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PostPosted: June 25, 2019, 2:03 pm 
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Hello all, after many years of finding myself perusing this forum, I finally found a reason to join the fun. Long story short, I got bored waiting on my 1974 BMW 2002 being complete enough that my good friend Matt, owner of Beaver Built (an awesome fabrication shop in New Jersey) could ship the car to me to complete. So, as I often do, I was on Craigslist and came across a 1963 Meyers Manx (replica).

Bah! I thought, I have no desire to buy a VW! (Sorry Bug fanatics).

But then it hit me- It was titled as a 1963 special construction, with up to date tags and plates. And it looked cool. I had no desire to build another offroad vehicle- but it would make one really fast street rod.

Fast forward two weeks and I have an almost completely deconstructed buggy sitting in my backyard, a bunch of DOM tubing on order, and the spindles and wishbones from a Saturn Sky / Pontiac Solstice ready to be delivered to my door. Within the first week the scope grew from "mid engined EJ25 with beetle IRS and make it work" to a proper double wishbone front and rear, using the J35A4 out of my girlfiends rusty Honda Odyssey that is just rotting away in my backyard. I'm planning on using a 901 Transaxle with a Kennedy Adapter, unless if someone has a more stout suggestion (that doesn't cost mendeola money). This will be my first road going custom chassis, but I was formerly a Formula SAE / Baja SAE member and I have a degree in Mechanical Engineering, so I know enough to know what kind of sh*t storm I have just created for myself. :mrgreen:

This build is meant to be cheap, fast, and a platform that I can easily adjust and tune. Some items are still up in the air:

CV axles... unless I can find a CV that has a flange on one side and fits the Saturn Spindle Spline(same as a cobalt I believe), I'll sleeve and weld a 901 CV to a Saturn CV.
Shocks... I'm leaning towards a cantilever or pushrod setup using motorcycle rear shocks, but I am still undecided.
Anti Roll Bars... Depending on my shock arrangement I may either use a standard ARB or a linked arrangement if I use a pushrod setup.
Steering Rack... Manual of course, will depend on my final track width so that I can find something the correct width to eliminate bump-steer.

The chassis will retain the original VW center tunnel, modified to mount the cable shifter and Hydraulic E-Brake. The torsion bar and front beam mounts will be used to help square up and locate tubing prior to being cut out. The tunnel will be deeply notched in the rear to lower the J35A4 as much as possible. Floor pan will be custom to meet up with the tube chassis sides that will tie the front and rear together. Ride height will most likely be determined by transaxle output flange height so that I can keep the CV's nice and even. Minimal anti squat/dive geometry, 10% or so with adjust-ability between 0 and 20%. Stock Saturn control arms at first, but I will make some custom adjustable units once the car is together. The wheel base will have to grow at least 6" to leave enough room in the cockpit for the driver. I'm obviously glancing over some details at the moment- there is only so much I can address in an introduction post.

Now, some pictures. I'm not afraid of rust, being a NYC native. :lol:

https://photos.app.goo.gl/27wycQq4BKXPLpJn9


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PostPosted: June 27, 2019, 9:44 pm 
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Might be a bit simpler and cheaper to leave the sideways engine and trans intact unless they are too wide?
Also would allow you to not lengthen the wheelbase so much?

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PostPosted: June 28, 2019, 1:40 pm 
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RichardSIA wrote:
Might be a bit simpler and cheaper to leave the sideways engine and trans intact unless they are too wide?
Also would allow you to not lengthen the wheelbase so much?


I initially was going to run a subaru EJ25 which is only slightly shorter than the Honda J35. Plenty of width for the Honda V6 or a Subaru Flat 4. The Original VW engine was in rough shape, I've since sold it as a core.

I'm okay with lengthening the wheelbase a few inches- it should improve stability.

I heard back from Kennedy and it turns out they have an adapter available to use the Honda J35 with a Subaru 5MT, so I will use that transaxle instead (With a locked center spool to only output through the front axles). I've been doing some sketching and have determined my ride height will be dictated by my front tire clearance to the fender. I considered a body lift to lower my ride height further but decided against it. I'm planning on a 205/40R17, the smallest diameter/width I am willing to accept, with 3-4" of up travel. Currently I'm still waiting on my donor parts to arrive to properly determine everything. I should use the time I have this weekend to remove the Honda motor.

Anyone in Socal want a crusty 04 Odyssey rolling chassis with a nice cloth interior? :ack:


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PostPosted: June 28, 2019, 1:48 pm 
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RichardSIA wrote:
Might be a bit simpler and cheaper to leave the sideways engine and trans intact unless they are too wide?
Also would allow you to not lengthen the wheelbase so much?



I've just realized you meant to leave the Honda V6 as a transverse mount instead of using it longitudinally. I considered it, but it would be a bit too much weight over the rear axle. Additionally it would make plumbing everything a bit of a hassle, and it won't look nearly as cool 8)


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PostPosted: July 1, 2019, 1:16 pm 
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A quick update. I was able to free the J35A4 from the Odyssey over the weekend with the help of a friend. Very involved as you have to drop the front subframe and remove the motor from the bottom of the van. Relatively uneventful, and I was able to keep all the OEM electrical connectors in perfect shape.

Had ~70ft of 1.5" 0.095 wall DOM and ~70ft of 1" 0.095 wall DOM delivered last Wednesday. I got really great pricing through my work account. I was also able to stop at a friend's place and borrow a ton of equipment- tubing bender, chop saw, and a rusty table or two to aid in assembly. It will take some time to unload and clean it all up, but it is a welcome addition. I will have to modify the tubing bender so that I can mount it to my truck's hitch as I don't want to put lag bolts down (I rent the property I am living/working at). Will have to make a second stop at my friends place to borrow one of their MIG welders. I have a TIG, and a ton of excellent fab tools and machinery, but it's all back at my parents place on the east coast. Luckily between what I have access to at work and what my fellow auto friends have laying around, I won't be without any tool I may need.

I'm still waiting for the spindles and wishbones to arrive, that is currently holding up my determination of suspension mounting points. I'm also still on the lookout for a Subaru 5MT transaxle, and need to order the Kennedy Adapter Plate.


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PostPosted: July 3, 2019, 1:58 pm 
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I now have 3/4 corners worth of control arms and spindles in my possession. I'm going to try and adapt the spindles to run cobalt (non-SS) hubs, which should be a bolt on affair. I'm also hoping the caliper brackets will bolt up, but I imagine I may need to machine some parts to run the cobalt calipers and smaller diameter rotors. This will allow me to go to 15" wheels with a 4x100 bolt pattern which are more appropriate for a car of this size and will allow me to reduce my ride height compared to the 18" Saturn wheels in the weird 5x110 bolt pattern. I will run the same rotors and calipers front and rear and will adjust bias using a tilton pedal assembly with bias bar/different MC's if needed. Ride height is being dictated by the relatively low front fender height on the manx body.

What software is everyone using to determine their suspension geometry? It seems a lot of the links in the running gear subforum are dead. VSusp is handy for visualization but leaves a lot to be desired. Since I will be reusing the Saturn control arms, my geometry is fairly fixed, but I think I should be able to get 2-3° of front camber and 1° of rear camber while keeping the roll center flat throughout +-5° of body roll based on a quick look at vsusp. Also minimal camber gain (+0.5-1° or so with each inch of bump). I'm planning on 4" of up travel. I'd like to avoid modeling it all in solidworks (I'd have to come into work to use the copy I have here, as I only have Siemens NX at home which I find to be frustrating with larger assemblies). I'm okay with spending a few hundred dollars on some good software (suspension analyzer comes to mind?), but freeware is always welcome.

I'm picking up a JDM WRX transaxle saturday, and have begun looking at CV axles. I'm really hoping I can re-spline the WRX axle to fit the chevy outer CV. I doubt a half shaft already exists to go between a WRX transaxle and a chevy cobalt :lol: . Kennedy has a 2-3 week lead time on their adapter.


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PostPosted: July 6, 2019, 11:42 pm 
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Scratch my last post... I won't be able to fit 15's over the stock UBJ and LBJ. :roll: 16's might clear but have terrible tire selection, so I've settled on 235/40r17, at least as a starting point. I've had a play around with VSusp and have been able to get a decent front and rear roll center, static camber setting, camber gain, and extremely flat roll center y position with body roll up to 4 degrees.

The LOLCost

Also today I picked up my subaru wrx transaxle. 4.44 final drive as the dismantle ran out of 4.11's, so acceleration is going to be... interesting. It appears to be a fairly well maintained JDM unit. I'm going to attempt to weld the center diff myself to save money buying one of the Bremar units. I included a quick sanity check picture of the spindle and control arm offered up to the front of the chassis. I might just be able to keep the majority of the fuel capacity of the stock front tank.

More work to be done tomorrow- I spent all of yesterday reinstalling the honda subframe and stripping the wiring harness from the dash.

https://drive.google.com/drive/folders/ ... sp=sharing


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PostPosted: July 7, 2019, 5:30 pm 
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Location: central Arkansas
Someone pointed me to these guys a few months ago:

https://www.3jdriveline.com/lsd/

They're in England. https://www.teamblitz.com/ is one of their US importers.

There's a pretty big WRX aftermarket; someone might make a spool.


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PostPosted: July 8, 2019, 5:57 am 
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Going to follow this one with interest! You are ripping into it, looks like a good combination of parts, should be a blast to drive.

Manual control of the J35 will be far better than the auto that the transverse setup would require.

What ECU are you using? I am experimenting with a J35Z2 and a DIY speeduino unit from Australia, like Megasquirt but open source using an arduino controller.

:cheers:

Marcus


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PostPosted: July 8, 2019, 12:22 pm 
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Kinetic Research wrote:
Going to follow this one with interest! You are ripping into it, looks like a good combination of parts, should be a blast to drive.

Manual control of the J35 will be far better than the auto that the transverse setup would require.

What ECU are you using? I am experimenting with a J35Z2 and a DIY speeduino unit from Australia, like Megasquirt but open source using an arduino controller.

:cheers:

Marcus


Ripping into it for sure! I battled the Odyssey dash all afternoon yesterday... What a royal PITA... Ended the day with the dash free and most of the loom disconnected, but I still have to clip some zip ties to free the dash harness.

I plan on using the stock Odyssey J35a4 ECU at first. The main issue people run into with that ecu is the auto transmission not being present. As best as I can tell, you can mostly get around this by sending the crank signal pulse to the transmission input shaft speed pin on the ecu. Also you need a way of telling the ecu you are in park to start the engine, and D to prevent the ecu from limiting redline and disabling vtec- fairly easy using some relays and the factory schematic.

I'm also using the odyssey gauge cluster, ignition key/immobilizer, and some other goodies.


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PostPosted: July 8, 2019, 12:31 pm 
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TRX wrote:
Someone pointed me to these guys a few months ago:

https://www.3jdriveline.com/lsd/

They're in England. https://www.teamblitz.com/ is one of their US importers.

There's a pretty big WRX aftermarket; someone might make a spool.


Thanks for the info! I'll take a look.


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PostPosted: July 8, 2019, 6:27 pm 
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You might want different offset for the rims due to the amount of scrub.
Consider balancing the camber gain in roll with the camber loss under hard braking (one wheel bump).

A shortened manx buggy doesnt have much room for an engine behind the driver without stretching the wb. A transverse bec with a hawk coupler to a small irs diff should fit pretty well though no reverse.

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PostPosted: July 8, 2019, 8:01 pm 
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Miatav8,MstrASE,A&P,F wrote:
You might want different offset for the rims due to the amount of scrub.
Consider balancing the camber gain in roll with the camber loss under hard braking (one wheel bump).

A shortened manx buggy doesnt have much room for an engine behind the driver without stretching the wb. A transverse bec with a hawk coupler to a small irs diff should fit pretty well though no reverse.



Interestingly, the wheel offset is the factory offset from the saturn sky/pontiac solstice. Stock they run 18X8 ET55. I did note the amount of scrub in the front wheels.


I'll take a look at the camber gain in roll vs camber loss under hard braking (just thinking about it, wouldn't increasing camber gain for one also increase it for the other? ie adjusting the top control arm to be at a steeper anger for increased camber gain?)

You're correct... the manx is very short. I will be stretching the wheelbase ~5-8" or so to accommodate the J35 and subaru transaxle. Worst case if I need to move the rear wheels back so far that they interfere with the bodywork I'll glass in new fenders. I'm too invested in the J35 and transaxle to switch plans now- adapter plate is already on order. I'm okay with being a bit cramped- I own a 71 Mini so i'll feel right at home :lol: .


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PostPosted: July 9, 2019, 10:26 am 
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Rocan, I can't add anything to this thread except that another builder, Langan, has done the stretch Manx. You might find something interesting in his build log.

viewtopic.php?t=15980

Build on :cheers:

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PostPosted: July 9, 2019, 12:01 pm 
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rx7locost wrote:
Rocan, I can't add anything to this thread except that another builder, Langan, has done the stretch Manx. You might find something interesting in his build log.

http://www.locostusa.com/forums/viewtopic.php?t=15980

Build on :cheers:


Thanks for the share! Definitely an inspirational thread. It does leave me slightly concerned about my engine fitment though. I planned to have my seat about 6" further forward than where Langan placed his. It should be fine considering his 6'8" son looks comfortable in the car- I'm nowhere near that tall :cheers:


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