Mx5, Chapter 2

bruce · Postby **bruce** » Sat Oct 31, 2015 3:12 pm

I've got the same pod setup. I fitted a black flower pot over the filter to keep the crud off (pot edge faces forward).

The American · Postby **The American** » Tue Nov 10, 2015 11:39 pm

The Noosa Beach Classic Car Club and Historic Racing Car Club's Noosa "The Hill" hillclimb took place on 7th and 8th of November.

Noosa "the hill" 2015 by Hanson Wheeler, on Flickr

I entered along with five other drivers in four other Mx5s.
John McKenzie with his NC:

Noosa "the hill" 2015 by Hanson Wheeler, on Flickr

Luke and Peter Barnes with their Blue, caged and variously modded NA:

Noosa "the hill" 2015 by Hanson Wheeler, on Flickr

Along with Lewis Pitt and Magpie (both of who's cars I neglected to snap)

Day one was hot and humid, and after the sighting run, my first timed run was a new PB of 67.24, followed by a 67.87 and a 67.34. At the close of day one, I had had met my objective of a new PB. This was a good thing given that rain was forecast for the following day, along with cooler temps (around 24c instead of 30c+). The only incidents I heard about was a black Gemini coupe that found a wall at some point, and a Porsche that dropped quite a bit of oil from turn 7. Both cars returned to continue racing the following day, with some scuffs beaten out of the Gemini a little.

After my last run of the day, I watched the last 60 or so cars pass through turns 3, 4 and 5. I was quite surprised by how many of the drivers appeared to allow their cars to 'push' through the corners rather than have neutral or over steer attitudes. They also seemed to be using much more of the track than I was - if there was no cone to hit on the corner, they were putting a wheel on the inside edge dirt/grass.

Day two was true to forecast, and the day began with a very damp track, and my first run was a cautious 81.83. The oil dropped by the Porsche continued to be a hazard. Recognising that my following runs would not be very quick, my second run was spent finding the limits of grip on the damp track and pushing the car until it got out of shape. If anything this helped with my confidence as the day progressed and the track dried.

In one of the gaps between runs, I was chatting with Magpie who mentioned that he's was holding third most all of the way through the course. I had been changing to second several times. In my last and fastest run, I held more speed, accepted a little more understeer and held third except for one corner. Another experienced competitor pointed out that the run through from the start line to corners 2 and 3 is actually one opportunity for speed and time reduction because it is relatively straight - in my faster runs, I tried shifting earlier into second in order to minimise wheelspin off the start line.

Here's how it came together:

The American · Postby **The American** » Tue Nov 10, 2015 11:49 pm

Given that I'm in Noosa, and had been thinking about getting my exhaust upgraded to 3" (replacing the current 2.5"), I decided to pay a visit to Turbo Yoda and Dose Vader of MCM fame at AM Auto in Tewantin. Turbo Yoda was not around, but Miles (DV) took some time to look at my car, and discuss what value might be found in doing the upgrade.

For a 1.8l with a 2560, he thought 2.5" would be more than adequate - Unless I was simply looking for the bling factor!

So for now, Unless I can come up with a more compelling argument for myself, I will be sticking with what I have.

Postby **Okibi** » Wed Nov 11, 2015 12:17 am

For many years the Corky mantra amongst turbo miata owners was that a 2.5 exhaust was fine unless you were making huge power, FM's dyno testing proved that a free flowing straight through muffler was important. What is your muffler like?

Pressure difference each side of the turbo and keeping the heat in the dump pipe and not your engine bay will also help, a nice fat stainless dump will help (if you don't already have one).

A high flow cat will also help, if you need all 3 chat to Dann.

There's plenty people who mention power gains going from 2 1/2 to 3" but that might also be because they upgraded the dump, cat or muffler as well.

Magpie · Postby **Magpie** » Wed Nov 11, 2015 8:13 am

Whilst I did use 3rd almost exclusively up the mountain, it was difficult to keep the car above the magical 5,250 RPM. The car did pull well in 3rd below 5,250 but I think it would have been faster to drop back to second on a few more corners or carry more speed through the slower corners. Alternatively gokart style left foot brake right foot accelerator

I found an early change into second helped off the line. However did you see the NASCAR starts, it was using 2nd gear and the noise!

The American · Postby **The American** » Thu Nov 12, 2015 8:06 pm

I thought that NASCAR was just going to break. It seemed a bit like running a motor cross bike in a GP...I wonder why they have it. It's not like they'd have picked it up locally at the end of a season?

Here's another version of the wet run, with some slow motion thrown in for fun...

The American · Postby **The American** » Fri Nov 13, 2015 9:17 pm

I arrived home from Noosa to find that the Bear's delivery service had been...

Bear Hooks

Bear hooks

Bear hooks

Very nicely made bits of gear. I think I'd like another set engraved with "never need me".

The American · Postby **The American** » Thu Dec 03, 2015 7:09 am

Okibi wrote:For many years the Corky mantra amongst turbo miata owners was that a 2.5 exhaust was fine unless you were making huge power, FM's dyno testing proved that a free flowing straight through muffler was important. What is your muffler like?

Pressure difference each side of the turbo and keeping the heat in the dump pipe and not your engine bay will also help, a nice fat stainless dump will help (if you don't already have one).

A high flow cat will also help, if you need all 3 chat to Dann.

There's plenty people who mention power gains going from 2 1/2 to 3" but that might also be because they upgraded the dump, cat or muffler as well.

I've got the AVO cast dump, and I have no idea how good the CAT or muffler are in terms of flow. I don't know how I'd even tell if what I have is any good!

Unfortunately Dann's Stainless Kitchen is 1000km away.

Postby **Okibi** » Thu Dec 03, 2015 9:20 am

Never liked that "cut away" design of the AVO dump. Sounds like it would take a day to drive to Dann's and half a day to drive back.

The American · Postby **The American** » Thu Dec 03, 2015 10:47 am

maybe I should just get a Trackspeed EFR manifold and a 6758 - surely that would be sufficient excuse to get a decent exhaust made. **wakes from day dream**

TrackAttack · Postby **TrackAttack** » Thu Dec 03, 2015 6:29 pm

Exhaust size for flow is relative to temperature... I'm pretty sure Charlie had a 3" dump, but it necked down to 2.5" pretty quickly. A CA18 I built recently made 200rwkw at 15psi with a 3" divorced dump, that reduced to 2.5" at the merge, maybe 30cm away from the turbo (the cat was super close, and was a 2.5" bullet cat cut back to suit the 3" pipe), and continued as a 2.5" exhaust the whole way down. Will it make more power with a 3", probably not. Is it worth the hassle trying to fit a 3" exhaust, no way. I think if you want improvement, a good custom divorced dump pipe is the way to go. After the cat, if it was my car, I'd stick with 2.5" as it clears the bracing/diff much better and won't make much of a difference.

The American · Postby **The American** » Thu Dec 03, 2015 9:22 pm

My little turbo does not require a bigger exhaust. "It will not make the boat go (much) faster"

The American · Postby **The American** » Mon Jan 04, 2016 7:04 am

Bolting green things to white things.

[url=https://flic.kr/p/CC6fvm]

[/url][url=https://flic.kr/p/CKkwLS]

#frogarms #bossfrog

Magpie · Postby **Magpie** » Mon Jan 04, 2016 7:24 am

Nice, I have added some green to my car as well. However it is visible all the time, I had some paint left over when painting the mudguard on the bike (Kawasaki candy lime green).