Pros And Cons Of Solid Mounting An Engine (Specifically A V6)

[Goliath 94]

I would like to solid mount my V6 engine in my 205, the reason being I have no room for engine movement. I currently have BBM solid rubber mounts but there is still more movement than I would like as I have the front exhaust rubbing on the radiator under hard acceleration and I have (I assume) the diff touching the subframe on hard RH turns.

 

Are there any cons to solid mounting an engine, if so are any of them less of a concern, compared to a 4 pot, due to this V6 engine being regarded as a very 'smooth' engine. (I have no idea if it is this engine in particular, or all V6's which are regarded as smooth, I have just heard several people mention it).

 

I plan on doing away with the battery tray and making a one piece gearbox mount that will bolt straight from the 3 bolts on the gearbox casing up to the 4 bolts that the battery tray uses in the chassis leg, similar arrangement with the top mount. Not 100% sure on the lower mount yet, although I plan to use more than just the single fixing point on the subframe.

 

I understand one con is vibration, I don't mind this, unless it is so bad it is likely to break windows etc!

[Sandy 191]

I'd only do it on a race engine installation and then it needs to be done with great care, designing the mounts to allow some give for expansion without cracking. It needs regular bolt checking and the vibration wouldn't be bearable on a road car; the buzz on the roof panel on the overrun for example is much like a prop engine plane landing on you!

[welshpug 1,666]

s*it breaks

 

205 is nowhere near stiff enough, especially with 200 lbft yanking it about

[Goliath 94]

Damn, that's that idea out of the window then, any other ideas on how to limit engine movement? I have no space to move the engine in any direction so can't simply move it away from the obstacles.

 

Are there any rubber mounts stiffer than bbm ones?

[welshpug 1,666]

get a 405

 

grind away whatever is rubbing.

 

I think vibratechnics mounts have less rubber, but dont know about movement.

[Goliath 94]

Ha,

 

Can't really grind away the exhaust, radiator or the diff. Can possibly grind away some of the subframe but it isn't ideal and would only solve half the problem!

[Dizzee stuff 33 1 Cars]

Fit another steady bar near the top of the engine if you have space.

[jackherer 543]

V6 engines are not inherently balanced like straight 6 engines, they have some end to end vibration. http://www.autozine.org/technical_school/engine/smooth3.htm

[Miles 331 1 Cars]

The VT mounts are better, the only ones I use these days. But as the tops mounts still only hang the engine you still get movement, the 309 I did was fine on them but as we know room at the front is better, The idea of another lower mount is good as again they are the only ones that stop engine movement and being off centre doesn't help either