1973 929/RX4 Coupe Project
 

So far, I'm just getting ideas for the project, I purchased the car from a guy in Australia and will import it into New Zealand when I finish working offshore in a few months.

Between now and then gives me plenty of time to decide what I want to do...now that I've got the FC dialed in and running Im pretty keen just to keep this as a NA engine and to keep things as original as possible.

With 'Furb's build as some inspiration, it'll be nice to see progress of someone else's build until I get get started with mine.

The car has had all the body work done, and all the chrome is there just needs a little polish...and of course, re-assembly.

Here is a few pics of what she's like...

Engine Package Options
 

First off the list is of decisions that need to be made is the engine package, at this stage of the game I want to keep the car reasonably close to original so with this, I would prefer to run an NA block.

At home I have a Cosmo REW 13b that I was thinking to use, I've got a couple of Mazda new housings stashed away and a pair of high comp FC rotors. As far as porting goes, I was thinking along the lines of just a mild extended port to keep things nice and smooth...as it is, this will be the family sunday car once it's up and running.

The other Option would be to source an FC block but finding decent irons for these is getting difficult and then I'd have to get some housings.

Anyway, what are your thoughts on the engine setup?

One of the things that is nagging me, is the sump setup and the best way to overcome this when running the REW block in the RX4?

Nice find. That should shine up nice.

As for the engine, I'm pondering the same questions for my RX3 build.

So far, the engine is looking like it should be pretty straight forward to mount, from what I understand I should be able to use an old school 13b sump on the REW block but will have to drill and tap a couple of new holes. Will use a 12a front cover and with luck the sump will be fine.

Seeing as it's only rolling on some steel rims, I got to thinking about wheels, after hours of searching, I've comeup with a couple of ideas...

Wheel choices
 

What are your thoughts on the wheels, I've come up with a couple of options, so far I am leaning towards the gold rims...

Stud Pattern
 

Seeing as the 4x110 stud pattern sucks and the choice of wheels is very limited, I started looking into the options of redrilling discs or upgrading hubs.

From people I spoke to and things I have read, redrilling the RX4 discs is not an option, then somewhere I cam across a company call MSF Racing. Here is a link to what they can supply...

http://www.msfracingcomponents.com.a...arycomponents/

This seems to me, to be a very good option, would give me upgraded discs on both front and the ability to put discs on the rear.

That MSF site is pretty cool, I love guys that make shiz like that. Makes life so much easier and looks pretty reasonably priced as well. For engine choice what about a bridgeported NA rx8 motor with a side draft. Combine with a Long manifold or injection to give it plenty of low down torque, and am not aware of any BP MSP motors in NZ yet so would be driveable, unique, would look cool and make the right noise. :)

RX8 Block
 

I hadn't considered the RX8 block, I already have FC plates and a complete REW engine so will go with one of these. The RX8 blocks are getting cheaper now but not that keen on them when compared to the 7 blocks.

you can use RX-7 FB running gear to upgrade to 4x114.3

Renesis is an option. someone i know is working one to find out what it takes to put one in any old Mazda. he is using a RacingBeat inlet adapter plate to bolt an FC Carb manifold to the Renesis. i believe the 12a front cover fits aswell, its been a while since we talked about it.

i am using a S5 TII lump

A couple of small updates...have managed to find some wheels which has set me on a course of 4x110PCD which isn't so bad, have decided to go with FB front struts and GSL rear disc's.


https://cimg5.ibsrv.net/gimg/www.rx7...abf3f069a8.jpg


8" Front's and 10' rears.


https://cimg6.ibsrv.net/gimg/www.rx7...2ec7471d91.jpg


Needs to be lowered a little...

Here is a pic of the car that the wheels came off...hopefully I'll have a similar ride height when finished.
https://cimg9.ibsrv.net/gimg/www.rx7...ae6db67152.jpg

It seems that the only place I can find an IDA manifold for an FD block is from Racing Beat, maybe there is not enough of a market for others to produce them, I guess I'm lucky at least one company makes them!

Trying to find a DCOE manifold is another story altogether! You're probably thinking why would you want to use a sidedraft...I thought...why not!

I like the look of them for a start, I understand the IDA's have bigger fuel bowls for extended WOT but as I'm not going to be racing this car, I thought I would go with something a little different.

I was able to find the IDA and DCOE flanges on ebay so that leaves the fabrication to be done, I am assembling all the parts for this at the moment to send to a fabricators so they can make up the UIM for me, I'm keen to get this together and see how it sits.
https://cimg9.ibsrv.net/gimg/www.rx7...e79f08b2c3.jpg

those wheel look sick what are the offsets....also building an rx4 so i will keep a close eye on this thread....looks good so far.

The offsets are +13 front and rear.

It seems the best route for fabricating the upper intake manifold for the DCO was to use solid works, have a mold printed and then cast...so, it's going to cost a bit more than expected but the flow characteristics should be about as good as I'll get...
https://cimg7.ibsrv.net/gimg/www.rx7...dc71d9189a.jpg


https://cimg8.ibsrv.net/gimg/www.rx7...b0c18542ff.jpg


https://cimg9.ibsrv.net/gimg/www.rx7...2875262693.jpg

that is going to be one cool manifold....im not sure of the cost to make it but there is a company here in the states that makes one piece manifolds. they used to make them for the star mazda race series. i've had a couple and they are really nice pieces...if i remember correctly they are only $100 USD or so.........here is a pic


https://cimg9.ibsrv.net/gimg/www.rx7...240e88c443.jpg


https://cimg0.ibsrv.net/gimg/www.rx7...e7c0e7483f.jpg

here is what it looks like installed


https://cimg3.ibsrv.net/gimg/www.rx7...0d46b63d69.jpg


do you happen to know what mirrors are on the blue rx4 you have pictured?

Thats a nice looking manifold, Atkins produce a similar one but the problem I have is that finding one to suit an FD block is not easy! What is the name of the company that produced them?

Would be interested to find out if they make them for FD engines.

Will find out about the mirrors for you...

The mirrors are from an XY GT Ford Falcon...I don't think you guys in the US ever saw these on your roads...
https://cimg1.ibsrv.net/gimg/www.rx7...5b40014e83.jpg

Papsmagu...where are the engine mounts from in the last picture you posted?

the manifold will not fit the FD engine....sorry i missed that. The manifold is made for a 6 port. engine mounts are from Banzai racing. they are for the FB but they fit our cars just fine. That engine pic is from my REPU but its the same thing on the 4

thanks for the falcon pic and mirror info......you are right.....we did not get them in the US

If you're interested in those mirrors, they are available on ebay.com.au

Slight Change of direction
 

Well, I finally imported the RX4 from Australia to New Zealand, I have managed to set up home finally after working offshore for the last several years.

Anyway...here is a little update...

The change of direction...
 

After talking to a friend of mine and discussing the tune-ability of the 50DCP/SP...I've decided to go with injection.

I'm still going to retain the DCOE but I'm now gone with an EFI Hardware DCOE throttle body.

This particular unit is 52mm inlet bore tapered down to 50mm to match my manifold, with luck the slight tapering will give me some added velocity, then agin when it hits my LIM...it should increase velocity again.

It only has 2 injector bungs so the plan is to run 2 x 1300CC ID Injectors...if this doesn't work so well, I'll use the 2 injector bungs in the centre iron.

The last pic is of the engine bay so far, I've only fitted the radiator which will have to come out again shortly for the engine install.

Engine internals
 

I've had the rotating assembly sent off to be balanced, but I'm now back at sea for a couple of months so until I get home I can't post any pics.

I have an RX8 e-shaft, RX8 rotors with the apex slot machined out to 10mm depp to run conventional seals. Will be using a 12lb flywheel with an ACT pressure plate/clutch setup.

The rotors have been match weighted to within 1 gram of each other...the balancer told me they were well out on weight and took alot of work to get them within 1 gram of each other.

This will be the first time I've used RX8 rotors, so the next thing for me, is to clearance the side seals and for this, I have started to make a jig.

Fueling...
 

A quick little mock up of a surge tank I'll be running, this will have an enclosed Aeromotive Stealth pump.

This will be fitted to the inside of one of the rear wheel arch's.



A few other bits that are ready to go...

An FC gearbox that has been rebuilt and then I had it Vapourblasted, came up like new:nod:

Decided to get the manifolds, alternator housing, and a few other bits done as well.


Rear Garnish, straight out of the box...and the nose cone pretty much complete.