Author Topic: Mx7? rx5? Newbies build thread begins  (Read 21984 times)

Offline Steve-A

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Mx7? rx5? Newbies build thread begins
« Reply #30 on: May 10, 2010, 08:04:58 PM »
I had a day off work today, so Ian popped over and we made good progress on the 5.

This is how the day began, stripping more of the ancillaries from the 1.6




Then lifted the 1.6 out.




Big space in there! Then out came the gearbox



And in with the rx7/mx5 hybrid box. The clutch slave worked out just nicely, with the flexi line running right to the end of the mx5 hardline.




Then just to gauge how much work has to be done we dropped in the dead 13b I\'ve got, stripped right back.




It looks like its not far off, but its got not sump on there, and is sitting on the steering rack.

Next up is to revisit all the threads by people who\'ve done this before and do some serious thinking ready to get the fabrication work done. I may well have the transmission tunnel lightly modded to make room for the clutch slave so I can lift the front of the box up a little.

Hmmm, lots to think about!
1984 Rx7: Gold. Edging towards roadworthyness!

Offline kiwimazda

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« Reply #31 on: May 10, 2010, 10:52:01 PM »
How is it looking for exhaust clearence with the steering?
Cheers
Brian

Offline Steve-A

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« Reply #32 on: May 10, 2010, 10:56:47 PM »
errr not great! Where there\'s a will there\'s a way and all. The exhaust route is gonna be quite tough generally as the mx5 exhaust exits on the other side of the block, so there\'s more space to the otherside of the prop.

Having had a good read up this evening, I think the next step is to pull the interior, as its looking pretty likely that I\'ll need to take a chunk out of the transmission tunnel as it enters the engine bay, to allow me to lift the front of the box for steering rack clearance.
1984 Rx7: Gold. Edging towards roadworthyness!

Offline Steve-A

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« Reply #33 on: May 12, 2010, 10:06:27 PM »
Now you see it:



Now you dont:




Only a bit more to go, then I can start cutting :s
1984 Rx7: Gold. Edging towards roadworthyness!

Offline Steve-A

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« Reply #34 on: May 16, 2010, 11:48:09 AM »
Another few days gone by and a little more progress.

Yesterday morning I dropped the box and, with some help from Ross, we started to cut the notch in the trans tunnel that was needed to lift the engine up off the steering rack.





So we\'d cut a hole to clear the clutch slave and top of the box as it enters the engine bay



but as we lifted the box up pas the normal position it started to catch on the top of the tunnel further down :( So the grinder came out again, and we carried on cutting till it fit! As you can see we only need a few mm of extra clearance. Its a shame its resulted in so much more welding being needed.



And the end result....




Much better. :)

I was going to try and use the standard FC engine mounts and modify the sub-frame to take them, but having actually got the engine in the car I think its going to be much easier to follow the way most americans have done this swap and to source a 12a front cover and use the front style mount. This will also give a little more exhaust clearance, which will be very useful.

So cant really go much further till I\'ve had the trans tunnel welded up and sourced a 12a front cover. Then I can get on with the sump and oil pick-up.

In the mean time my turbo II CAS and coil packs have arrived so I\'ll start making the modifications to my megasquirt needed to run the rotaries ignition.
1984 Rx7: Gold. Edging towards roadworthyness!

Offline rossonza

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« Reply #35 on: May 16, 2010, 03:01:11 PM »
really enjoyed yesterday... even though Steve did all the work :)
Just hope you get hold of a 12a front cover soon and we can sort all the sump clearence stuff. Going to be a very cool next few weeks.
email @ rossonza@gmail.com
1984 FB series 2 in gold

Offline kiwimazda

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« Reply #36 on: May 16, 2010, 09:54:56 PM »
I have 12a front cover/s
sellabitnz  @   yahoo.co.nz  

remove the spaces
drop me a line
Cheers
Brian

Offline jpc

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« Reply #37 on: May 24, 2010, 11:13:16 AM »
Quote from: Steve-A;692260
Hi Clive, Unfortunately its not the first one on There\'s a guy on the mx5nutz forum who\'s having an renesis fitted by WGT right now, so I might not be the only one but one of three isn\'t bad


That\'s my \'94  being done by WGT, hopefully at the finishing stages now for delivery mid-June.

I also wanted N/A after driving a twin-turbo FD and supercharged MX5s for 15 years.

From my research, it was going to be hard getting more than 175bhp out of a 13B N/A without compromising driveability so I went for the 13B-MSP Renesis (~230bhp) which has larger ports than the 13B from the FD and also has the fancy intake system. The shallow sump of this engine should also help with clearance since the rotary has to sit so low.

Lessons from this build are:

1. Major mods required to subframe
2. RX8 box mates up to MX5 NC 6-speed tail housing to get PPF on the original side. Gear level is 12mm out from original position.
3. Engine interfered with power steering rack (mine is LHD) so now manual steering.
4. Custom PPF and prop-shaft
5. 2.5" custom exhaust used although still expecting to use an off-the-shelf back box. There isn\'t much room to fit the exhaust manifold so a custom one was made. No cat required on a pre-95 import.
6. No change to diff assembly
7. Rotaries generate a lot of heat, need a good rad and oil coolers
8. A/C removed


The car is stil being worked on at WGT if you want to take a look.

Jon.

Offline Steve-A

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« Reply #38 on: May 29, 2010, 07:18:19 PM »
Well its been a fairly quiet couple of weeks. I was hoping to get the car away to have the transmission tunnel welded up and the engine mount started on last weekend but the welder guy I\'m gonna be using had hurt his back.

So in the mean time I\'ve fitted the 12a front cover (thanks Kiwimazda!) which will mean much easier fabrication of engine mounts.



I then refitted the front suspension, and this morning took the engine and gearbox out, ready to load her onto a trailer tomorrow and go for welding monday morning.



With a little luck all the trans tunnel welding and fab can be done on monday, then I can refit the interior and free up some space in my bedroom! If things go really well hopefully we can start on fabricating the engine mounts. Once the engines mounted securely then hopefully things will really get a move on and progress will speed up a bit :)

I\'m really missing driving this car, driving the Fiat is killing me :(

While I had some time with nothing to do on the car I took the old 1.6 lump to bits and I found a hell of a lot of coked up crap. Think I must have been getting some pre-ignition. Not too much signs of detonation though, which is good :)



I also made some progress with painting my bike, and got it MOTed, which means I can get some lean angle on the go again :) Just need to do the side panels now

1984 Rx7: Gold. Edging towards roadworthyness!

Offline Steve-A

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« Reply #39 on: May 31, 2010, 07:42:18 PM »
Not really feeling awake yet, dad and I left at 6:30am tis morning with the 5 loaded up on a trailer.



By 7 the mx was safely tucked into a workshop and progress was being made!



Very kindly Bill, who works with my Dad, had offered to help me out with the fabrication work on this build. I\'m confident I\'m in safe hands!

4 Hours later, this was the result. A fixed up transmission tunnel, with fresh bracket for heat matrix, and clearance for the rx gearbox.



We left him my spare subframe and some measurements to make up the engine mount, hopefully to be completed in some spare moment during the week. So back home Ian, Ross and Dan turned up to help me get the car back up the steep drive to its home. We then removed the front suspension and subframe once more, ready to receive the modified subframe and applied some paint to protect the fresh metal in the trans tunnel.




Next up is the interior back in over the next few days :)
1984 Rx7: Gold. Edging towards roadworthyness!

Offline Steve-A

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« Reply #40 on: June 04, 2010, 08:29:20 PM »
Another friday off work ( freelance work has its advantages!) and a lovely day to make some good progress.

First thing, mx5 interior:



... back in the car:



Just the center consol bit, glove box and radio panel to go. There\'s no point putting them back till I\'ve finished off sorting out the megasquirt wiring under there. Gonna need to run a couple of extra cables through for the rx7 coils and crank angle sensor.

Then at lunch time I went to pick up this:



Drilled some holes and the engine is in its final resting place! :D:D:D




Plenty of room underneath for the sump and oil pick-up. Just held the oil pick-up in place to show how the sump is gonig to have to wiggle under the engine.



Will start cutting up my spare 13b sump, and get the cardboard and tape out either tomorrow or sunday and hopefully get it made in metal over the next week or so.

Hopefully gonna stop by a local place that does custom exhaust fabrication with some pictures and info tomorrow, see if they are game to help. Will also order a large capacity aluminum mx5 radiator in the next day or two then I can start working out what bits of hose I\'m going to need to build the cooling system :)
1984 Rx7: Gold. Edging towards roadworthyness!

Offline Steve-A

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« Reply #41 on: June 11, 2010, 07:50:05 PM »
Another week gone by and some more progress.

Earlier in the week I drew up the plans for my sump. I was hoping to mod the 13b sump, but in order to minimise the cutting to the subframe this was looking like an impossible task. Luckily Bill, the guy who\'s doing my fabrication work, is rather good at creating complex shapes from flat plate so a fully custom sump seemed best. He tacked it up today, so will pick it up tomorrow morning and check it fits before final welding.



I also stuck some paint on my engine mount.



I got a nice parcel arrive this morning. It was the Racing Beat DIY manifold kit I had ordered from the nice people at Mazdarotaryparts.com. I kinda wish it was what it says on the box though....




I had a chat to the exhaust shop in the week, and despite looking pretty scared when I showed them the pics and dimensions, they then said \'it\'ll be tricky, but its not the worst one we\'ve done, be about £900+VAT" so thats alright. Not too bad a price for a complete system including a very complex manifold.

So today I spent most of the day starting to prepare the good 13b to go in the car. Its a million times cleaner that it was this morning, not that its anywhere near perfect now! In he process of stripping the block down I found this anomaly...



Looks like it must have been rebuilt at some point, and looks to have been built from 2 front rotor housings :s Oh well seemed to run alright in the car, so I\'ll take this as good news that its been rebuilt sometime in its life, so that means its probably got a few miles in it yet.
1984 Rx7: Gold. Edging towards roadworthyness!

Offline Steve-A

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« Reply #42 on: June 18, 2010, 07:34:44 PM »
Didn\'t get much more done last weekend as my \'reliable safe option\' daily driver died. Apparently Fiat saw fit to use a differential in the Punto thats only held together by friction fit on splines, no retaining C clips or anything nice like that. Mine had come to bits, so I spent all weekend ripping in out of the car and hitting it with a big hammer till it was back together....




I\'ve been spending every spare hour I get working on the mx, since I last posted I have cleaned up the gearbox, especially the shifter turret which I took to bits and cleaned properly. It was amazingly dirty for something thats meant to be sealed! I\'ve also made a start on the loom. I\'m trying to do all the stuff that goes by the gearbox first, so done neutral and reverse sensors, starter motor and while I was on starter motor it made sense to do alternator.



Today I picked up my sump and extended oil pick-up from Bill. Its a work of art!





I\'ve spent most of the afternoon fitting the sump to the block, I needed to drill the mounting holes myself, and beginning to build up the engine. As you can see I\'ve got as far as the alternator! The inlet manifold/throttle body is all built up but will be left off to make it easier for exhaust guys to get in there.



Now all the gearboxy stuff is done the plan is to put the engine and gearbox in for good tomorrow and the continue with the loom and cooling system. Once I\'m happy the box wont have to come out again I\'ll get the front suspension back on :)
1984 Rx7: Gold. Edging towards roadworthyness!

Offline antnicuk

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« Reply #43 on: June 18, 2010, 10:57:18 PM »
there is some really good work on this thread,  well done,   that sump is certainly a work of art,   you have a very good contact there.
you obviously have skills and are a bright chap,  would you not want to have a crack at the exhaust yourself?  you could save yourself a fortune.  buy several 2.5 inch bends from someone like burtons or the fella that gave you the price to make it and buy a cheap mig welder (gasless will be fine)  you can cut up the bends and make the exhaust as you want it and just tack it with the mig,  its really easy,  then use a couple of slip joints (which the exhaust bends will have swaged ends to enable this) and take it to your mate to weld up.

I have a kit car with a turbo II engine and its great fun but i fancy an mx5 as my next project.  

Plan ahead as i guarantee you will want a turbo soon!
400 BHP - 650 KG\'s = 616 BHP Per Ton of Rotary Power

That\'s the way to do it! :Thumbsup!


Offline Steve-A

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« Reply #44 on: June 18, 2010, 11:20:30 PM »
Yeh, I had considered trying to do the exhaust myself, but then its really really not gonna be an easy one! The underside of the mx5 is based on an exhaust leaving on the passengers side of the block, but the rotary exhaust leaves on the drivers side. The steering rack leaves very little room for the exhaust to exit then it has to bend round and under the gearbox whilst staying tucked right up under the car, because I\'d like to keep my current ride hight and ground clearance.





All in all I\'ve had a cheap build so far and its worth spending the money to get the exhaust done right I think. Learning to weld is high up on my agenda though!

Turbo maybe, I have to admit I\'m more tempted by the idea of drilling some big holes in the rotor housings.... ;) The main reason I\'m doing this build is I wanted throttle response and driving experience over pure power. I\'m sure I\'ll be tempted back to power......

Mx5s are fun, there\'s no doubting that! As fun as a kit car? not sure, more daily drivable though and very cheap to run :)
1984 Rx7: Gold. Edging towards roadworthyness!