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PostPosted: Tue Feb 11, 2014 8:21 pm 
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Hi All,
I'm after a complete relatively recent LPG system including 50/55 litre tank to fit to a Mazda RX8.
It'll need a min 200 hp reducer and 4 (at least) fast injectors.
I don't mind if the kit is for a 6 or 8 cylinder as I may have a use for the extra channels later.
I live between Milton Keynes and Oxford so can pick up if the price is right.
Anybody got anything they want to move on?
Thanks
Julian


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PostPosted: Tue Feb 11, 2014 9:37 pm 
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Something tells me you don't quite know what you're doing here... Without a bit more knowledge you may very well buy inappropriate parts - especially for the RX8.

On most ECUs you cannot leave channels unused. Most ECUs will report a wiring issue and not allow running on LPG. What were you thinking of using the channels for later? It is hard to think of an application, especially since even if the ECU allowed you to leave channels unused for the time being when you later came to try to use them for something else they would be subject to the same map as the rest of the injectors.

You need a reducer with over-kill, if the engine is 200bhp a 200bhp reducer won't be good enough.

You cannot fit just any injectors on that Wankel engine. You will need to fit injectors that flow really well and linear injectors will be a big plus. They will be opening and closing at up to 4 times the frequency given the one shot per rev nature and higher rpm nature of the Wankel engine compared to normal 4 stroke engines. 'Fast' injectors are not always fast - you need to be clear on this. The term 'fast' usually denotes 3ohm coils, this distinguishing the later (with reference to around the year 2004) injectors from the older higher impedance coils fitted to basically the same injectors by the same manufacturers of the older higher impedance coils. The lower impedance 3 ohm coils flow more current so effectively have a stronger electromagnet to open the injectors but this tells you nothing of the other physical characteristics of the injectors. Most injectors have 3ohm coils so could be called fast but often they are not fast in response like you might expect given the designation. You could fit 4 injectors and set them up so 2 injectors fire together, using all 4 channels on a 4 channel ECU so as to avoid reported wiring issues, but if you try this with the wrong type of ECU you will find the injectors are fired in the usual 1342 pattern as opposed to 2 at the same time.

If you are unfamiliar with LPg installs, and I must say you seem to be, then you are looking at potential problems and wasting money trying to buy a second hand set of bits to install on the RX8.

The Wankel engines need special consideration when it comes to converting them to LPG, before you convert a Wankel you need some good advice and/or experience along with a healthy dose of lateral thinking.

Simon
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PostPosted: Thu Feb 13, 2014 10:55 am 
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Hi Simon,
Thanks for your input.
Can I put you straight on a few points?
The reason I was looking at a Stag controller is because an 8 channel controller allows you to use between 3 and 8 channels with no errors so it can be retro fitted to a 231 (6 injector) at a later date.
LPG Tech and Stag can also be configured for rotaries.
Looking at Polish LPG forums they have had success using OMVL, Hana and Barracuda injectors (but not Red Valteks) on the 231 conversions I have seen.
Due to the small amount of time available for injection on my 192 (7500 rpm and 4 injector) of about 13m/s I was looking at batching the injectors for each rotor set (1 and 2 for first stage and 3 and 4 for the second stage above 5000 rpm depending on throttle position) to reduce the injection time of each injector to get enough gas in while still using sensible size injectors for a smooth idle etc.
I have sourced a LPG Tech controller, Hana Blue injectors and a Tomasetto Achille reducer and was going to use 8mm pipe from the tank to the reducer.
I still need to look at the injectors but what do you think of my plan so far?
A 231 was converted using an Egas system a few years ago (these systems are universally slated) so it must be relatively straightforward with the ability to configure the controller for a rotary.
Although there are examples of converted RX8’s in this country the information on what was done is sketchy and I’m sure that how successful my conversion is would be a benefit to all as I only see setting up being more problematical than for a piston engine.
As you know the fuel economy of the RX8 is a barrier to most along with the scare stores that surround these fantastic cars brought on by poor maintenance/knowledge of how to look after/drive them.
For a modern car they have no inherent problems apart from engine issues, which realistically, are easily remedied.
Cheers
Julian


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PostPosted: Thu Feb 13, 2014 6:41 pm 
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Hi Julian,

When writing the post I didn't bear the subject line in mind, my mistake sorry! Thought you were just after any second hand bit of kit for the RX8... That wouldn't have been a good plan but your plan is looking good.

Reckon you'll get good results with the system you propose but I'm not sure I would necessarily use the stepped injection - I'd definitely have a play about with the stepped injection but would anticipate likely not using it due to a lump in the fueling as the secondary injectors kick in.

Not many people rate the Egas system, myself included, among other bad points it has very limited calibration abilities but was supplied with Matrix injectors which are fairly quick performers. The Hana injectors you'll be using are quick and you'll have much better calibration abilities with your choice of ECU.

Are the engine issues on RX8's, rotor issues etc easily remedied?

Simon
Lpgc

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PostPosted: Thu Feb 13, 2014 10:19 pm 
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Hi Simon,
Yes I plan to experiment with the injector grouping to find out the most effective solution and will keep this site updated as to my progress as this information may be useful to others.
I was looking at RX8’s last year as they were so cheap but was put off by the usual scare stories on the net before investigating further.
The rotor tip failures are not necessarily the cause of the usual hot start issues but can be caused by:
Starter knackered as the rotary needs at least 200 ish rpm to start from hot (starters are knackered by people generally flooding them and then hanging onto the starter to unflood them for minutes at a time). Mine was completely f*****.
As they are not so good on fuel people don’t drive them hard enough and this causes them to carbon up which causes rotor tips to stick/carbon build up on housing leading to low compression etc.
They need to be driven hard but have regular oil changes (say every 5000 miles or so) using a mineral 10W/40 not the 5W30 synthetic Mazda recommend. This synthetic oil again adds to the carbon build up as it’s not designed to be combusted from the oil injection used to lubricate the tips. People generally premix them with 2 stroke at a 200 to 400:1 ratio.
They can also suffer from knackered main bearings from using the recommended oil as it’s too thin (used originally to reduce friction/emissions). The RX7 uses intrinsically the same engine and doesn’t suffer from main bearing problems as it always used 10W/40 mineral oil and they’re turbocharged with a lot more power.
The engines themselves are easy to rebuild (look at Rotary Rebuild on Youtube as this goes through the whole process with about 5 hours of videos!).
In a rebuild seals and gaskets have to be changed but the rotor tips (Apex Seals) and side seals can be reused if they’re not damaged/worn out. Housings and rotors are available reasonably priced used. An engine could be rebuilt I reckon worst case for about £1200 and this would have been totally f***** and if the oil changes and type is used etc etc the engine is very reliable.
They were cheap last year but this year even cheaper. I paid £400 for a Nov 2005 car which is Mot’d till July, is in great condition inside and out (they usually are) and are well specced and low mileage. It didn’t start from hot and had a noisy clutch spigot bearing. With an uprated starter it starts perfectly but I am changing the rear main bearing while I have the gearbox out to change the spigot bearing. This just unbolts along with the stationary gear. They are also fantastic to drive, sound brilliant (like a 2 stroke inline 6!), handle superbly (LSD standard, carbon fibre prop the list goes on) and with LPG should do the equivalent of about 35 mpg and really are a bargain if you know what to look for when viewing one.
Put it this way mine is not going to owe me even £1000 with the Lpg Kit and 6 months road tax. How much is the equivalent and nowhere near as good Audi TT?
Also due to the number being broken for supposedly knackered engines (the Mazda dealers were/are hopeless) used spares are for nothing and they have none of the modern car syndrome faults (electrical/electronic/control modules that cost a fortune to put right).
Lpg’d it really is a no brainer if you can get one that has good compression and doesn’t knock and they are out there. Most of the owners haven’t got a clue!
Cheers
Julian


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PostPosted: Thu Feb 13, 2014 10:48 pm 
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I'll agree with just about everything you say. A girlfriend of mine bought a brand new 231 in 2007 and with only 90 miles on the clock we set off to drive it to Pisa in Italy. They go like stink, sound absolutely gorgeous (especially if you drop it down a couple of gears and boot it through the 100 or so tunnels from the French border to Genoa) but we managed to average only 19 mpg over a 2,500 mile holiday. The 231 is redlined at 9,000 rpm but beeps at you when you hit 8,500 to remind you to change up! The only thing I found was that if you are pootling along behind a truck and want to pull out to overtake a bit quick, you need to drop down about 3 gears! The almost total lack of power below 3,000, a reasonable amount between 3 and 6,000 but it has to be over that to get it to really shift! The 231 comes with a 6 speed box and 13 speaker Bose sound system too....

The way it drank the horrendously expensive synthetic oil was a downside but you've answered that one and my only other criticism would be that the panels appear very thin. The lightest touch in a car park put a very noticeable dent in one of the doors. They drive and handle very much like a Porsche 944 Turbo but you won't get any change out of £4k for one of those and that will be for a 22+ year old car. I doubt an RX8 will last until it is over 20 years though.

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PostPosted: Thu Feb 13, 2014 11:34 pm 
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Hi,
No I dont' think longevity of body panels is is at the forefront of Japanese thinking.
There are already a few earlier cars that have been scrapped due to rot. At least the bonnet and suicide doors won't rust as they're Aluminium so probably worth a bit in scrap on their own!


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PostPosted: Fri Apr 18, 2014 9:44 pm 
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Joined: Sat Apr 05, 2014 10:22 pm
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Hi Ziggy

Are you looking for a new set or used?
Do you need receipt?
I got Ecu with OBD, reducer and injectors, maybe tank as well but give the measurement or if you already know the size of the tank you need.
Peter
My mail.
sensitivegentleman@gmail.com


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PostPosted: Fri Apr 18, 2014 11:52 pm 
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thegentleman wrote:


Did you make that email address for another website? :lol:

Simon
www.Lpgc.co.uk

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PostPosted: Sun Apr 27, 2014 3:49 pm 
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Which one exactly?
I got lots of emails and this one is really old but still hardly any spam. So I keep using it.
Peter


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PostPosted: Sun Apr 27, 2014 5:17 pm 
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thegentleman wrote:
Which one exactly?
I got lots of emails and this one is really old but still hardly any spam. So I keep using it.
Peter


Si is referring to this 1: sensitivegentleman@gmail.com

are u the guy that works for lpgshop per chance?

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PostPosted: Mon Apr 28, 2014 12:48 pm 
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john_d wrote:
thegentleman wrote:
Which one exactly?
I got lots of emails and this one is really old but still hardly any spam. So I keep using it.
Peter


Si is referring to this 1: sensitivegentleman@gmail.com

are u the guy that works for lpgshop per chance?


It also reads like an email address that might put ladies on certain websites at ease :wink: Maybe that's where I went wrong with my old psychosime999 email address :lol:

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http://www.Lpgc.co.uk
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07816237240


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