Project MX-5 (Part 4 – breathe in and out)

First published in December 2015:

Project MX-5 has been resting since its debut racetrack outing . Oh, sorry, if you’re not familiar with the goings on regarding my project/track car then you can find other updates elsewhere on this site.

What’s really great about this project is that whenever I meet some who has been following the series closely, they want to know what’s next. I had a few plans in mind, one of which was to get the suspension sorted but that one will have to wait until next year.

Busy days

Matters get a bit frantic at the CAR offices around this time of year as we try to meet looming deadlines before a well-earned summer break. Subsequently my track toy has been sitting quietly in the CAR garages collecting dust. Work assignments and personal travel have kept me from performing some of the upgrades I was really hoping to have completed by now.

More noise = more power?

At the initial track day outing more than one person remarked that my car was very quiet out on track. I realised just how quiet it was when running in close proximity to other cars and I could not hear the Mazda engine… at all.

I knew that the car needed a bigger exhaust to breathe better, and sound sportier as well. I made a few calls and the affable Dick Bate, owner of Powerflow Salt River, agreed to hack out the original system and replace it with something more suitable.

Quick and professional

Mr Bate has worked on similar cars before so he knew exactly what to do. I dropped off my car at their workshop around 10 am and received a call around four hours later to confirm that all was sorted. I could hardly believe it, I was expecting the full job it to take at least a day.

When I pitched up at the shop the car still was on the hoist and I had a good look around to see what was done. The standard set up was cut at the end of the exhaust manifold and replaced with a 57 mm straight-through pipe. There is just one silencer at the very end and a fancy new exhaust tip rounds it off. I couldn’t wait to start it up to hear the difference

Fruity

When started I could hardly believe the change. At idle the motor does a good impression of a rotary (perhaps remembering its Mazda roots) and when revved up it sounds far more fruity than before, as though there is a lot more firepower under the hood than there actually is – another aspect that needs to be rectified.

On the drive back to Pinelands I was caught in traffic so there was no real chance to rev out the engine for the full vocal range to be heard. But I did give it the odd smile-inducing blip in traffic just for the heck of it. Back at the office colleagues who heard the car mostly shared the same grin that I did.

If you click on this link you can watch clips of the car before and after the exhaust was replaced.

And more air in, too

With the exhaust sorted it was time to let more air into the motor. Thankfully my friends at ATS Motorsport had just the thing: a replacement K&N panel air filter. The benefit of this filter, as opposed to a larger cone item, is that it drops straight in, no modifications needed.

I just opened up the airbox, removed the stock paper item and installed the wire and gauze replacement. Interestingly, after all these years the American filters are still hand-made.

Feels quicker

Brief experimentation in and around our offices shows that the motor responds to throttle inputs with added vigour, whether those difference reside in my head or are real I plan to test at an upcoming track day by comparing newer speed traces with the older data logs.

As usual all comments and suggestions are welcome.