Rx7 Convertible - FC3C

[stu_irwin]

Thought I start a build thread for my new car.

My brother is rotary mad and now has three FC Rx7 at home in Ireland and mountain of spare parts.  After a drive in them i was hooked, I had to have one!!

Picked this up in April this year from \'rising sun\' a member of this forum. Its a 1991, RX7 FC Turbo Convertible, Japanese import.

Apart from being the rare import convertible, it has also had a full respray, new roof and engine work carried out by WGT.





The car came with Ohilns Adjustable Damping Suspension, Kakimoto exhaust system and aftermarket steering wheel and handbrake setup.

 

The Exhaust was the first thing to go!!  It put out huge flames but it was crazy loud so it had to go before the ASBO arrived!

Fitted a nice custom system. Great sound and still flames if your pushing the car on!




Next on the list was wheels.  I really wanted a set of Regamasters.



But this didn\'t work out so im going for a different look. My inspiration -



Bought these 1980\'s OZ Vega three piece alloys, currently refurbing them.






Need to decide on a colour for the centres?   Keep them gold or   -



I took the RX7 back to Ireland at the weekend, for some suspension work, good clean and a Mazda owners show.

 


At the show beside my brothers UK FC3S

[grinder]

looking good

i cant tell if its a "ring" sticker on the front bumper , or paint missing

If its paint missing , i have the same problem , pushed the car too far onto a trailor and hit the jockey wheel handle .. doh !!

[grinder]

i like the elec fan conversion , looks like there is sooooooooo much more room in the engine bay

[m1tch]

Oooo its a series 4 engine so lower compression, perhaps think about fitting a series 5 turbo to give you an extra 20bhp boost

[stu_irwin]

m1tch -  thats a good point !

We thought it was just a series four radiator that had been fitted?

How do you tell if it is a series four engine or a series five?

Is there pros / cons of each?

[m1tch]

The intercooler says \'Rotary turbo with intercooler\' which is series 4, below is a photo of a series 5 engine intercooler ie the turbo II - everyone in the UK got confused when their first turbo rotary was a \'Turbo II\' as the series 4 turbo wasn\'t ever sold in the UK lol



Series 4 engine - lower compression rotors, less powerful twin scroll turbocharger - it will have an actuator on the exhaust manifold - power is around 180bhp
Series 5 engine - higher compression rotors, more powerful turbocharger - no actuators - power is around 200bhp

Best aftermarket setup to use:

Low compression series 4 engine + larger turbo - the lower compression really does help with turbo applications, I think Mazda upped the compression slightly due to when you are off boost its an EGI, so the increased compression gave a bit more low end power.

[Kodiak]

oh Mitch! What\'s with the heinous pistons!?
 
Stu, that\'s a nice cabriolet you have there. Cool that you and your brother both have FC\'s

[m1tch]

oh Mitch! What\'s with the heinous pistons!?
 
Stu, that\'s a nice cabriolet you have there. Cool that you and your brother both have FC\'s

Google image shot lol I posted it up and thought...GAH! get away! lol

[stu_irwin]

Thanks m1tch,

Is there any way of telling if this a full series four rx7 or if the series four engine been fitted at some point?

I can get my hands on some series five parts, is the turbo the only worth while up grade or would the Turbo II intercooler be a benefit aswell?

Sorry for all the questions but i really don\'t know much about rotary engines and the different versions.

[m1tch]

The intercooler should be the same, just with a different sticker, the intercooler is fine for the stock turbo but becomes an \'interwarmer\' at higher boost levels.

The very very very first thing I would do is to check what ECU its running on, as it jap spec it will be mapped for 100RON, we don\'t have 100RON as normal fuel so ONLY use high octane 99 RON fuel or V power in the car otherwise you might have engine issues - have seen a few people have the engine detonate on them when they put in 95 ron supermarket petrol into their jap import lol

Looking at the engine bay it seems that it hasn\'t really been touched and is all original, its usually just the short block that gets dropped in and not everything else lol

I would check out this site which has loads of tips and tricks as well as guides:

http://fc3spro.com/main.html

Some of the info on there is getting a bit old, but most of it is still spot on

Firstly before you do anything to the car answer the following question:

What will I be using the car for?

Once you can answer that then we can advise on what the best route of action is

p.s. I see you have met with the Kakimoto red label exhaust - thats a small Kakimoto btw

[stu_irwin]

I have broken the first rule of RX7 ownership !!!

Its my only car, so could be classed as my daily driver.

However I get the train to work, so I only really use the car at the weekends.


I\'m really enjoying having a nice, reasonably quick rotary and don\'t think I need
(or can afford) to go for any big power or expensive conversions.


Main aim at the moment is to keep it running, continue to tidy it up and enjoy the rare sunny days.

I do however have spare series five turbos, which could be fun!

[m1tch]

Prof has a convertable as his daily - he is currently rebuilding and reshelling it due to the amount of miles he has done in it.

I would get a compression test done first though to check the health of the engine, you can\'t use a piston compression checker you need a proper rotary checker, the Mazda main dealer will be able to help you out, doesn\'t cost much but will give you an indication of how the engine is.

Remeber that these are not new cars so certain parts of the car will be starting to show their age and not work as well as they did when they were new. It is usually the ancilaries that take out an engine rather than the engine itself.

I would suggest changing the HT leads over to some uprated leads, change the radiator for a new higher volume one and also do a plug and oil change.

Also make sure you warm the car up properly before driving it and don\'t use it for short trips - I let my FC\'s water temp needle get to the \'C\' on the gauge before driving it and not accelerate hard until its sitting half way up and stable. All previous owners of my car have done this and the compression on the engine is still very very good even at 86k miles - should be good to easily get to 150k miles.

One useful thing I have added to the car is a \'fumoto\' oil drain valve, it replaces the sump plug with a tap which makes oil changes really easy to do. I don\'t even need to jack up the car to change the oil - its changed every 3k miles. Also not that the car uses a total loss oil system, people complain that they burn oil.....its ment to burn oil, its an issue if it doesn\'t lol so just keep checking the oil and fluids.

Please also note that another issue that mine has is a leaking power steering cooler pipe - the pipe is located at the front of the car infront of the radiator, it can corrode where the clamps are causing a leak, which in turn sprays the radiator with PS fluid so all the muck sticks to it lol just to be aware of that

I have a spare series 5 turbo as well as a T04 60 trim compressor housing and blade - it will be able to be put together to make a hybrid turbo pushing around 400ish bhp.

Something else to note with regards to the stock setup - 0.6 bar of boost is standard, the most you can push the engine to is 0.9 bar - the turbo, fueling and intercooler are maxxed out at 0.9 bar and will make around 280bhp ish, the injectors aren\'t new so be very careful if boosting up, I would suggest you service and upgrade the supporting parts first and get it driven as a daily so you have a good base to start with.

If you have any questions just ask

Things to also note with regards to engine failures:

Engine overheats - water seals go - soft seal rebuild needed ~ £400 if DIY
Engine goes lean on boost and detonates - tip might blow, rotor hits housing, rotor and housing trashed - new housing and rotor needed plus all new seals - thats the expensive rebuild.

Basically make sure the engine doesn\'t over heat or run lean on boost and it will be fine, you should also red line the engine once warm once a trip - with the added benefit of the higher the RPM, the more the apex seals seal and the more power you make lol

[turbointhebrain]

Ha there\'s my bro!! i wondered when you were going to do a write up. suppose i cant really talk, havnt updated mine in over a year!

mitch good run down lad.

mitch i had a good look round this engine, its defiantly a series 5 engine. has a series 5 turbo, MAF (series four one is the flappy type one you would see on a 6port n/a or an mx5), wiring loom, and the series 5 top water pump pipe... you know the plastic type that can crack.  the series 4 one is different and have alloy unit with cap, again like the s4 n/a. see pic below



you could be right about the intercooler as we can see from pic.  i just personally thought the JDM fc\'s had theis variation of words and the uk their way. could be wrong though

[m1tch]

Still an FC so thats goooood bigger popups and those FDs = win :rollin

[grinder]

yeah the JDM have different words on the IC