Bonnet Scoop 2

The task for today was to finally cut the hole for the bonnet scoop.

Having already established that the oval filter wouldn't fit without some modification, I had trimmed down the air filter mounting ring by about 10-15mm which was more than sufficient to allow the scoop to fit.

After putting the scoop in place, I taped it firmly in place and using a china-graph pencil I marked the outline of the scoop on to the bonnet. I then marked another line inside this to allow for the flange of the scoop before taking the Dremel to the bonnet. At this point my trusty co-builder, Ali, asked me how much a replacement bonnet would cost!!!! Oh he of little faith.

Scoop taped in place and outline marked

And there it is... a whopping great hole

So with the hole cut in the bonnet it was the moment of truth - would the filter fit and not foul the scoop.

Fits like a glove

Next up the scoop needed taping back in place and the holes drilling for the button heads to pass through. Research had shown me that 27 screws is an ideal number which meant 13 either side of the centre screw. To ensure that they are equally spaced, I did all my calculations to determine the distance between centres and then made a little template (see pic below) which I found helped no end.

Template made to ensure holes are correctly spaced

Template ensures holes are correctly spaced

The holes were all drilled using a 3.2mm drill (I am using M4 button heads to fix the scoop in place) and then an M4 tap was run through the scoop and the bonnet, which had now separated into two separate skins. After tapping the first few holes it didn't appear to be adding any value so I ditched this idea and re-drilled them all with a 4mm drill.

Andy had advised that polyurethane (something like no more nails) is a good product to bond the two skins back together. So 'Unibond No More Nails' was applied and I used clothes pegs to hold the two skins in place as I didn't want them pulling too close together.

Now for some reason I just couldn't get the two skins to bond. I suspect the temperature in the workshop was too low as its unheated. Also when I had been running the drill through the bonnet it had caused the gel coat to breakout in a number of places which looked really messy. Needing to fix this and wanting to do something with the underside of the scoop which comes out of the factory with just the rough fibreglass finish with no gel coat,  I decided to call upon the help of Stuart at Carsmetic (he's the guy that filled and sprayed the bulkhead for me).

He agreed to fill the gap between the bonnet skins, repair where the gelcoat had broken out, skim the underside of the scoop with filler and then spray both the underside of the bonnet and scoop. Hopefully when this comes back it will look as impressive as the bulkhead.