Identify function/part

[S2_avant 19930325]

What is the function on this part ? It looks ok to take it away ?²

[Tractor Dave]

Front engine mount. Should sit in a carrier mounted to your front under aux rad. It stops the engine moving about too much. Also used to support crank locking tool.

[S2_avant 19930325]

Ok so its safe to remove. Have a intercooler in front and do i need it for crank looking tool i can put it back.

Thanks Dave for fast answer

[Tractor Dave]

I wouldn't recommend removing

[HPmuirt]

If that is a pic of the snub mount (can't enlarge the pic on this screen) and you mean "is it safe to remove whilst working on the car?" then yes, but as Mr Tractor says, don't leave it off

Cheers n
Si

[S2_avant 19930325]

Hmm ... why not leave it of ?

[S2_avant 19930325]

Aha .. ok ,, its not mounted to anything .. i have motor mounts under the engine .. 034 motorsport aluminium so the engine is really stiff anyway

[S2_avant 19930325]

Is there something that holds the holds the turbo and downpipe,exhaust weiht in the on the engine head , somekind of support .. and if it some aftermarket how do people often do it ?

[Antsa]

Turbo+downpipe weight is all on the exhaust manifold. Rest of the exhaust system is not. Fine if you use cast manifold like rs2 evo version. If going tubular, I would brace the turbo to keep the manifold from collapsing under high temperatures. However I've seen people using tubular manifolds without the brace.

[S2_avant 19930325]

I have seen without the brace to , but is there anybody who got some pictures how it could look in there Audi s2 ?

[Greg_S]

The engine mounts support the engine, the snub mount helps to reduce the movement of the engine pivoting on the engine mounts. I’d keep it in place. If you don’t it will likely affect your gear change and may also stress the exhaust and in particular the turbo mountings.

[S2_avant 19930325]

But if you have stiff engine mounts ,, aluminum .. how can it pivot on the engine mounts then ? How do people fit big intercoolers in front with snub mount ?

[S2_avant 19930325]

There is a lot of other cars exept audi with a lot of power that does not a support mount in front of the engine ,, i cant see that the audi engine needs it when built original. Belive they did like a extra support but if really needed ,, i doubt it

[steve briance]

Audi put it there for a reason. Leave it off and see whether the experience and caution of people on here comes true...

As mentioned - the mounts hold the weight of the engine but its longitudinally mounted, quite long and does rock around a lot. Your mounts won't resist all that torque and would quickly fail if not protected from the majority of the twisting forces as the engine twists them around.

[Lago Blue]

Don't snub the snub...

This is to echo all the sensible warnings above; and further, to detail some explanation of how it works:

Our two laterally spaced apart engine mounts quite properly largely support the motor from near its' center of mass (close to its' fore-aft C of G) and only really prevent it from tilting strictly left or right (whenever engine torque is applied to or released from the chassis, i.e.: throttle up, and throttle down), and are only able to do so; precisely because they are both some distance from the crank's center-line.

The motor / tranny assembly wants to twist around the crank-axis, only because about half of the engine torque is being resisted by the rear wheels.

However the motor / tranny assembly also wants to pitch, i.e.: nose-up and nose-down (again with any application or removal of torque to the chassis) with similar force. This pitching movement is best resisted by the similarly long distance that the snub is from the front-axles, which is the 2nd axis that the motor / tranny assembly wants to pivot around.

This is because the motor / tranny assembly (an otherwise writhing, flailing wild beast) also wants to react (or pitch) around the front-axles' center-lines, since the other half of the engine's torque is being resisted similarly; but here by the front wheels.

Our motor mounts (on which the motor is kind of balanced, front to rear as can almost be seen in the illustration below) cannot resist the fore-aft pitching motion at all well, precisely because they are necessarily too close to the fore-aft C of G of the motor / tranny assembly. In fact, the two motor mounts act as a kind of fulcrum across which the motor / tranny assembly rocks front to rear, only restrained by the two tranny mounts; and the snub. So hopefully one can visualize that (when viewed from above) the motor-mounts really work perpendicularly to the tranny and snub-mounts.

The two tranny mounts do help both the snub and the engine-mounts, but similarly they cannot replace either of those other three mounts. The five mounts together are just strong enough, less than five is not.

Many folks quite properly go to lengths to improve the effectiveness of the snub-mount (with more massive rubber ends, double-sided (top and bottom) receiver plates,) and not without first recognizing the critical need for this mount because each of the five mounts' individual effectiveness both allows the other four to best perform their specific tasks, and together they all last longer (there are other driving benefits you will also learn too). In fact the stock snub receiver bracket is made adjustable precisely so that it can be made to engage; just when and where the tranny mounts do, and for the discerning, a critical co-ordinated response deftly "mounted" to applied and removed engine power, that a worn snub rubber and tranny mounts then exposes as needing attention.

In order to best get all your torque (whether stock or extra-large inter-cooler enhanced) to all the tires' contact patches ASAP, one needs to correctly harness the entire power-train as Audi intended or you'll be waiting till the engine / tranny assembly stops moving before that happens (a very annoying phenomenon!). The snub is a small and different but necessary part of that; and has just a slightly different job description from what a motor mount (or a tranny mount!) must have. Its job is more fully realized dynamically than it is apparent statically.

Audi S1 flexible drivetrain connections.png