in the top mount.

 

This certainly helps, but vibrations at idle are also felt a lot more. Not unbearable, but really wouldn't want it to vibrate any more! However, the cambelt cover is still rubbing ever so slightly. I know this because very scientifically I paint a bit of tip-ex on the cambelt cover and it leaves little white witness marks where it touches the m/cyl.

 

So far I have:

 

-moved the gearbox mount as far to the right as possible

-filed a bit of the side of the m/cyl

-filed a bit off the cambelt cover (still intact)

-angled the servo up by using: washers between servo and pedal box and washers between pedal box and bulkhead. I'm not sure if I should angle it any further as already I can't fit a nut on the bottom thread of the pedal box where it comes through the bulkhead, due to the washers on the other side. I'm guessing any more would be a bad idea?

 

 

Any further suggestions before I go for a Group N gearbox and top mount?

[j_turnell 137 3 Cars]

Just get some group n buffers, there only a few quid, the vibrations do die down, takes a good few miles for them to bed in.