"The Mazda" zoomzoom's NA Track toy

[zoomzoom]

Splitter has a few brackets behind the bumper that seem to do the trick. The wing setup is just done by feel, I got the car setup to be fairly neutral before playing with aero at all and then aimed to get it feeling fairly neutral again after putting the wing and splitter on. I am not under any false impressions about my $100 ebay wing, however if at some point I find the funds to get me a decent wing then I will probably consider giving a little more effort to the setup of the package.

If anyone is interested I have just put up the video of my quickest lap the other day at Lakeside on youtube, this was a 58.09s


Cheers,

Tim

[zoomzoom]

So I haven't done anything to the car recently aside from change the oil but I did take it out to the MX-5 club trackday at Lakeside and managed to improve on my PB a little.

I managed to get the time down to 57.44s but I was very happy with being able to manage 57s fairly consistently after getting the car and myself dialed in a little getting consecutive laps within a few tenths several times. I was especially happy with the session I managed my PB in, after getting things warmed up I managed 4 consecutive laps within a couple tenths, here are the times from that session.

4-11.JPG

Unfortunately my camera had gone flat before the quickest lap but I did get a lap from earlier in the day which was about a tenth slower at 57.56s. You can see in this lap I am still a little messy and slightly off line from where I would want to be in a couple places so there is definitely still room for improvement but I was quite pleased with the times I did manage. Here is the youtube of that lap, please excuse the terrible sound and poor image quality


Cheers,

Tim

[track_addict]

Wow. This car is awesome. I don't know why I didn't find this thread earlier! Top quality work. Will defiantly follow your progress mate.

[james_p93]

love hearing updates on the car! keep this up! watching u and this car blows me away

[zoomzoom]

Bit of an update, after the last track day I inspected the tyres to see if I could get one more day out of them, since there was only one left for the year I didn't really want to get a brand new set just now. Anyway, it ended up that the 4 tyres were at slightly varied levels of f**ked to completely f**ked! The worst one was on the front right, it ended up there after struggling for traction a little too much on the left rear but it was a little too late by the looks...


To get me through the last track day I was lucky enough to be lent some used Kumhos by one of our forumites MattR.

I picked up the tyres last Friday evening then thanks to Jason ant Automotive Plus I managed to get them fitted up that night ready for Time Attack at Lakeside Saturday morning!


Saturday came around and it was pissing down rain, great weather for a trackday especially at lakeside. I sat out the first couple of sessions in the feint hope that it eased off but by the third session of the morning it was still not looking any better. I decided to go out for a few sighting laps to get a feel for how bad it was since at this point it did not look like it was going to get any better. I can tell you now that it was incredibly slippery on fairly worn semis which have been sitting for who knows how long!

I had absolutely no traction so just tried to drive through the wheelspin, I figured it could only help to scrub the tyres a little. Still on my warmup lap coming onto the straight for the first time I heard a loud POP! which was obviously not a good thing. The car still drove OK but everytime I applied the throttle I felt it single spinning, not ideal when the car is fitted with a locked diff! After pulling into the pits and jacking it up I found that if I spun the left wheel I could see both driveshafts spinning, so the diff must be OK, but the right wheel was not spinning, thus the cause then became apparent.


Thankfully I had some more driveshafts and uprights at home about 25 minutes away, so a friend (toppertee on the forum) who had just arrived to see how things were going offered to go back to mine and pick them up. He arrived back and I managed to get the new shaft in and another upright fitted so I didn't have to crack the hub nut and got the car going again after lunch.

The weather began to ease after lunch firstly from rain to drizzle and then by the last couple of sessions the rain had cleared. The track slowly dried out since it was still overcast but by the last session of the day the track was mostly dry with several damp patches and only a couple of wet patches. The track temp was also quite cool so the tyres were pretty iffy but I was quite please to manage a 58.14 in the end, about 2.5 seconds quicker than the next quickest car .

As well as getting the quickest time of the day, I got awarded enough points win the 2WD Forced induction class for Time Attack 2013 .

Here is the video of my best lap for the day, still pretty tentative but went OK.


Cheers,

Tim

[Magpie]

Congrats on the win.

[MattR]

I showed you what you needed to bring the tyres back Tim, just should have put the call out a week earlier.....

[16bit]

for the money would you recommend the bc coil overs?

[MINX]

Congrats on the Win Tim - Well Done!

Stu

[Magpie]

Sorry about hijacking your thread!

As I said previously, the ones being used on zoomzoom's NA Track Toy are the ER version of the BC's, the same as I have. The ER have adjustment for rebound on the external canister. I have found that the rebound adjustment has more effect than the damper adjustment, notwithstanding I have had no real problems with them.

The supplied bumpstops are quite soft, therefore you may consider changing to the FCM bump stops. I have and it is well worth the money.

Adjusting the height requires that you loosen off the external canisters, if you don't you could break them.

There is a limitation in how har the car can be raised as the slot the external canister moves in is a limiting factor. Again this would only be an issue if you are going to corner weight the car and put 5mm rake with the drivers weight in the car. I can get the height (at the pinch welds) where this is an issue if needed.

A review on the ER's can be found here http://www.iwsti.com/forums/gd-suspension-handling-stiffening/168885-bc-racing-er-series-coilover-comprehensive-review.html

[zoomzoom]

For the money I couldn't be happier with the BC racing shocks. To have separate bump and rebound at that price is virtually unheard of and a huge benefit for tuning the car handling characteristics.

As far as adjustment, yes the rebound adjustment will have more effect than bump, as with all shocks the rebound does most of the work of damping the springs oscillations. It is important, particularly on the bumpier tracks, that the bump does not over damp the wheel and prevent the car from soaking up the bumps.

For the height adjustment, there is no reason why the spring seat cannot be raised to raise the height of the car the same as you would with a set of shocks that was not base height adjustable. The compressed height of the spring will be the same once the car's weight is on it unless it is preloaded beyond the point which equals the mass of that corner of the car. If the car is using all of the available bump travel (ie. it is on the bumpstops) and there is unused rebound travel then adjusting with the spring seat will also help to move the static position within the range of the total shock travel and gain bump travel.

I currently have mine sitting a little higher than I had done to gain a little extra clearance on the splitter, mind you I have managed my quickest times with it as it currently sits. My shocks have the base height set so the reservoir tube is about halfway up the slot and the ride height at the pinch welds is just over 120mm at the front.

I am fairly satisfied with how the car is at the moment, I think the main things I could do to help on the handling front, is fit wider tyres if I could get them in R specs, and one of these days I'll find the cash to get a proper diff!

Cheers,

Tim

[zoomzoom]

Another point about the coilovers, as with most available for the mazda the ratio of spring rates is way too high, they are supplied as standard with 6/8kg springs which works out to 75% (rear/front). I chose to raise the front rate a little since the car is not street dríven rather than lower the rear rate.

I opted for 10kg springs on the front and left the 6kg springs in the rear which yields a rear/front ratio of 60%, much closer to stock which results in more neutral handling without having to disconnect swaybars etc.

Cheers,

Tim

[corners]

So did you buy any tyres during the xmas break?

[zoomzoom]

So did you buy any tyres during the xmas break?

Not yet unfortunately, the car is sitting up on stands and I have not had a chance to do any of the jobs I wanted to get done before taking it out again (just small tidy up stuff). Also due to some other costs which have come up recently I won't have the money to spend on tyres or trackdays for sometime .

I was planning on just winding back to doing the timeattack series only this year, but at this point I am not going to make it to the first event in March and I am not sure when I might get it back to the track.

Cheers,

Tim

[corners]

So did you buy any tyres during the xmas break?

Not yet unfortunately, the car is sitting up on stands and I have not had a chance to do any of the jobs I wanted to get done before taking it out again (just small tidy up stuff). Also due to some other costs which have come up recently I won't have the money to spend on tyres or trackdays for sometime .

I was planning on just winding back to doing the timeattack series only this year, but at this point I am not going to make it to the first event in March and I am not sure when I might get it back to the track.

Cheers,

Tim

Oh doesn't sound good at all