1994 Mazda RX7

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PorkRind

3,053 posts

205 months

Thursday 22nd February 2018
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As I've said before, countless times, arguably the best looking Japanese car, period.

Pelo

Original Poster:

542 posts

273 months

Thursday 19th April 2018
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Wow, I've owned this car for a whole year now. It has been fun, sometimes frustrating, and very expensive.

Since my last post, I've moved out of the apartment, into a house with a garage, and also have a baby due in July So I want to tick a few things off the list before our lives are taken over by a flatmate we can't kick out for 18 years...

After fitting a lot of new parts in the last post, I went to the Leadfoot festival for a friends stag party. I almost didn't make it after a coolant leak returned. Ever since the first track event at Pukekohe, the coolant level sensor has leaked water under pressure. Just a tiny pinhole leak. The sensor couldn't be tightened as its all plastic, and the head had separated from the thread. So I covered it in gasket goo and it gave no trouble for ages. Then going to Leadfoot, there is a fun road over the hills. I stopped at a lookout, smelt coolant, and discovered the leak had returned. It was bodged and I forgot about it. Damn. So back to gentle driving for the rest of the weekend in Whitianga.

Here are the lads cars.



And the stag himself. Skyline drivers eh...



Leadfoot is a fantastic event, don't miss it!

Then I moved house the next week and Rotary Reunion was the next weekend. Did I have time to order and fit a replacement part? No! Lets try the world's favourite bodge, JB Weld!



It worked ok. Got the car back together late Friday night and cruised to Taupo. No leaks appeared thankfully.

ReUnion was a bit of fun, but it rained torrentially all weekend. So no drags, mediocre burnouts, and risky track driving. I videoed a lot of it but the driving footage is barely worth watching. The yellow Bomex FD is currently my favourite car in NZ!



So the car ran like st all weekend. It turns out the coils I bought second hand were failing at anything above cruising temperatures. Buy cheap, buy twice...

I research upgraded coils, such as the fancy Smart Coil options like this http://www.sakebombgarage.com/ign-1a-high-performa... but I ended up buying new Mazda coils locally. A big hit at $900.



Another mission getting the intake manifold off, replacing the coils for the 3rd time. At least I'm getting faster at it. Now the car runs better than ever! Smooth all the way to redline, smooth idle, faster, and better fuel economy. Here's a quick jaunt down a private road.

https://youtu.be/huayGFSqcvM

By March the JB Weld had begun to leak. Now let's deal with this properly. The sensor disintegrated as I forced it out of the thermostat housing.



New OEM sensor and gasket ready to install.



Much better!



Another few litres of coolant, another hour spent bleeding the coolant system. This is very important on a rotary, as air in the coolant can cause hot spots, which then destroy coolant seals, which then needs a rebuild. A very expensive thing to overlook! This Lisle funnel is a great tool, it makes the bleeding process much faster and easier.

https://imgur.com/oSuhuKm

The factory spoiler has been refitted, I like it just as much as the smooth no spoiler look, but got sick of the rubber plugs. The paint on the spoiler and mirrors is ruined, one day they'll get resprayed.

Here's the car in front of our adorable white picket fence.



Last week I installed the old school Blitz blow off valve. Now my car goes CHOO-CHOO! biggrin It isn't too loud thankfully. In theory it should help with faster boost response, as the factory one is a normally open bypass valve that only closes under boost. I tried running that valve open and it sounded RIDICULOUS. A constant whooshing noise when the turbo isn't boosting, and a very loud CHOOOoooooooooosssshhh sound when shifting on boost.



On the 6th of May I'm going to a track day at Hampton Downs. https://www.facebook.com/events/385654548577468/

Then planning on Chrome again this year, although having a fresh baby may interfere with that...

At this stage I just intend to keep the car reliable and not mod it any further, apart from reliability related upgrades. Oil catch can, water injection, budget intercooler water spray... The list of stuff i WANT to do is huge of course!

So how much has an RX7 cost over one year of ownership? I'm a geek and track every cent I spend on cars in a massive spreadsheet. Here is a breakdown of costs. To be honest it's a shock, and I hope the second year has a better fun to dollar ratio.




Nik da Greek

2,503 posts

150 months

Thursday 19th April 2018
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Gahhhh... those poxy coolant sensors are an utter PITA. So fragile and crap. Worth gunking up the place where the wire enters the plastic nut with some silicone or something, they have a nasty habit of shearing off the wire almost flush with the plastic. You can separate it with a bit of heat and re-solder but they often disintegrate completely during the process.

For future reference, if you can find one for an FB-series RX-7, all you have to do is swap the connector on it for the FD-style one and they're then identical. Except the FD one costs about three times the price...

Pelo

Original Poster:

542 posts

273 months

Thursday 17th May 2018
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Track day!

On the 6th of May I went to an HD Auto day at the Hampton Downs club circuit. I went here last year and it was good fun. It is organised by Hampton Downs themselves and more info can be found here https://hamptondowns.com/hdauto/ 

This time my friend joined me in his 180SX.



There were about 40 drivers and a good range of cars, including a Porsche Cayman, some brand new BMW M6s, a mk2 Escort rally car, a Corolla E70 with a 3SGE, 300ZX turbo, and a Nismo GTR... which got smashed into a wall

A new Impreza and Mercedes turbo thing



MX5 powered by a rotary 13B, na with a carburettor!



This very fast RX7 with a ported single turbo motor, imported from Japan as a track weapon. You could hear it from the other side of the track!



The morning was very wet but it dried up after lunch.



My car with a fair bit of mud on it. I had a high speed spin into the grass (thank the gods!) in my second session. Unfortunately not on camera. I was being chased down by the white RX7 and I was paying too much attention to my mirror instead of my line and balance at 130 kph in the wet... backwards into the grass! There is a lot of run off on this track, the GTR went off at about the only place its possible to hit anything.



I got a new GoPro for Xmas, so of course I've been spamming Youtube with self indulgent driving videos. Here's the one session where the GoPro GPS worked.

https://www.youtube.com/watch?v=jSTwLfBerGg

And a split screen view of a session with the 180SX

https://www.youtube.com/watch?v=VjNs47IZJjI

Before the track day I made up some prototype intercooler ducting using foam rubber, cardboard, and duct tape. It made quite a difference. The stock duct doesn't fit the Greddy intercooler very well so to make it work properly you really need to make a sealed duct. I also experimented with an intercooler water spray but it wasn't much use with cardboard ducting!

I figured out last time that my water temperature and boost gauge can't be seen with my helmet on, so I did a temporary cable tie mounting to the center speaker bracket. 



Sometimes I take my car too seriously. Why not have some fun with a few stickers?



One of the recently printed club stickers! #notoldschool



And a wee Pistonheads Grin sticker 
The car ran perfectly with the new coils, my tyres are still in good health and it was a very fun day out.  I'd like to get some semi slicks and sway bars eventually, the RE003 road tyres do a good job but they are a compromise.

Edited by Pelo on Thursday 17th May 10:50


Edited by Pelo on Thursday 17th May 10:50

Pelo

Original Poster:

542 posts

273 months

Thursday 17th May 2018
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Nik da Greek said:
Gahhhh... those poxy coolant sensors are an utter PITA. So fragile and crap. Worth gunking up the place where the wire enters the plastic nut with some silicone or something, they have a nasty habit of shearing off the wire almost flush with the plastic. You can separate it with a bit of heat and re-solder but they often disintegrate completely during the process.

For future reference, if you can find one for an FB-series RX-7, all you have to do is swap the connector on it for the FD-style one and they're then identical. Except the FD one costs about three times the price...
Yeah its a common problem, Mazda really cheaped out on that particular part. Here's hoping I don't need to remove anything in that area for a while!

Pelo

Original Poster:

542 posts

273 months

Sunday 10th June 2018
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Fun times on the Hauraki plains. Hitting 200+ kph at a Standing & Flying 1/4 mile event hosted by the Thames Valley Car Club.

Hamilton Rd Kerepehi Standing 1/4 & Flying Mile - YouTube

RX7 Flying Mile Sprint - 0 to 200 kph - YouTube

Pelo

Original Poster:

542 posts

273 months

Wednesday 19th June 2019
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Wow it has actually been a year since I updated this blog!

July 2018

At the sprint event I damaged the front spoiler, as the road was very bumpy at 200 kph! It had never looked very good, and had obvious fading and plastic welding marks.
I removed the front spoiler, with many rusted mounting bolts breaking. Thankfully there was no damage under the car. I sanded off all the scratches and plastic welding marks from previous repairs, straightened it out, replaced the mounting bolts and clips, and painted it with spray on black Plastidip. It came out quite well for a first attempt. Much better than the very temporary “black restorer” goo. When the Plastidip coating gets damaged again I’ll do some more sanding to get it even smoother, and try to avoid bubbling.





I also cleaned the filthy front bumper with wax and grease remover, sanded off some old overspray, and adjusted the brake duct fitment. The FD has legit brake cooling ducts below the oil coolers, but they do get damaged sitting below the bumper there.


I have invested in a clay bar, orbital polisher, polish and wax kit, as I need to get rid of all sorts of blemished spots. The paint has been a bit neglected because I don’t really enjoy washing cars. Luckily the red looks great in good sunlight even unpolished. Spot the differences with this fully restored RX7!



Pelo

Original Poster:

542 posts

273 months

Wednesday 19th June 2019
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August 2018.

We are back at Chrome. It was fun, but not great like last year. Too much waiting and traffic on track. The car ran well and fast. The Blitz blow off valve is puffing blowby oil, directly on to the exhaust manifold, and started smoking. I’ve bought a catch can. It only happens on track cornering. One suggestion I’ve read is to keep the oil level around half full, but that is not a risk I’m willing to take!




On the way home from the track I got a lovely golf ball sized dent in my bonnet from a truck kicking up a stone. It probably would have gone straight through my windscreen, so that was some luck I guess.

The headlights, poor by modern standards, have been upgraded to the most expensive halogen bulbs I could find - NARVA PLATINUM PLUS 130. They are noticeably brighter.

Pelo

Original Poster:

542 posts

273 months

Wednesday 19th June 2019
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September 2018

I installed a cheap oil catch can, with “custom” (Bunnings) aluminium brackets and 8mm vinyl hose, plumbed between front turbo inlet and filler vent tube. I’ve kept the PCV valve to intake manifold.
There isn’t much room to fit one of these, I should really get a catch can custom built. A test drive shows nothing coming out of the blow off valve, but it will be more obvious on track.



Pelo

Original Poster:

542 posts

273 months

Wednesday 19th June 2019
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October 2018


I got sick of the ugly gauge mount. I found a guy https://www.draklore.com/ that makes interior pieces for the RX7 and a few other cars. The Drakelore gauge pod replaces the centre dash speaker. It looks good and fits well. This is also a cheaper and sturdier option than finding a rare RE Amemiya steering column mount.





Pelo

Original Poster:

542 posts

273 months

Wednesday 19th June 2019
quotequote all
November 2018

Time for a sound system upgrade! Nothing major, just a kit to improve on the worn out factory stuff. This car doesn’t have the crazy Bose setup like some RX7s, so it’s just a simple 4+1 speaker ‘90s system, that rattles like crazy.

The crusty old front speakers in their bespoke bracket.

With some help from carspeakeradapters.com, the new Sony 6” split component speakers are mounted.

Tweeters are worth having.


The rear speakers are a drop in fit 6x8” Pioneer, and I’ve also fitted a compact powered 8” subwoofer in the boot. The head unit remains the same Sony media player. A cheap and cheerful setup overall.

Pelo

Original Poster:

542 posts

273 months

Wednesday 19th June 2019
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December 2018

A good old fashioned car park motorkhana / autotest / autocross, with the Sports Car Club of NZ.

https://www.youtube.com/watch?v=-ujIRqADY4w




Pelo

Original Poster:

542 posts

273 months

Wednesday 19th June 2019
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February 2019

Instead of going to Rotary REUnion, I did an Auckland Car Club race event. I raced in the Dual and Multi car sprints. This was my first real race meeting. Staying in the pits, talking to actual racers, and driving with legit race cars on track was rather great. I was the only road car in the sprint class, which was surprising. All the other class entrants were racers just getting some extra laps in. So of course I was slowest! (Excuses!)
The day was very hot, at 27c before lunch. The track temp must have been over 50c.
I put some effort into my tyre pressures. Havingi started with F30 R28 psi, they got really slippery and up to 36 even after the practice session.
By the end of the day I had dropped the cold pressure to 25, which heated up to 33F 31R (measured in the pits after a cool down lap).
The car was much grippier and predictable with the lower pressure, plus the wear seems more even. The road tyres don't get as much of those melted lumps and strips.
The Hampton Downs National circuit is so much faster than the club. I was easily hitting 200 on the straight. I just tried to get my lines and braking consistent all day.
My oil catch can works! No more oil spraying out of the BOV on to the exhaust! But the can leaks 😞 After draining it, duct tape saved the day. I’ll need to replace it with a better setup.
Overall I certainly get more driving time at a track day, but this was worth doing.
The engine still has some rough spots. I reckon its turbo related. The boost fluctuates, and I can hear turbo spooling and slowing like an on-off oscillation. It will go away and run normally if I back off for a bit. Time to again look into the turbo control system…

https://www.youtube.com/watch?v=wPhcbMtzh8s

https://www.youtube.com/watch?v=rOgjo0Va-io

https://www.youtube.com/watch?v=2loR8DPZo5M

Pelo

Original Poster:

542 posts

273 months

Wednesday 19th June 2019
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Since then? Not a lot has happened. Just the monthly drive out to the local car show. My daughter is nearly one year old now, and family has taken up most of my time - which has been very enjoyable. I’ve driven only 1500 kms since she was born! Future plans for the RX7 at the moment are unclear. But it’s no worry having it wait in the garage for now.



Daston

6,075 posts

203 months

Wednesday 19th June 2019
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Looks great and red is the best colour!

Speaker set up is nice, mine is still on the originals that are way way past their best!

Our daughter is now 2 and is able to be front facing so she can sit in the front of mine with me. Just trying to work out how to fit a car seat in the back for when child no2 turns up.

Nik da Greek

2,503 posts

150 months

Wednesday 19th June 2019
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When I went to investigate the annoying speaker rattles on mine, I found that the butyl rubber edging on the speaker cones had completely disappeared, leaving only the fibre cones held by the magnet. No wonder it sounded so abysmal eek



Good luck with finding replacements if you need to do the rears too... they're some bizarre unheard-of size like 4X7s, not the common 6x9s rolleyes Becos Mazda

Pelo

Original Poster:

542 posts

273 months

Monday 24th June 2019
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Nik da Greek said:
When I went to investigate the annoying speaker rattles on mine, I found that the butyl rubber edging on the speaker cones had completely disappeared, leaving only the fibre cones held by the magnet. No wonder it sounded so abysmal eek

Good luck with finding replacements if you need to do the rears too... they're some bizarre unheard-of size like 4X7s, not the common 6x9s rolleyes Becos Mazda
My rears were in the same condition! So many rattles! I've replace them with these Pioneer TSA6886R, a drop in fit for a lot of Mazda and Ford cars. They sound ok, fine for rear fill.