63 replies to this topic

[fuzzy-hair-man]

Hi all, I have been hanging around here quite a bit whilst I have been doing my Micra (CG13DE) conversion so I thought it's about time I tell you about it.

A big thanks to L_Jones, Rid's and Dutch mini for their help so far! These builds were part of the reason I decided to do a CG13 conversion rather than the more common Suzuki and Starlet / Glanza conversions (here in Australia). Other reasons include I like NA, I want mini handling and don't want the engine to 'overpower' this so I think the CG13 is more compatible with the mini (my opinion only...)

Anyway here's Spot as she sits at the moment, a bit sad it's true with no front wheels and looking quite rough but generally pretty solid. Spot is a 1967 / 68 Mini Deluxe, for you guys in the UK the Deluxe was an Aussie only spec with a 998 engine, wind up windows, hydrolastic suspension and drum brakes. Oh and our subframes are all solid mounted right up until Australian production ended in 78.

Here's some photos of the early stages of making the subframe, I remember sitting looking at the frame for a couple of days before attacking it with an angle grinder , I tried to stitch the sides in to restore some of the strength to the suspension towers. As you will see strength has been a major goal for making the subframe, I kept thinking if I hit a bump in the road at 100km/hr with the sumpguard (did this in my 78 clubman) or rails what force is the frame going to have to take? then I made it a bit stronger... The other criteria was I wanted to keep as close to standard ride height as possible as a lot of Aussie roads aren't very good and I hate driving along worrying about my sump.


These rails formed the basis for the frame to work from but running them under the sump meant I lost too much ground clearance so I decided to go in between the sump and the gearbox, but that has made the exhaust harder... oh well


A bit more:

by the way don't do you subframe jig like this, I realize it pushed me into designing it a certain way, pick up the front subframe mounts without the bar across the front.
Engine mounts:

Sorry no pictures of the back one it's much like any other conversions...

Finally we ended up with something like the frame we have now (actually there was a heap of work that went into it after this but none of it looks that impressive)


One of the big problems was we needed more room around the water pump and this required moving the engine forward which pushed the sump into the front bar... so we had to create some room. Sounds dodgy but it ended up quite neat and I have no reservations about it's strength. The Chalk line is where we eventually cut to then boxed it back up.


Actually pretty proud of the finished frame, a big thanks to my little brother who did the welding and my Dad, I peppered them both with questions and queries so I got it near right.
With the engine in the frame the whole package looks very compact and neat, there's no way I'm going to get the engine out without the subframe coming out though!!!

The rear of the subframe has been extensively reinforced with plate steel and is MUCH stronger!
Here's a diagram on how they were strengthened:


The frame has been shown to my engineer (all major modifications in Australia need to be done in consultation with an automotive engineer who then signs off that it passes the relevant ADR Aust. Design Rules). The process isn't quite as painful as it sounds, and keeps the standard of conversions generally high and safe.

Things / specs / intentions to come:

• Cooper S disks
• 10 inch Mambas (not sure what fits group 2 arches 5 x 10s or 6 x 10s I'd prefer 5 x 10's but have some doubts they will fill the arches)
• YELLOW!
• Grp 2 arches
• Possibly GA15 throttlebody and injectors (later on)
• Apexi piggyback ecu (later on)
• MR2 seats
• Maybe CD17 final drive and crown wheel to bring the revs down a bit. (I have a spreadsheet I could post but I'm not sure how to put it up so others can use it)
• A 5efhe / Micra hybrid inlet manifold (currently being welded up, a bit of a pain and $$)
• Hurricane extractors (designed for a micra for $50 2nd hand!) to be modded because I used some of the space between the sump and gearbox.
• 2 degrees negative camber bottom arms.
• Adjustable tierods / castor bars.

I'm actually tempted to register Spot in her current form as a bit of a rat rod mini have some fun and then get it stripped and put back together properly.
Here's a photoshop of what I hope the finished mini might look like...


Anyway I think that's all for now, I only get to see my mini occasionally so please forgive me if progress is slow.

Ask any questions you like I'll try to be helpful...

[l_jonez]

Looking good! It's about time you put your build up

Sadly where I live off a stone track I cant go to low with the mini but it does mean I got decent ground clearance ( a inch less than standard)

Are you putting any box section between the front bar and the towers? I got mine going from the top of the towers and others have it lower to create more of a cradle
(Borrowed rids pic)



Good work tho, it will be interesting to see your finished manifold as I'm still tempted to do mine

[fuzzy-hair-man]

I asked the engineer what he though about putting some bar along the outside as you suggest his opinion was that it wasn't required.
The rails are 40mm square tube with I think a 3 or 4 mm thickness so they are pretty strong, it's one thing that worries me a bit is the weight of the subframe...

The 40mm size of these rails means that I would have lost more clearance than you so I decided to go round the sump instead. I think my clearance is about the same approx 1" below standard but higher than standard with a sump guard.

[rids]

3rd year coming up and although my subframes not pretty, ive had no problems with it. (and its been driven hard). I didnt go from top of towers to front as i wanted to keep inner wings intact, I have rails going just under sump and it was always my intention to fit a sump guard to these. however i havnt yet. ground clearance looks worse than it actually is. Because the lowest point of subframe is close to being in line with wheels, it rides over bumps with no problems.
I think i'm going to do another conversion with my sons mini and will probably do the subframe very similar to mine, however, his car has no inner wings and I would probably try and get alternator to the front (similar to mr jones's) also carb and megajolt to simplify wiring.
your photoshop'd picture looks very nice. keep up the good work, It'll be worth it.
as for the handling and mini feel, I'm sure others will agree, the handling isn't compromised and the mini feel is still there, I think mine has the power of a well sorted 1380 but with reliability. and is a fast, fun car that can be used daily. and about 40mpg as well

Edited by rids, 24 April 2013 - 06:52 PM.

[l_jonez]

yep handling is spot on, theres no noticeable difference from standard.

a recent 190 mile round trip i got 42mpg and i wasnt hanging around constant 60-70mph

Edited by l_jonez, 24 April 2013 - 07:07 PM.

[rids]

did it take much to get your carbs jetted right?

[l_jonez]

Not really, I've got a wideband o2 sensor so I've done it myself, just monitored the afr and went/down a jet size as needed.

[fuzzy-hair-man]

A couple more photos:

 

The MR2 seats sat in the car (thinking of mounting these using a second cross member):

 

They fit nicely I think I got 3 seats for about $AU110 and just had to transfer a passenger seat covering to the drivers to get a good pair   

 

The extractors I'm hoping to adapt as I used some of the gap for the frame:

 

Lastly a pic of the subframe in the car looking down the driveshaft hole:

 

[cal844]

looking good mate, if you think Aus roads are bad, you should come to scotland... we have 6 inch craters and speed humps(damn EU b@5turds

[Tomm]

Nice to see another Micra based build! Will keep my eye on this.

[domdee]

these micra builds are very thempting

[fuzzy-hair-man]

A bit of an update:

 

The guy I was getting to graft the Micra and 4EFTE manifolds together gave up on it(could have made it but the outside runners were going to be less than ideal and flow worse than the inner runners) and we ended up going for a custom manifold, it ended up costing a fair bit more than expected though.

Interesting design huh? it wasn't what I was thinking of but nice and with little air horns inside.

Anyway a photo:

 

With the radiator in doesn't look like much room for a air hose but I think I might be able to get a 135 degree silicone bend on it.

 

Had to re-think the alternator mount, I was placing with a different idea, the alternator adjustment would come from the front of the engine...

 

Only problem is my bracket hits the fuel rail  easily solvable just got to play around with it some more.

Edited by fuzzy-hair-man, 12 September 2013 - 02:02 PM.

[l_jonez]

Nice to see some progress :) manifold looks diffrent but should work nicely

[fuzzy-hair-man]

Apologies about the glacial pace of my build but I've had a bit of progress lately (I have a motorhome conversion that's taking priority)

 

Anyway the subframe got in the way of the extractors so it got modified (It just gets rid of useless metal so the frame is better anyway):

The modified frame, 40mm square tube now goes straight up to the sides of the engine mounts which allows more room for the extractors.

From this:  to this:

 

 

Next up I had to modify the micra extractors to suit (one of the pipes runs where part of my frame is) I've trimmed them back about 2.5cm to bring the pipes back towards the block and have to reroute some of the pipes. if we got anything except a Lotus with the rover K series engine these might have been an easier option.

  and 

 

Tacked up and sitting up next to the block (getting them welded up properly on Monday along with some pipes bent to go under the sump):

 

Hopefully soon get the alternator mounted and modify the clutch.... nice to finally get something done on the mini.

[l_jonez]

Good to see your still at it :)