Lancia Motor Club

Model Technical and Interest => Fulvia => Topic started by: Caracad on 21 March, 2016, 10:38:01 AM



Title: Subframe Rubber Mounts.
Post by: Caracad on 21 March, 2016, 10:38:01 AM
Since having the Fulvia I have always had reservations about the way it drives.
The engine is fantastic. Now that it is all set up properly, its smooth and eager and pulls with verve and character. Love it.

The overall feel of the car however, seemed a bit disconnected.

So this weekend, I removed the outer part of the rear subframe mounts to investigate. Nothing wrong with the mounts, as far as I could tell. The rubber was in perfect condition.
However I did notice that as designed, the rubber mounts are not compressed when bolted up. So I decided to try something.
I cut approximately 10 mm from the end of the outer funnel shaped aluminium bobbins (for want of a better word). The bit I cut of I then put under the bolt head.
I was then able to wind up the bolts and compress the rubber mounts. I then did the same on the front mounts.

Result is fantastic. Everything about the car feels better. The whole car feels of a piece and solid. The steering is much more precise and has lots of feel.
This gives you much more confidence to chuck it around bends and it just feels great. Its also easier to drive smoothly, with less "backlash" in the drive line. In short it now feels as I thought a Fulvia should.

I was expecting a payback in NVH, but honestly I couldn't really tell. There may have been a little more road noise, but its the engine you hear. You probably feel the road a bit more, but in a good way. Ride if anything is better, as gone are the secondary reverberations I used to notice after a big bump, as the body and subframe moved in apposite directions. Anyway, the ride seems much more sensitive to tyre pressures than anything else.

I also reckon the front body structure will be less stressed as it's now supported better by the subframe.

I realize this is all a bit controversial, as my car is no longer as Lancia intended. It could be however that the mounting rubbers have deteriorated. They are over 40 years old after all.

Also I was wondering whether Rally cars used stiffer subframe mounts.

Anyway the main thing is I now love the car even more and it cost me nothing.


Title: Re: Subframe Rubber Mounts.
Post by: davidwheeler on 26 March, 2016, 10:15:58 AM
Interesting....    I've just had the subfame/engine out to renew the clutch and am wondering about retightening the bolts as the engine/gearbox rocks forward and back and it is difficult to drive smoothly.   How much of this is in the engine mount and how much in the subframe I am not sure but I may try some spacers in the subframe mountings.   Also, I noticed that the adjustable mounting on the RH side of the engine was sitting clear of the subframe so have eliminated the slack but wonder if it should be under some sort of comression?


Title: Re: Subframe Rubber Mounts.
Post by: lancialulu on 26 March, 2016, 03:28:58 PM
Interesting....    I've just had the subfame/engine out to renew the clutch and am wondering about retightening the bolts as the engine/gearbox rocks forward and back and it is difficult to drive smoothly.   How much of this is in the engine mount and how much in the subframe I am not sure but I may try some spacers in the subframe mountings.   Also, I noticed that the adjustable mounting on the RH side of the engine was sitting clear of the subframe so have eliminated the slack but wonder if it should be under some sort of comression?should be just touching. You have a rubber pad under the mounting??


Title: Re: Subframe Rubber Mounts.
Post by: Caracad on 27 March, 2016, 07:13:00 PM
David,
The right hand adjustable mount is a stabiliser and should have clearance to the subframe. This limits rotation about the crank  Centerline. The engine mounting arrangement in the fulvia is excellent.
Movement in the subframe will be about the axle. This is why longitudinal engines suffer less backlash than transverse engines where engine and drive torque act about the same axis.

Anyway, I think that perhaps the Fulvia subframe mounts where aimed at reducing NVH as much as possible.
In the Coupe, which is more of a sports car, perhaps a firmer set up suits the car better.