so...... an update of sorts
my first track day experience went well. a half day at Oulton Park on the 24th feb, I'd had an oil change and fitted EBC Yellow stuff pads (which had an immediate effect, slightly spongy with the first couple of cold presses but after that they're unbelievable conisdering i just have standard discs). I survived without going off and by the end was feeling pretty confident. Only a blown exhaust that i've since replaced with the mx5parts stainless steel one.
Heres a couple of pictures, there was another 5 there.. a track ready mx no.'78' any ideas who's this is?

and so to my next budget 'mod'
I'd started to get concerned about the heat under the bonnet when i'm pushing it on the track. I've got a fairly universal looking mushroom air filter at the back of hte engine bay with no heat protection from the mainfold thats next to it. before doing anything drastic i thought i'd test my theory so i used an old digital thermometer from my dads film processing kit. Reading from inside the filter itself, it ran under the bonnet and through the passenger door sil into the car so i could check it on the move.

ambient air temp: 2 degC
town driving (engine cold): 12 degC
motorway driving (engine warm): 34 degC
town driving (engine warm): 25 degC
engine at rest for 5 mins (engine warm): upto 50degC
after seeing these results I was confident I could reduce these temperatures by 1) getting a better flow of air and 2) deflecting the heat away from the air filter
i'd seen a couple of options for more air induction either replacing the indicator with a vent or a vented headlamp cover but the cheapest was £60 + postage + painting etc. I had a plan.. to buy an old headlamp cover, cut a hole in it and use some pipe to channel air through to the filter.
For the parts I managed to pick up a set of headlamp covers in black for £20, I'd also bought some cheap aluminium ducting from halfords and a plastic sink drain cover to stop any gunk getting in.
in the absence of a proper hole-drilling 50mm drill bit i used an 8mm metal dril bit to perforate a circle i could snip out with some wire cutters.

i'd sprayed the sink cover black to match the lid and used a unibond 'Extreme power glue' to hold it down. With a 60mm diameter pipe from the back of the light unit i took it out on a similar test run. the temperature was down at speed but only by a few degrees. there was an improved feeling of acceleration at motorway speeds.


The problem was still the amount of airflow going into the engine bay so i decided to add a 'scoop'... following the budget theme and a trip to B&Q i had a 67deg 68mm diameter piece of drainpipe. I also bought a smaller diameter ducting pipe (40mm) fro halfords as thes would fit into the back of the headlight unit and therfore better access to the air.

the temperatures are now as follows...
ambient air temperature: 8 degC
town driving (engine cold): 12 degC
motorway driving (engine warm): 21 degC
town driving (engine warm): 20-26 degC
engine at rest for 5 mins (engine warm): upto 50degC

Comparing the two sets of results i'm pleased with the outcome. given the higher ambient temp today the lack of change in the slow speed temperatures doesn't worry me as its at speed onthe track where i should see the benifit and 15 degree lower temperatures with a higher ambient temperature.
I know it very much looks like a bit of drainpipe stuck to to a bit of a sink stuck to the wrong colour headlamp lid but it seems to do the job and hopefully if i can knock up a heatshield i can lower those temperatures further.
Let me know what you think
Matt
1996. UK mazda mx5, silverstone metallic
2003. Mini cooper, British Racing Green / White
1993. Eunos Roadster Vspec, British Racing Green