floor pan vibrations

[lola]

At speeds above 69mph i get a loud vibration under my elise 135S , this appears to be coming from the join between the two floor pans, there are no fixing holes visible where bolts may have been, anybody have any idea how the pans are secured or do i have to stick to mountain roads where you do not get the chance to open her up????

[Bibs]

The undertray and diffuser are joined together, this pic should help where nut, bolt and washer (6,7 & 8) are replicated 5 times along the join... 

 

[lola]

thanks bibs

i did not realise there were three plates under the car, my vibration was coming from the join between the rear pan where it joins, in line with the roll bar, hence on a recent alpine jaunt, i came home with the nickname "gaffer" due to the repair i made

any thoughts and many thanks

 

lola

[Advantage]

Get the rear of the car up onto ramps and have a poke around. (Stick a few photos up on here if you're unsure as to what you're looking at) It might be that the tray is not located correctly into its forward mounting, which will mean dropping the tray and re-securing.

 

Make sure that the four allen bolts labeled "3" in the above diagram are all tight. Could it be that the exhaust is rubbing/resonating on the undertray? 

[lola]

many thanks will check it out later

thanks for the help

lola

[softlips]

Is the noise in a particular rev range or is it just speed related?

[lola]

softlips

the noise is purely speed related and is caused by floor pan vibrating located in line with roll bar, i sorted problem by gaffer taping it my query is how is the pan mean't to be secured as there are no bolt holes

thanks lola

[Bibs]

There should be a lip that it tucks above at the very front of the undertray...

[lola]

bibs you are a gem many thaqnks for your help

lola