After 17 years of MGF ownership I decided to upgrade and changed my 20 year old convertible for a five year old 2L Roadster. I expected and got a more sophisticated vehicle with a hardtop, Bluetooth phone, larger boot etc. but was surprised at the rough edges still remaining in a fourth version of the car.
The first and most glaring issue was the awkward driving position, forced by the need to floor the clutch. Information from this board and a few minutes spent squirming under the steering column to adjust the link between the pedal and the clutch cylinder cured this one. The other transmission related problem was the stiffness getting into first and second gear with a cold gearbox added to a fairly snickety change in all gears. More squirming and I had changed the transmission oil for Castrol Syntrax Multivehicle 75W-90. The change showed instant improvement and I am surprised to find that the gearchange is getting smoother with time and mileage.
Next annoyance was cabin noise. On certain road surfaces the noise in the cabin verged on the painful. I know that some of this is due to five year old, part worn tyres but a major contributor is the boot floor that rings like a bell when tapped with a knuckle after removing the carpet. I bought ÂŁ40 worth of sound deadening pads and stuck them round the boot floor area in the more resonant places. The cabin noise is now more sports car like with a dull roar and I even have some pads left for under the seats when I get chance to fit them.
Finally wind, or more accurately wind coming round behind the headrests when driving with the top down. My MGF had a mesh windstop that was very effective but quite ugly. I bought a Lexan Mazda OEM windstop and fitted it between the rollover bars. Fitting took around an hour and the difference it made was well worth the effort.
Now to handling. I live quite near Wheels in Motion and made an appointment for lowering and resetting the geometry. They confirmed my suspicion that lowering springs had already been fitted, but not by them, and simply reset all the adjustments to optimum.
So now I have a quieter, easier to drive, better handling car, in other words a civilised roadster.
Totally agree! You’ve gone about this in a methodical way, identifying “issues” and rectifying them as you’ve gone along. This may be useful to existing and potential owners who have similar “problems”. relatively easily fixed, giving you the car you want.Â
Thats what i was thinking, i can’t see how an ND is five years old, that said in my limited time in mine i’d say the symptoms are still true of an ND.
This is a pack of 30 and I used about half of them, so you might get a smaller pack.
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The trick is 75%/25% in other words, 75% of the noise comes through 25% of the panel area, so you need to find the flexible panels that “ring” when you tap them with a knuckle. After treatment you get a dull thud. It’s not necessary to get 100% coverage by cutting the panels to fit as they do not insulate the noise, they reduce its frequency.
I’ve just contacted Silent Coat and advised them that I wanted to both noise and heat insulate my Mk3.5, their advice is below -
>> We recommend a 2 stage treatment. Applying one product and then another product over the top as a 2 stage process:
Stage 1) Treat the metal body panels with Silent Coat 2mm Mat to reduce panel resonance and body boom. Use on all metal panels up to 50% coverage for most cost effective results, or 100% for a fully comprehensive job. For your the areas you mention on your car we recommend 1 Bulk Pack. This product can be used on any metal panel in your vehicle, with the most common areas to treat being the floor, doors, wheel arches and bulkhead.
Stage 2) Use these products straight over the 2mm you have just applied. These tackle airborne noise that is not directly generated by the body panels and also insulate preventing heat transfer through panels:
Use Silent Coat Isolator in either 6mm or 10mm thickness. This is a special formulation closed cell foam with excellent thermal and acoustic properties ideal to reduce noise, insulate the vehicle and to isolate barriers and trim panels.
For these stage 2 products we’d recommend having a measure up to determine the correct amount needed. We suggest applying stage 2 products like a blanket, covering 100% of the panel. <<
This is correct. The ideal weight of pad in the perfect place can eliminate the resonance noise almost entirely, but there is a lot of good science involved, and depending on the panel shape maybe more than one pad location might be needed.
The tapping trick can be very useful; place a fingertip on the panel and move it around while tapping with another fingertip and listen for the quietest sound. That quietest spot is the place to apply a piece of deadener to damp out the resonance. It is a bit like placing a finger on a guitar string, in some place there is a harmonic in others it quickly kills the sound.
In my ancient Ford Corsair I initially thought they were being mean by placing such a small piece (approx 6" by 10") apparently randomly on the inside of the door’s outer skin, but it actually drummed louder when I stuck a much bigger piece over almost all of the panel. A loudspeaker designer then explained to me mathematically how to stop panels from resonating while cutting costs and weights of the cabinets to a minimum.
This was all forty-odd years ago, and I’ve not thought much about it since, but in essence find a spot that is not a harmonic distance across the panel in any one direction, ie the ratio of lengths does not divide nicely like 1:1 or 1:2 or 1:3 etc but might be more like 11:17 or 13:23 etc.
The weight of the damping pad matters as well, and a very rough guess at this can be found by noticing how hard one presses with the searching finger while tapping with the other.
This thread popped up in the “active” list and so I took a peek.
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I am now ÂŁ40 lighter as I have purchased from the supplied ebay linkÂ
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Thanks to all the posters for the info - very useful. I have also acquired some aquarium filter sponge for the drain tubes and will have a pop at installing it all.
When we go away for a few days Wendy packs as much as she possibly can in the boot. Sound absorbing clothes, all kinds of things, you know what girls are like! I stuff every available remaining space with important man stuff.
There doesn’t seem to be any significant reduction in noise in the cabin from boot or wheel arches. This makes me wonder if sound insulation kits are worth the effort and expense?
I have found the above to be true in my Mk4 and have wondered the same thing. One thing that does seem to make a difference is if you shove a big coat or similar in the area where the roof folds into - I suspect that would be a good place to investigate adding sound deadening stuff (not done it myself yet).
Good morning LilWashu,
Forgot to mention that there are coats and all sorts in the space where roof folds in to and that didn’t seem to make much difference either, just means can’t drop roof! It is a sports car anyway so if you want to travel in silence not the best choice.
I enjoy every moment in my ND, roof down whenever I can-------except today, pouring with rain in Whitstable.
In my own car the valves in the rear drain tubes had failed and there was a terrible noise in the car that sounded liked worn wheel bearings. I had a MGF a few years ago. Nice car but takes a bit of time to get to the engine engine cover off.