Hellmun's NB8B

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Hellmun
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Joined: Sat Feb 10, 2007 1:15 pm
Vehicle: NB8B - Turbo
Location: Wollongong,NSW

Hellmun's NB8B

Postby Hellmun » Sat Oct 23, 2010 10:50 pm

Well I've been meaning to do a garage thread for some time now but never get around to it. So I'll start off small and add pictures as soon as the gallery comes back on my ISP.

My car itself is a 2001 model which I picked up in New years day 2007. It was immaculate at the time with barely ever a stone chip. It's only modification was heavy BSA 17" wheels with some Sumitomo HTR-Z tyres. Car felt awesomely tight and it only had 35,000km's on it and had been garaged it's whole life. It came with a hard-top as well. Initially it was only to be a trackday car but I drove it everywhere just because it felt sooo good compared to my tired old Camira. I think I did my first trackday by March after less than 3 months owning it for the Mx5 clubday triple treat. This was back in the days when we used to use the short-track, longtrack and hill climb which hasn't been done since Wakefield Park was resurfaced.

I signed up to the trackday in stock class and planning to stay there so I could be a better driver with all the modification variables removed. However... fate decided, or atleast the scrutineers deemed that my wheels put me in modified class. So understandably I wasn't as competitive as I liked. We all like to think we're going to go out and surprise people with a wicked fast time. Well I didn't surprise them with that...I did however spin off the track about 17 times, melt my tyres, boil my brake fluid and rip apart some brake pads :shock: . I spent the next 2 months trying to find some stock 15" wheels to use and oddly not 1 set came up on the forum or anywhere else at the time. First things changed were lessons learnt from the first trackday and advice from CT. So I got DS2500 brake pads, had the brake fluid professionally flushed and replaced with RBF600. I never saw 1" of broth in my master cylinder again past this point :mrgreen: .

At this point I started doing every trackday I could which included Circuit club trackdays at Eastern Creek. My first day there it was really wet and I was pitted with an EVO 9 which I was proudly keeping up with. Towards the end of the day it dried up though and I got more confident. Too confident actually and I lost it on the big hairpin at corner 9 and slid on the grass and was running parallel to the wall backwards at high speed. Managed to slow the car down but it just clipped the tyres and ripped the exhaust up into the back bumper and destroyed the tail-light. So I replaced the tail-light and resprayed the rear quarter of the car.

Rodd Clarke stopped racing by this point and he started parting out his NB8B and he was the current record holder for the road registered non-turbo modified class so I bit the bullet as I'd already ruined an exhaust. I contacted Rod and I got his old SMB exhaust and Racing beat headers. Plus his original Mania ECU which plug-in harness. This was a rare unit and one of the only things at the time that could handle the SVT and work around the alternator issues. There was however one problem and that was the mixtures were horrifically off with my car even though they were the same models. I figured it was simply due to the lack of CAI and contacted Mx5 Mania to see if I could get it retuned. Luckily or Unluckily I dropped my MAF while I was doing some preliminary design for a CAI and this actually broke the hot wire element. Daniel at Mania said he could upgrade the ECU board and firmware and convert it to a MAP sensor for me. So I borrowed a mates MAF and got the car up there and it was tuned and the car got a simple PVC elbow to a Pod filter as a CAI for the time. From memory the car made 87kw atw on the very old mania dyno. This was the last power mod for a very long time. I also picked up some cheap Advanti racing wheels for $100 for some eventual race rubber. They were just 15*6.5 ET38 but were surprisingly light. Next was coil-overs, I did my research and got myself some Tein Monoflex with an EDFC unit and self-installed them. Then I had 2 more changes before the start of the 2007-2008 mx 5 club season which were to change the diff and ratio from my open diff on 3.606 to Babalouies 4.1 centre on a Tomei Traxx 2-way competition clutch-pack LSD. It was at this point my car finally felt like a real race-car and my times came right down. In 6 months I'd gone from a standard car doing 1:23's to a 1:16's. A very expensive 6 months I might add!

Now I learnt one of the more important lessons and this one was from Phil Ashton(Charlie Brown). I got myself some Bridgestone RE55S 205/50/15's for the Advanti's and found I was now going slower (1:18'ish). The car just felt like it was bogging down on corner exit and they didn't seem to be much grippier. He took me for a drive during lunch and absolutely stood on the brakes and really push the car hard. This did 2 things which he probaly regrets now :mrgreen: . Firstly he showed me you can brake REALLY hard on semi-slicks, he practically slammed the pedal and the car just stopped. I'd been made paranoid by a few people that if I flat spot the tyres ($1200 worth at the time) they were ruined. So I'd actually been braking less than on the street tyres and the second bit was he got heat in the tyres because of this...which made them come alive. This immediately pulled 4 seconds off my PB and got me competitive with Irwin8er, Lithium and all the other front running modified guys.

Over the next 6 months during the competition year me and Irwin were always within a few tenths of a second of each other and we both slowly developed our cars to stay competitive. So we'd both try out different mods and basically apply what worked to both our cars. So from here the car got by the start of 2008.
    Front 24mm Swaybar
    Rear 16mm Swaybar
    Polyeurethan bushes
    Brown Davis Rollbar
    Sparco Tec raceseat
    6 point autotechnica Harness
    Flared guards
    Rear swaybar endlinks

From my old spreadsheets I can tell you that including only mods, race gear and servicing I had spent $39269.90 in my first 12 months of mx5 ownership :shock: :shock: :shock:

By this point forward most of the improvements came form me learning to drive but a great many refinements have been made.
    DBA4000 front rotors
    Slotted RDA rear rotors
    Rear race brakes to match the front
    Carbing Front Strut tower brace
    Carbing fender braces
    Carbing front sub-frame brace
    RS-Aizawa rear Strut tower brace
    Beatrush differential Brace
    Mazdaspeed engine mounts

Plus the car now got a re-tune. It was pointed out to me by Phil Mayo if I remember right that my car was blowing a lot of flames/black smoke all over the hill section of wakefield. Me and Irwin8er drove together in convoy to Winton a month earlier and I'd actually used more fuel than him and he was towing a 400kg trailor on his car. So I contacted Daniel and he said he hadn't had much time to do a thorough tune first time round so he'd be happy to clean up the tune for me. This cut my fuel use about %20 everywhere including on the track and the car felt significantly smoother and had more torque at 4000rpm. Where it was tuned it had made 105kw BUT that must've been an awesomely ego inflating dyno because it still was just a little slower than a few other cars on the straights which dyno'd much less. Also on the trip down to winton the car had lost it's pod filter twice on the elbow which was getting tiresome so it was retuned with a modified K&N typhoon intake and home made cold air box.

Since then the only mods in the last 2 years have been
    Air-con removal
    Power steering removal
    Radio Removal
    949 racing 15*8's
    52mm cooling pro radiator
    Sparco Sprint V
    APR Carbon mirrors
    Lightyear Carbon hard-top
    Mazdaspeed pedals

Times the car has done :-
Wakefield Park - 1:09:68
Eastern Creek - 1:52:91
Oran Park GP - 1:23:01
Oran Park South - 53:36
Winton Long - 1:44:92
Winton Short - 1:12:12

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Hellmun
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Vehicle: NB8B - Turbo
Location: Wollongong,NSW

Re: Hellmun's NB8B

Postby Hellmun » Sat Oct 23, 2010 10:55 pm

The future of the car is definitely a turbo. As such I have 2 options which I have the parts for. I have a genuine SP turbo manifold which was machined from a blank 2 years ago. With a Garrett GT25/60R turbo inconnel version, Nissan inconnel stud-kit,water lines and dump pipe. I've got a used SE stock manifold, brand new IHI turbo charger (stock SE unit) plus a bell engineering divided gases dump-pipe and catalytic converter. This lets me make either a 2F turbo or 2B turbo. I've got a set of 4*440CC RC injectors plus a plug in loom for the stock harness.

Also got an ACT chromoly lightweight flywheel which I never installed due to not being allowed in Supersprint regs. Will get a clutch for that for the turbo later.

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Hellmun
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Re: Hellmun's NB8B

Postby Hellmun » Sat Oct 23, 2010 11:06 pm

Here's the fastest lap of Oran Park I did (pretty certain this was 1:23:01).


Fastest ever session of Wakefield Park (1:09:68)


Not a PB but a relatively fast lap of EC which still has many improvements to make (1:53:03).

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Guran
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Re: Hellmun's NB8B

Postby Guran » Sun Oct 24, 2010 5:54 am

Excellent thread Mark! About time too. :twisted:

If I'm late arriving at Wakefield this morning, it's entirely because of this thread :D . And I suspect you might not be an early starter either! :lol:
Standard 2006 NC - YouTube
WP 1:11.89 | SMP-S 1:05.90 GP 1:54.93 N 1:18.09 L 2:22.49 | PW 1:02.52
PI 2:00.55 | W-S 1:12.44 W-L 1:43.36 | SR 1:33.25

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Hellmun
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Re: Hellmun's NB8B

Postby Hellmun » Sat Oct 30, 2010 5:11 pm

Well I got around this morning to taking a look at what was causing my exhaust to rattle so bad. Turns out it was the SMB muffler which had cracked at the joiner between the inlet piping and the perforating internal tubing. Ended up just cutting a window in the muffler, cleaning up the bare metal. Then took a piece of stainless flat bar and wound it around the cracked tubing to use as a round vice/hose clamp on the tubing. Then welded that to the inlet piping (didn't want to weld the perforated tube not having a TIG). So far the car sounds extremely loud and tinny. Just like it used to :mrgreen:

Also edited and uploaded my best session on the Yoko A050's. So far they definitely don't have the fast warm-up of the Kumho V700's but seem to wear extremely well. I didn't even have them beading up and I still managed a 1:10:16 on them so I think they still have potential. Definitely take some wear in compared to other tyres I've used. Being $40 a tyre cheaper than the kumho's if they continue to get better I'll definitely be swapping over to them instead.


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Hellmun
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Re: Hellmun's NB8B

Postby Hellmun » Sat Oct 30, 2010 5:16 pm

My current engine bay. The CAI is a home made version of the carbon SMB intake that plumb's into the foglight inlet. The reason for the duct tape on the airbox is because it kept having the roof blown off it so I know it pressurizes quite well. It's also got the Carbing 3 point monte carlo style STB with the master cylinder brace.
Image

What the car looks like with it's street tyres on.
Image

Rear
Image

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Re: Hellmun's NB8B

Postby honki3rider » Sat Oct 30, 2010 11:16 pm

Damn, you are quick out there. What is your secret? :mrgreen:

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Hammer
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Re: Hellmun's NB8B

Postby Hammer » Mon Nov 01, 2010 12:10 am

Damn, those carbon fiber wing mirrors are sexy. Luv 'em.
H@mmer - 1994 Clubman | 2002 SP
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GO TOPLESS!!!

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Hellmun
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Re: Hellmun's NB8B

Postby Hellmun » Mon Nov 01, 2010 9:09 am

Yeah they're the APR racing ones from 949. They cost way too much for what they are but they have nice tinted convex lenses which give great vision. On the negative they're manual and people seem to love bumping them so it's a crap-shoot everytime you get in the car for whether your going to be able to see anything.

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Regie
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Re: Hellmun's NB8B

Postby Regie » Mon Nov 01, 2010 7:42 pm

Hammer wrote:Damn, those carbon fiber wing mirrors are sexy. Luv 'em.


ahh i got the same ones! Alan they might be for sale soon also :P
MY07 NC, Mazdaspeed Body, Ohlins, Full GWR Exhaust, 17x9 RPF1's, 4.1FGR and lots lots more

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Re: Hellmun's NB8B

Postby evil_weevil » Tue Nov 02, 2010 12:59 pm

I love this car!
Looking for an SVT motor for this:
viewtopic.php?f=73&t=62834

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Hellmun
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Re: Hellmun's NB8B

Postby Hellmun » Tue Nov 02, 2010 6:59 pm

Image

It's dyno run at the mx5 mania dyno day late last year where it made 90kw and 298nm. Funnily a car with less modifications made more power outright (mine came 2nd or 3rd in the N/A class) but nothing even including 2.0 NC's made as much torque that didn't have a turbo on it. It also made that power right to the limiter with stock head/camshafts. Don't think anything was quite as loud as my car either :mrgreen:

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Hellmun
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Re: Hellmun's NB8B

Postby Hellmun » Fri Nov 26, 2010 8:39 pm

New lesson learnt this week. If your car is so loud you wear in-ear headphones as earmuffs everytime you drive it...maybe it's too loud. I took the car in to Pedder to have the alignment re-done and it turns out my passenger rear wheel bearing has gone rather badly. Another case of wakefield-itis but I hadn't heard a thing which left me needing to fix it 2 days before an endurance race :oops: . So I think in future I will be doing one very important thing between trackdays. Driving it to work atleast once without headphones in so I can hear the car properly. So I spent most of yesterday night and this morning replacing that bearing. The rear wheel bearing are a significantly bigger PITA than the fronts. After spending a good 3-4 hours analysing, using a big hammer and then re-thinking the approach when nothing could budge the original bearing... I went to bed. This morning I made up a mount so it could fitted to the press. This was made out of a 15mm steel roundbar and an 8mm steel plate. Using a 40 tonne press the round bar was bent about 25mm before the bearing released :shock:

On the bright side atleast the alignment was unaffected and Daniel Deckers was awesome to get me a bearing at such short notice. Quite incredible how even without really having any big excursions off the track this year the alignment still gets pulled so out of whack. I had 2.7mm toe out on the passenger front and 0.9 toe in on the right.

So for Phillip island to get the noise down I've got a new N*Power muffler in the mail. Combining that with the cat re-installed and I'm hoping it'll be low enough to avoid any noise issues without any real performance impact. It's the same size as my SMB but unlike that muffler hopefully it'll still have some form of packing.

I've also ran a lot of subaru upper engine cleaner through the motor now with an oil change last weekend and it made....no difference. The car blew more fuel smoke than white smoke from the cleaner. I've yet to have to top up the oil on my car once though even after atleast 40,000km of track work the last 4 years so I guess it was in too good condition to get use of it. I also chuck a can of carbi-cleaner through every year so maybe that's why.

Only remaining issue on the car is the side-seals on the diff have started leaking but no-one has any stock in the country... for the wakefield 300 tomorrow I've topped both the diff and gearbox right up. So here's hoping the car will pound round Wakefield %110 for the whole weekend like it did last year. We'll be running the license plates on the car this time as it looks like it'll be the only road registered entry again :mrgreen:

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Hellmun
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Re: Hellmun's NB8B

Postby Hellmun » Fri Dec 10, 2010 7:39 pm

Well it's been a busy few weeks for both myself and the car. The Wakefield 300 2 weeks ago was wicked fun, highly recommend it as it's run under AASA so a supersprint level car can compete. Only things me and Andrew ever had to get were a 2kg fire extinguisher for refueling and a 3 layer race suit.

The 300 is run over 2 days, with lots of HQ, MX5 Vs RX7 plus a bunch of other categories racing on Saturday and the Sunday. With the wakefield 300 practice, qualifying and shoot-out between on the Saturday. Me and Irwin8er were sharing my car for the weekend and it was competing in both the MX5 Vs RX7 category and the 300 enduro. The weather on the saturday was really hot and we were running 2 year old dunlop D03 in 205/50/15 in R compound. Andrew hadn't raced since February and he did well to run 1:11:70 in practice. I did the qualifying and got a 1:11:11 . The first days racing was pretty non-eventful. I managed 9th in the MX5 races and qualified with an 1:11:46 which had us at 20th out of 35 cars. Not bad for what was likely the only road registered car in the 300. The top qualifier was Ric Shaw with an unreal L98 powered FD RX7 which sounded and went incredible. He qualified first with a 1:02:71 :shock:

Sunday the weather changed for the much worse and we got light rain most of the night and it continued during the day. I had gotten sick before we left and I was the worst on the saturday night when I couldn't sleep at all. So Sunday Andrew drove Race 2 and 3 and we swapped to my 225/50/15 A050's. Meanwhile I was sleeping in the car listening to the announcer, by race 3 I stopped sleeping in the ute and went up and watched. Then Irwin knocked another Mx5 who was blocking him off the track with my car! :evil: . Very very minor scraping really with a slight dint in the front quarter panel and some paint removed around the rear wheel arch so overall I was stoked that so little had been done. Though Andrew got to go visit the officials for making that contact overtaking mid turn-9 at wakefield. Was already incredibly weird hearing the announcers who thought that I was driving. Hearing "Hellmun goes for a massive desperate .....blah" over and over while half asleep in the ute and unable to see anything is quite fear inducing!

Last Mx5 race I jumped in to get a feel for the car in the really wet on the A050's and also to wake up properly before the race however only 1 car showed up. So it was me Vs a very fast turbo FD RX7 in Race 4. Was a pretty fun experience when the RX7 fell off the track and I nearly overtook him. Watching all the people along the pit wall having a laugh and cheering was awesome as the FD hurtled away down the straight :mrgreen:

For the 300 itself I jumped in first and the field was packed. I got some really good video as well. I managed to fall off the track 3 times total and Andrew went off about 4 times. We qualified 20th, actually started about 22nd due to some people jumping the gun before the start line and fought our way down to 11th overall. Amazingly with the bad conditions and 35 cars there was no massive accidents and pretty well all the cars seemed to finish the whole event.

Massive thanks to Tim who was our entire pit crew who refueled us in the rain, carried a dodgy radio and listened for signals.

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Hellmun
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Re: Hellmun's NB8B

Postby Hellmun » Fri Dec 10, 2010 7:55 pm

Clutches are terrible terrible things to replace on an MX5. During the 300 enduro my clutch started to feel pretty weak and it was engaging right at the top of the pedal during the Saturday dry racing. It felt fine again during the wet weather racing on the sunday so I left it figuring I'd drive it during the week and see how it behaved and it returned to normal engagement. Then during the clubday last weekend it started letting go again during the regularity so I started to think I must be really low on material and it's overheating during longer stints.

So I ordered a new Exedy HDB clutch through Daniel Deckers and started work on the car monday. Once I'd taken off all the bracing and tailshaft I found that I was leaking gearbox fluid through the tail-shaft seal. So Monday was spent disassembling everything in preparation to drop the gearbox. I only worked on the car from Midday so I spent about 5 hours removing the bracing, tail shaft and PPF. Tuesday I got the all the bolts off with my father except for the top 2 which we tried doing from the engine bay which was a mistake. Then I got the call to pick-up the clutch so headed upto Campbeltown for a 2 hour distraction. When I got back on Daniels advice we tiled the engine as far back as the mazdaspeed mounts allow and attacked the top 2 bolts with a universal socket attachment and 2 massive extensions. It took an incredible amount of force but we managed to get them undone. Then proceeded to pull the box off by about 5pm on Tuesday. Wednesday morning pulled the flywheel/clutch off and it looks like it's really been overheating. The pressure plate metal has turned blue and there were hot spots all over the flywheel and pressure plate. The actual clutch disc looked fine and had a decent amount of material left so I can only assume the pressure plate was overheating and relaxing.

Then proceeded to clean it all up, make up an alignment tool and start putting it all back together. The flywheel bolts were definitely loctited as they smelt horrible an were so hard to budge. Getting the gearbox back in took ages as it barely cleaned the tunnel with the extractors still installed. Then when we finally got it back in the clutch line had been caught and was between the gearbox and back of the head. They overlap so back out the gearbox came which had just taken 20 minutes to get the input shaft to engage :cry:

After another 20 minutes of swearing we got the gearbox to engage again with issue and managed to put the car back together minus transmission fluid (which was supposed to arrive 2 days before by post but hadn't). This morning we ran the old fluid through multiple fresh filters and ended up putting about 300ml of the old fluid with the rest of my last bottle of redline shockproof. This morning I finished installing the bracing and thankfully the clutch actually worked :mrgreen:

I drove it to the petrol station and it feels so much tighter and well put together. I guess some of the bracing had slackened so I can't wait to drive it down the PI now. Though I would've liked more than 1 day to test the car properly before driving it this far...

Meeting up with Guran tomorrow morning and we'll head down. I've installed the tow-bar and have a small trailor with my race rubber good to go. Just finished packing clothes, eski and some food now. Hopefully PI will be fun and have as little rain as possible. I'd really love to get the car under that magic 2 minute mark and hopefully even further.


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