Nocones Rotary MG Midget

I fixed it!  

I took the front clip off and did some inspection.  

Basically ripped the front belcrank mount off.  Failure appears to be due to base metal failure.  Welds held for the most part.  Looking at the parts it turns out I made the mount out of .065 (16 ga) which is common locost frame material.  I think the overload of the curb was just to much.  It doesn't look like it was fatigue over time.  

The rest of the frame was fine other then this lower frame extension for the fender mount.  I just cut it off for now so I could get the car back together for an autox.  

To ensure it doesn't happen again I added a piece of 1"*1/8" strap vertically along the part and extended it down to the tubes underneath.  I will likely do some more reinforcement over winter. 

Autox this weekend went ok.  It was 40* and I ran A7s.  The tires never got heat so it was slow but still entertaining.  Ended up 3rd on raw behind a very very fast STR ND Miata.

Winter plans are just some light maintenance and focus on the new Subaru project.  Though the more I look at the GC8 I bought for a donor the more LeMons/Chump calls to it/me..   may need another donor..

So after all this seat time, how are you feeling about the pushrod actuated motorcycle coilovers? Anything you would do differently? 

I have been dreaming of doing exactly that and have been hoarding a selection of shocks for at least a decade. 

In reply to Jumper K Balls (Trent) :

I like them.  It was critical to remove the preload as that made the car drive better.  I would and will use them again.  I have messed with the adjustments and have found that they seem to have reasonable ability to change the way the car feels.  

I need to try to run the suspension overall softer as it's quite stiff but for track days it has been great. Performance stays consistent over 20 min track sessions so it doesn't seem like they have any issues with the weight of the car.  I'm sure big money shocks would be ever so slightly faster but I do not feel that they limit the performance at all.  

I would attempt to use them on any car that weighs less then 2200lbs.   The compromise of travel vs spring rate is real at ~700lb/in and 2.2" travel you really are limited on your possible corner weight/wheel travels but they seem great for my car at 1800lbs with driver.

nocones said:

I had a friend codrive this event as I want to share the car with people and I need it to get more runs on it to get the kinks ironed out.
I got all 6 runs however my co-driver only got 3 but not because the car broke but because the car broke him. He found a burr on the drivers door and it cut his hand He unfortunately couldn't finish the event. He did enjoy his 3 runs and the seat is open.

I think I may have been the first one to co-drive this car with nocones. I still have the scar on my hand. I have quite a few scars but I think the one on my hand is my favorite. It definitely has the best story to tell.

I got to drive the car again at the AutoX this past weekend. It is such a riot. I was pretty timid driving it at first. I haven't raced 'fast' cars. Focus, NA Miata, RX-8. All fun cars but fun in the 'slow car fast' way. To me, this car is properly fast!

My legs are pretty long and I had some trouble trying to find a seating position that my knee didn't interfere with the steering wheel. I ended up clobbering a cone because my hand hit my knee, limiting steering input. It was enough to crack the upper front fender mount so we pulled the fenders off. It was kind of cool being able to see the wheels move and watch the suspension work. I finally felt comfortable driving it on my final run and managed to get to 13th raw time- I am a pretty crappy driver but was happy to finally be comfortable enough to start pushing the car a little bit.

The pictures don't do this car justice. Nocones did an awesome job building this thing and I really appreciate his generosity sharing its awesomeness with a hack like me. It has been a blast getting to help during some of the build and getting to drive this car. 

In reply to nocones :

Gracias sir. Glad to hear positive feedback from someone with actual experience 

May I inquire as to which units you are using? I think I have a few gsx-r750, some cbr and aprilia rsv4 I'm hoping to use

I'm using CBR 600 F4i shocks on the front (800-900lb/in) and R1 on the rear (600 lb/in).  Travel on both is 2.1-2.3 in.  The R1 shocks have different spring rates depending on model.  If you want to push the weight limit the Hyabusa shock apparently is like 1300lb/in and has 3" of travel.  

I haven't forgotten about you MG.  It's just with pandemic I haven't played cars much this year.  But that changes this weekend. I decided to register for the Gridlife Event at Road America.  It's on my list of tracks I want to run and I'm tired of not doing car stuff.

So that means car preps.  The MG has never had a proper tow hook.  The front is very troublesome as the radiator is wider then the frame.  I tube origimied some uprights and a cross beam.  I had to remove some metal from the front grill but I now have a 1/2" tow anchor.  I'll fabricobble some tow hooks out of rebar for now and maybe will make something more "Racecar" later. 

I was not interested in pulling the rear bodywork so the rear hook clamps to the chassis with what seems to be 11lbs of plate.  I will eventually change this but for now function over lightness.  

The impact at Putnam also took out the front fender mounts.  The tow hook adapter offered a great anchor for the fenders so some old bed frame angle iron got turned into mounts.  

With all the fab done it's time for reassembly, coolant flush, a good nut/bolt and inspection of the suspension.  I will also likely change the oil, flush the brake fluid and may clean the rocks out of the car.  

I'm also going to shoot some pictures and video of the car as I really have never posted anything of it "finished" so expect some stuff on that soon.

Now with paint and hooks.

I look forward to a write up on the GridLife RA experience... and the 'culmination' video

Yes, great to see you are getting out there this year. Good luck and looking forward to the video as well!

My Brief thoughts are:

It was an exhilirating weekend.  I was very intimidated by car track combo, and my trepedation wasn't made better by the fact that it was soaking wet for 4 of the Saturday sessions.  

The Short summary is the Track is Amazing, The car ran flawlessly during all 10 sessions, I got ~3.5 hours of on track time.  

The Gridlife event was great,  everyone was friendly and inclusive, and adherence to COVID protocols was good and felt safe and considerate.  

Reaction to the car was great, and Gridlife did a photo shoot and Video shoot of the car so I'm not sure when/if we will see the results of that but I will share when I see them.

I am definitely planning on running additional events with Gridlife.  

I will have a more complete writeup in a few days.  I hope to have the video put together this weekend but for now a brief teaser:

In reply to nocones :

It was good to get to meet you in grid! Love the car, was fun watching it come around every time.

In reply to spacecadet (Forum Supporter) :

I'm glad you guys got to meet up there. Now we just need to talk nocones into bringing the MG down to the Nola event!

I posted in the wrong place I think, so a redo, but anyway Just kind of a been there-done that from an old guy.  I built a rotary Midget back in the dark ages when the donor cars were a RX2/RX4/RX5.  Predates most anything to do with CAD, or email, or internet.  Kind of went from stock 13B street car to supercharged 400+ not a street car.  Certainly a lot of fun as long as there was concrete, pretty worthless on asphalt.  A sharp eye might recognize Tim Suddard  working the course at Salina, camera in hand, about 30 years younger.  I sold the car several years back to go road racing, which my son and I do now.  We still autox too, but it has just never been the same after running modified classes.  We will be back in EM this next year with a re-engined EM Miata with a LS replacing the gone now 20B.  So, I may run into you at an event somewhere.  The rotaries have not been abandoned, as the SCCA car is a RX7, and the vintage car a RX2.

In reply to hobbyshophotrods :

you should post more. i bet you've got stories to tell!

In reply to hobbyshophotrods :

Sounds like your old car was pretty cool.  I know that people have been putting rotaries in British cars for years.  I had seen a few prior to building this one.   You should put up some details on the LS EM Miata.  That will be an interesting EM car.  I've not been Autocrossing much for the last few years.  This car isn't really optimized for autox (To heavy, not enough power, not running 14" wide 13" diameter slicks, etc.), and I've been enjoying the more seat time you get with HPDE events.  I'm slowly working my way up the NASA ladder to eventually get to Time Trial and W2W.  

New Video is up on Youtube. 

Walkaround of the car with a few quick videos of the car on track.   Plus Video of the time is stuffed it into the hay bales at Putnam Park.

I will probably make videos for the MG anytime I do any major work or at future events.  It's becoming apparent that I need to work on getting a microphone.  The audio quality leaves a lot to be desired.  That's next on my list.

good stuff on the video.

in watching that, I noticed some surface rust on your pushrods.  Are those steel?
I never had the contact info, but on the Aircraft Simulators I used to work on, we always used an anodized aluminum octagonal bar for our control-linkage pushrods.  It was real important to minimize weight in that mechanical system, so the backdrive motors had less inertia to deal with when modeling the aircraft's control forces.  Seems like your suspensions setup would be a similar design landscape?

In reply to sleepyhead the buffalo :

Yes they are steel.  I had always intended to replace them with aluminum.  You can tell by the fact that I have never fully welded the links.  

Weight of unsprung components should be minimized.  It would be interesting to see if there is any noticable difference if they were changed.  Aluminum is ~.5lb/ft and the steel is 1.1lb/ft.  Each part is around 15" long so it's a difference for each of about ~3/4 lb.  Compared to the weights of the remaining unsprung components (Uprights/brakes/wheels/tires) they probably represent around 2%.   I'd guess on your aircraft simulators the linkage could easily represent a huge proportion of the controlled mass.  

nocones said:

In reply to sleepyhead the buffalo :

 I'd guess on your aircraft simulators the linkage could easily represent a huge proportion of the controlled mass.  

It could be... it depended on the simulator, the control axis, etc.  One other thing is the tightness of the tolerances, and the types of tests we had to perform.  Which usually included a "semi-static control forces sweep", and a "dynamic release, damping" test... and that last one was a particular bugger to pass if you had too much system mass... because you had no where to add 'virtual damping' in via the code.

Hmm.  Long time no update.   I've been doing some thinking.   I really want to streamline my automotive mayham some.  I have to much stuff and to much of it sits around doing nothing.  

So now that the LMP360 is "done" and has shown that it is competent on track the MG becomes somewhat unnecessary.  In fact I only drove it 3 times this year, once before the Gridlife event to make sure it worked, at the Gridlife event, and to a Cars and Coffee.  The 360 by virtue of it's cage design is simply the better choice for a track car, and the two cars are very equal at Autox with neither being particularly competitive in class.  The MG has a big advantage though.   It wears a plate.  

The MG is street legal, but I don't drive it much.   The reasons I don't drive it a lot are:

1. It doesn't have turn signals.  Those are kinda necessary. 

2. It's kinda uncomfortable.  The seats are very upright, on track I can handle 20 minutes in the car but that's about it.  On street because you aren't moving around as much I get pretty bad cramps in my hips because the seating position is basically 90* upright.  

So what do I do?   I could sell it and buy something more streetable.   But that opens up my Liability concern can of worms, and I put a lot of effort into the car so keeping it and enjoying it makes more sense.  

So I'm leaning towards modifying it.  

I can't recline the seats any further because the harness bar and diagonal are right there.  I could move the driver's seat back using a bent harness bar, but then my head would be inline with the rollbar which is bad.  

Here are a few pictures because pictures are best.

The chassis is built to be 1 piece with the rollbar.  This is an excellent design for a car that will never change, but redoing a full floor to top regulation rollbar basically will require cutting the car in half.   That's work I could do.  But I'm not sure the car has to maintain a fully "Legal" cage.  The most it will ever do is HPDE which for convertibles just requires a 4pt bar.  

So I am leaning toward cutting the bar off.  Here are some pictures showing what I am thinking of doing.  

I would cut the main hoop at the top of the rear horizontal.  I would redo the upper side impact bar lower to this new node.   I don't plan to restore useage if the doors so the current layout is fine but I may investigate bent bars to make a more functional door opening.  

A gusseted pad would be made behind the old vertical roll bar with a new tube down to the floor that would take any vertical loads.   A permanent harness bar would be installed at this pad to tie everything together.  

Then a lower (possibly bolt in) 4pt bar with diagonal would be added.   I probably will be able to reuse the cut out existing hoop, unless it's to wide for the rear parcel shelf.  This would be about 6" back and 6-8" lower then the existing.  This should allow reclined seats to be used improving comfort of the car immensely, while still giving head clearance.  Probably something more like lotus Elise seats then the Kirkeys, but I may make my own carbon Fiber ones because I've wanted to do that for a while.  

I believe this would still be accepted by most HPDE if I ever ended up driving the car on track again.   And If I ever decided to use it seriously again I would cut the chassis appart and fix it with a modified main hoop that goes to the floor.   

So I'm not sure when I will get to it, but I may be Sawzalling the MG soon.  It would be great to be able to drive it more and that's more important that maintaining 2 legal caged race cars.    The rest of what it needs is pretty easy stuff.  Maybe I would paint it also..   .  

I will keep this updated as I go but just wanted to chat about what was going on.  

As soon as you described the situation, my thoughts were "less roll bar" and it seems you are on the same page.

How enjoyable is it otherwise? You have a pretty broad choice of cars to choose from every time you leave the house, what keeps you from making this one your choice every time? Noise, Vibration, time to warm up, fear of roadside breakdown, heat in cockpit, overheating, sore butt? 

When DO you make it your choice? For most of us, this would be a "me" only car with the wife crossing the street to avoid the drive; this takes a huge swath of driving time off the table right up front and can not be fixed.

I sold my MGB GT after 40 years of ownership because I admitted that it was at the end of its development. It was baggage that was holding me back and not really serving any function other than stationary art and feeding Hagerty.  I have restarted the cycle with the Molvo unencumbered by the baggage of the MGB.

In reply to NOHOME :

You've nailed the position I'm at and your spot on with your considerations.  

It's great otherwise.  The suspension is soft enough, It's not to hot inside, being a rotary there is no vibration.  M-F I drive a 24ish mile round trip commute that I could use it on solo so it would see mileage.   The thing stopping me is comfort, lack of turn signals, and the exhaust tends to come back into the cabin and since it runs premix this gets you coated lightly in oil soot.  I have never fixed those things becasue the roll bar design had made it impossible to fix the most important one - Comfort.  

I've enjoyed 5 years of using this as a pretty much dedicated track car.  I think it's time to put it under a bit of the knife again to make it a decent dual useage car..  

It's funny technically this is my First car, but also the one I have the LEAST amount of mileage in. 

In reply to nocones :

I'm glad you've decided to keep it. You've had it most of your life, it would be a shame to let it go, then lose track of it. 

So as you all know from the Subaru project I like to do Freeware CAD (Sketchup learning Blender) and Renderings (Twilight Render) to explore Ideas.   I have some ideas for the MG and want to be able to explore them.  However Shockingly I have never put the MG into Sketchup.  

So I rectified that this weekend during the F1 festivities.    They aren't perfect, but they will work. 

Overall I'm pleased with the results for freeware software.  I occasionally get weird reflections on the parts I generated (Fenders) compared to the same curvature on the parts from the existing models.  I also struggle with textures on things like the Tires but I'm getting there.  I know that Blender has better rendering and materials support for Non-architectural things then Sketchup so I'm planning to learn more competence in that.  Also Blender is a necessary step to get cars like the MG and LMP360 into Assetto Corsa.  I've ported the LMP360 in but I only have the Chassis and am struggling with understanding materials in Blender (And particularly the AC material painter) but that's for the future.

The first things I wanted to explore with the MG was the elephant in the room.. Paint.  It's controversial but I don't know that I want the car to be a "ratrod" forever.  IF I painted it, realistically I would flat clear what is there and wrap it so I could put it back so do not worry that the current finish would "disapear forever".

E36 M3 It looks.. really good 1 color.    

So since the Digital space is wonderful and you can do anything you want..  I pulled the LMP360 in and did a mini photoshoot.  

The 360 obviously needs some updating.  The model is behind reality at this time but it was too cool not to share.

Then things got out of hand as I pulled basically every car I've modeled in for a "Dream Garage".   4 of these cars will be built..    I can't afford the 5th one yet.  

I will start a build thread for Brumpy the 2023 $2000 challenge WRX soon.   The Panhard is not shown because I have to model it entirely from scratch.  Strangely I have not located a Sketchup model of an Obscure low volume French car..  That said I will model the Panhard in Blender which will require much learning first.  That's a good "way to cold in the garage" winter project.