Engine Bay Cooling

Some kit cars have bonnet scoops, some have louvers, some even have NACA ducts, but the Avon has no openings as standard.  For most of the year this is not a problem, but I had noticed that during the summer months, there can be quite a big heat build up and the top of the bonnet is very warm to the touch.

So I weighed up a few options, including fitting ready made grilles, but in the end I decided upon some simple holes.  I used hole saws in the cordless drill with the torque turned right down.  Then, once the  holes were done, I glued black mesh to the inside of the bonnet with Grip-Fill.  I'd previously had success using this on the inside of the GRP bodywork to affix things, such as cable tie mounts.

Here are the four holes that allow escape of some of the heat from the exhaust headers:

And here are the two larger holes centered on the midpoint between the two K&N filters.  As well as allowing cooler fresh air in to the engine, they also allow out of the engine bay that little extra induction noise!

Overall, a simple modification.  The engine bay definitely runs a little cooler and in my opinion its added some additional aesthetic interest.

Bonnet and Nose Cone Finished

Finally after much drilling, filing and swearing I've finished fitting the bonnet and nose cone.

The nose cone needed some cut-outs making for the lower front wishbone as well as the steering arm.  Bolts were added on each side and one underneath to mount it to the chassis.  I used epoxy to add a washer to the outside of the body around each hole.  This tidied up some rough edges (where the fibreglass started to split due to it being thinner in certain parts) and also spreads the clamping forces more evenly.  The lower bracket had to be extended to reach the lower part of the nose cone.  I think this is due to the fact that the nose cone sits slightly forward of its normal position to accommodate the Tiger alloy radiator, which is already inclined to the maximum.

With the nose cone in place this provided a reference for the bonnet.  This had to be cut quite a bit, very carefully, at the scuttle end.  In its natural position there was the usual huge gap on the drivers side, between the bonnet and the body side panel - maybe 25mm or more at the scuttle end.  I evened this up and now I have a small, but even, tapered gap each side.  The only down side is that the bonnet is trying to rotate back to its natural rest position.  This causes the front of the bonnet to rise up where the inlet bulge is.  This wouldn't be so bad on the version of the bonnet without the bulge because the spring clamps would pull it back down.  However, this is not the case with the asymmetric bonnet that I need to house the throttle bodies and air filters.  Hopefully it will settle after being clamped in position for an extended time.  If not, I might have to look at other solutions.  Possibly a couple of dowels and locating holes between the bonnet front and nose cone rear.  Anyway, I am glad this chore is over.

Tiger has made a good job of reworking the main body tub.  It is a big improvement over the previous version.  It is just a shame the bonnet and nose cone are not yet up to the same standard.

Self tapping screws were sprayed with satin black Rustoleum paint and used to fix the grille to the nose cone.