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By Dan Macmillan (Kyote Registry) Date 2007-09-27 01:50
Does anyone have photos or plans to build a mid engine chassis for a buggy?
VW power prefered but Vair will be OK. I want to mid engine one of my Kyotes.
I have searched the net but cannot find anything.
Thanks
Dan MacMillan member of the DBA team. Author of the Kyote website, www.geocities.com/Baja/Desert/7445
By Bob E #19 Date 2007-09-27 17:10
Hi Dan,

I have some information posted on the mid-engined Deserter GS and there's a linked chassis drawing on this page you can pull down.  Go to http://www.deserterownersgroup.org/theGSpage.html to see more.

I also have a spare chassis that we've used as a template for a couple new variations.  It seems to have worked for me, but it's work building a chassis and all.

Have a look and let me know if I can help at all.

Boston Bob E
www.bimelliott.com
www.deserterownersgroup.org
www.the-bug-club.com
Boston Bob E
www.bimelliott.com - www.the-bug-club.com - www.deserterownersgroup.org
By Jeff GS Date 2007-09-27 18:11
Hi Dan,

In addition to what Bob stated, a couple of considerations:
The GS was 85" wheelbase (very close to the standard Deserter VW pan car at 84")
The GS uses a slight "cab forward" layout - it locates the cockpit about 4" more forward than the VW based car.  I'm pretty sure this was done to provide more room for the Corvair 6 engine - but it's still pretty tight even with a VW engine out back!
I think a mid-engine layout would work best with a transverse engine set-up, particularly with an inline 4-cylinder.  The longitudinal layout take a lot of length to make it work - and lots of neat and powerful FWD drivetrains to pick from, with modern 5-speed trannys, built in EFI, etc.  Makes a lot of sense to go in that direction.
I think Dave Barrett is working on a mid engine buggy chassis for one of his Manx's.  You might look him up for ideas?
The GS chassis is a marvel of simplicity and really a nice lightweight design.  No frills, but trying to substitute anything than the intended VW or Corvair power and swingaxle tranny and you really need to give it some thought!
Jeff
By Dan Macmillan (Kyote Registry) Date 2007-10-07 12:28
I have decided for now to just modify my Type 1 swing axle chassis to run the stock 1600. I did some measuring and immediately noticed that to keep the axles in the correct location I would have to cut a section out of the rear torsion housing.  Do I have to remove the torsion bars completely and install a coil spring type of suspension or are the bars short enough to allow me to cut out the center and have the engine to sit between them.
Any info is appreciated.
By Jeff GS Date 2007-10-07 13:13 Edited 2007-10-07 13:20
Hey Dan,

In my mind - it would seem to me that to "mid-engine" a standard VW chassis you'd have to pretty much back-half the chassis.  Engine would need to go where the transaxle normally sits, with the trans now hanging out back where the engine was.

Pretty easy to flip the ring gear around on a swingaxle for running midengine.  Unfortunately, that would probably be the easiest part of the swap.  I think you'd need to build a new frame starting somewhere around the rear torsion, and get rid of the original frame horns and everything rearward of and including the middle of the torsion assembly.  As far as I know, the OEM torsion bars extend pretty close to the center of the torsion housing, and connect near the center splines.  Cutting the center portion of the torsion away and you loose the splined anchor.  You might be able to substitute some mono-ball joints in place of the spring plates - but will definitely need to incoporate coil-over shocks into the new rear subframe  Look at mid-engine sand buggy designs for some ideas.
FWIW, the Deserter GS design required flipping the axle housings side to side, to locate the lower shock mounting point forward of the axle.  This was for alignment with the upper shock mount on the GS frame.  A simple triangular "trailing arm" locates the axle front to rear and takes care of axle twist, with a single hyme joint connection at the frame just off the roll bar.  It is a simple appearing design - but the height placement of the trailing arm mount at the frame was critical for proper suspension geometry.  That height position was also determined by the height and placement of the transaxle and inner axle pivot, all things that need to be incoporated into the design.

The GS frame can be used as a reference for your project.  Since it used the same mounting plane for the body as a standard VW pan car, that plane can be referenced for transaxle and trailing arm pivot height placements.  Took a bunch of measurements on my original GS chassis, let me know if you need any.

Here's a pic of my original GS chassis - before it went on the operating table:



Jeff
By Dan Macmillan (Kyote Registry) Date 2007-10-07 16:19
Thanks Jeff
I was afraid that the bars would be too close at the center. I was thinking to retain the spring plates by cutting the housing and bars and letting the bars free float. Then adding something along the lines of coil overs to replace the torsion bars.
I have searched everywhere and realized that not many people post useable photos of a mid engine chassis. I have only managed to find 2 that show, with some clarity, the way things are arranged. That pic you posted is a great help. I have never seen a pic that so clearly states what I will have to do. If you have any more pics I would greatly appreciate seeing them. Also any dimensions or sketches would be great.
Ever since I first saw the Deserter GT body style with the mid engine setup I have always wanted one. Due to the fact that I have been unable to locate one that is within my buget and have a spare 68 Kyote, I decided to combine the 2 and make a mid engine Kyote.

Thanks
Dan
By Jeff GS Date 2007-10-08 21:54
Here's some more info to take a gander at Dan - Mike Rag's awesome one of a kind Deserter GS.
Mike built his own chassis, loosely based on on an original GS chassis - but with many upgrades and some modifications.  Lots to browse through in his albums:
http://mikeragonese.shutterfly.com/action/

Also, you should google some kit car Porsche Spyder pics - I know there's one that keeps the VW torsion bars for rear springing, though the frame is custom - the Beck I believe?  Anbother called Vintage uses a coil-over style rear suspension.  I prefer the coil-over set-up myself.

I'll dig out my notes and see what I have that could be useful to you - as far as dimensions and transaxle placement relative to the bottom of the body.  Everything really hinges off the placement of the transaxle in the chassis - since the inner axle location from the trans becomes a fixed point.

If you wanted to keep the outer potion of the original torsion - I'd consider making up some kind of mounting plates that replace the outer torsion bar covers and bushings - with a large hole in the middle for attaching a big Hyme joint.  There's an outfit that makes a bolt-on kit for this - I think called Eagle?? or similar.  Can't find my link to the site at the moment.  You "might" be able to keep the upper shock mount portion of the torsiona nd add in extra braching and tubing to properly support it?

Jeff
By Jeff GS Date 2007-10-08 22:19
Another page to check out Dan - some bare (replica) Porsche Spyder frames:
http://www.pbase.com/carpediem/spyder_frames&gcmd=add_comment

Other than the Deserter - the Spyder has the closest layout to a fiberglass buggy as you'll find.

Jeff
By Jeff GS Date 2007-10-08 23:57
Ahhh... here's that coil-over conversion part I was talking about earlier:
http://00009q3.previewcoxhosting.com/CoilOverKits.html

Do away with the surrogate "spring plate" mount and utilize your own trailing arms.

If you look carefully at the Spyder chassis pics you may pick-out the torsion bar sticking out on that Beck.  Note how high it is above the bottom of the chassis - that's important on a mid-engine set-up.  Again - it's relative to the final placement of the transaxle - but I believe basically it must lie in-line with the axle centerline at the transaxle.  I'll check those notes I took on my GS and let you know.

Jeff
By Jeff GS Date 2007-10-10 11:30
Hey Dan,

I noticed there's a Vintage Spyder on ebay right now - some pics of the engine compartment and suspension.
# 230179450973

A similar subframe attached to the back of your VW chassis might be just the ticket.

Jeff
By Dan Macmillan (Kyote Registry) Date 2007-10-11 01:03
Thanks very much for the info and links. They have been of great help.
Please keep the information coming. You can never have enough.
Does anyone have a link to a place that sells Heim joints in Canada?
By Mel Adjusted Date 2007-11-14 18:31
I have a couple of Subaru mid-engine sand rails and thinking of building a biggy with a mid-engine setup. I use the Subaru 5 speed transmission ala Saker car's setup. Bremar Automotive who did Saker's engineering have helped me in converting the 4X4 5 speed transmission to a mid-engine setup. Works like a champ. In the past i've had problems with the VW flipped ring gear transmissions and couldn't afford a Mendiola (sp). I wanted to keep it simple and use stock parts.
At my age.. Everything I buy comes with a lifetime guarantee..
http://mel-adjusted.zoints.com/
By Jeff GS Date 2007-11-15 23:47
Hey Lilgeico,
Did you have any trouble getting the Saker/Bremar conversion kit?

I tell you, that's the way I was heavily considering going on my Deserter GS conversion.  The deal braker was - since the chassis was originally designed with a mid-engine VW swingaxle set-up - I found the WRX tranny wasn't long enough to get the axles in sufficient alignment (far enough back) without fouling the big DOHC heads against the framework.  Otherwise, if I was starting from scratch (on a mid-engine car) there's no way I'd consider keeping the VW or Porsche transaxle and adapting it to the Suby engine.  Especially considering you can get the whole 5-speed transaxle for the cost of the adapter kit, or less!

The WRX transaxle positions the axles a good bit closer to the engine/bellhousing surface than the VW or Porsche transaxles.  This would normally work for you to provide more cockpit room in the car - positioning the engine further back.

In hindsight, I should have done this anyway - as I wound up pretty much back-halfing the original GS chassis to correct later issues which at the time were unforseen.  I kept it somewhat similar to the original layout, but could have just as easily designed it around the Subaru drivetrain.  In that vein - it makes sense to utilize the whole drivetrain: axles, outer hubs, uprights, brakes etc. and adapt them to the package.  I wound up with a real mis-mash of different components, which while I believe will work great, though anything but easy to go down that road!

Hindsight is a much clearer view than looking upstream!
Jeff

Jeff
By Mel Adjusted Date 2007-11-16 09:41
I wasn't hard getting the kit after I contacted the right person at Bremar. My biggest problem was doing the electrical. Everyone put the fear of God in me about the Subaru wiring and it turned out easier than I was expecting. Also the myths about the EG20H TT engines needing to be converted to a single turbo is BS. I did some homework on the turbo's used on these engines and there designed for engines with 1,200cc's times 2 is 2,400cc's. I got rid of all the Sequencial TT crap and hooked them up as 1 turbo. Being there small turbo's they spool up really fast and I've been running them at 15# boost. I can get more out of them but I need to do some injector and ECU tuning before I go there. Im really excited about building a mid-engine buggy for the street with one of these setups. I think if I can keep the buggy's weight around 1,500lbs. with a 300 HP engine i'll have a power to weight ratio of 5:1 and will smoke Vetts an Vipers. With the right suspension might even out handle them.
Where could I post a dream I have for dreamers to do some dreaming?
At my age.. Everything I buy comes with a lifetime guarantee..
http://mel-adjusted.zoints.com/
By Jeff GS Date 2007-11-17 01:34 Edited 2007-11-17 01:39
This might be what you're thinking about??

My original GS chassis (in the pic above) has been undergoing metamorphasis:  Front end getting an A-arm rack and pinion set-up, rear a 5-link vintage formula car type suspension.  Huge brakes with Wilwood calipers.  My vision of the "100 mph buggy", as Manx Maniac used to call it back on the old DBA forum.  You could say his mental description inspired me!  Note the frame is still undergoing work in the pic - but you can get the idea.
It'll look mostly stock outside (that is a stock fiberglass body buggy), with the exception of a radiator showing in the front and probably an intercooler opening in the back/engine cover, with some new cooling vents grafted into the side pods (not too unlike the new Manxter).  It helps the Deserter has an 85" wheelbase - a little extra room to fit everything in!

Jeff

By Mel Adjusted Date 2007-11-17 05:36 Edited 2007-11-17 06:14
Dan, I seen a German forum where the guys were using autocad to design a mid-engine buggy. I can't read German so didn't save it to my favorites. I'm sure there's plenty of guys here with the know how to come up with something you need.
Jeff has the right idea but i'm not sure about the "100 mph buggy" part, unless me ment in 2nd gear. I'm thinking more on the  lines of a mid engine Saker buggy only lighter and with more power. Like a modern Buggy but with the same lines as the old one.

Dan, Here's some shots of a mid-engine mount...  http://homepage.mac.com/petecallaway/DeserterGS/PhotoAlbum73.html

For heim's here's were I get mine:  http://www.aurorabearing.com/
At my age.. Everything I buy comes with a lifetime guarantee..
http://mel-adjusted.zoints.com/
By Jeff GS Date 2007-11-18 14:29 Edited 2007-11-18 18:11
Lilgeico,

Please feel free to post your own pics here in the DBA forum - or share ideas!
I'd be very interested in seeing some pics of your sand car builds and hearing the details on how you incoporated the shift linkage, axles/hubs, exhaust, cooling, etc.  You may want to start a new thread on this in the Sub Bug (Subaru engine) section of the DBA forum?

I like the Saker too, though feel that an (80") fiberglass buggy may not have the "real estate" available to really use a mid-engine layout, especially if you want to use anything other than the VW beam front suspension.  I've literally spent years analyzing suspension geometry, parts manufacturers and countless designs to be able to "barely" fit these components into my GS.  It hasn't been easy!  And that's with the Deserter GS 85" wheelbase - 5" longer than most Manx based cars.  Utilizing the Subaru "package" drivetrain would provide a few more inches to work with in the shorter wheelbase - so that seems like a step in the right direction.

Using a full length buggy body would make the process much easier, maybe even the new Manxter?  Those extra inches in wheelbase will give you a bunch more options for little things like a place to put your feet!  That said, I'm sure with enough determination just about any buggy could be built mid-engine - just be prepared to make some compromises.  Also, Bob E (who posted early in this thread) has available a re-production engine cover designed for the Manx-style Deserter cars.  I believe this would be a good component to allow finishing the look of the mid-engine layout.  You might have to modify it a little, but may beat totally starting from scratch?

I too wanted essentially a mini Can Am car chassis under my Deserter bodywork.  As Autodynamics (who built the mid-engine Deserter kits) also sold and built more exotic race cars like Lolas, Formula Fords and formula Super Vees, I thought:  "what if they had further developed the GS and designed a chassis around these higher performance suspension designs"?  That was my driver to perform the "evolution" myself.  A mid-engine buggy with a real sports racer chassis and suspension!  The Bugetta is another buggy with advanced suspension design, but with a rear engine layout.  In hindsight (again), my current thinking is going back to the swingaxle arrangement but updating to ZRS configuration is the most straightforward and "proven" way to provide the mid-layout drivetrain for the least amount of $$$ and complication.  In the end, the main goal is to keep the tires flat on the ground during chassis roll (cornering), the ZRS does this beautifully.

I feel the Deserter GT bodywork may offer some aerodynamic advantages over a Manx style body, but how often will we be driving over 70?  Only the occasional short "blast" through the gears I'm thinking.  I also plan to build a front air dam that will hopefully complement the GT styling while providing some front end downforce and airflow control under the car and through the radiator.  My goal is to build a car that "could" be run safely and controllably for extended periods above 100mph - given the opportunity on a race track or maybe a hillclimb.

Jeff
By Sandsurfer Date 2007-11-17 11:25
I know it's just a mock up but, where would you mount the arm to keep the axle from moving fore and aft, in the stock springplate location?  If that was the case, wouldn't that give you a considerable amount of toe change throughout the range of the axle travel?

Jerry...
Jerry....
By Mel Adjusted Date 2007-11-17 19:03 Edited 2007-11-17 20:40
Look at the heading "TRANSAXLE and TRAILING ARMS" it shows the trailing arms arms.
It also shows how to use plastic flex pipe to make a mock-up header setup

With a swing axle you would get toe, but less than a standard swing axle as the way the shock is mounted. I don't have this problem as I use a Subaru IRS transmission and have mounted it somewhat similar.
At my age.. Everything I buy comes with a lifetime guarantee..
http://mel-adjusted.zoints.com/
By Jeff GS Date 2007-11-17 21:31
Yea, that's Pete Calaway's GS chassis update to ZRS (inspired by his dad, Reeves).  In hindsight, I probably would have done the same set-up on my GS - had I known the details of this layout when I began.  Sure is a ton simpler and less $$$ than a full IRS type suspension!
The trailing arms are shown in another of the links from Pete's webpages.  I'm 99% sure the forward pivot location needs to be level with the axle centerline (in side view, chassis level) when at ride height, with axles level side to side.  This minimizes toe change.  Ideally, you'd adopt another Formula Vee innovation and use "leading" links instead of trailing links - which would terminate/pivot behind the transaxle - at exactly the same pivot axis distance as the swingaxles themselves.  This would give a true A-arm function for the swingaxle trans. and 0 toe changes.

But, in the FWIW dept., I rode in and and drove a super GS of my friend Mike.  He built with a conventional GS swingaxle layout, coil-over shocks on either side (not ZRS) and trailing arms as shown on Pete's pages.  That car handled as if on rails, with no hint of "rear steer" or other funkiness you might think would be present on the swingaxle trans.  He wasn't even running a Z-bar on the rear.  Ony drove it on the street though, and I suspect any handling "undesireable-ness" might show up in more extreme handling manouvers - like on a race track or autocross?  But on the street at anything approaching sane driving, it was great.

Jeff
By Mel Adjusted Date 2007-11-18 19:23 Edited 2007-11-19 04:00
Jeff, I'm in the process of moving (110 miles) and it's a really slow process, but when I get all my stuff.... Camera, Cars, computers (My laptop doesn't have any pics) here I'd be happy to post. In the meantime I have to settle on sleeping on the floor and wishing I'd have made better choices on what I packed, I'll just have to ruff it for now.
I'd like to add here years ago I use to be General Mgr. of Allied Industries, makers of the "Volksrod" till Volkswagon sued us and we quit making them. Snider Fiberglass or Snyder Industries in Lincoln, Neb might still have our molds. They got all our molds which included the Cheeta, '27 "T", Corvette, both Cobras and a bunch of others just to name a few.
At my age.. Everything I buy comes with a lifetime guarantee..
http://mel-adjusted.zoints.com/
By Jeff GS Date 2007-11-23 13:08
I thought the Volksrod series bodies were made by a UK buggy outfit?  Was there a US version?
Jeff
By Mel Adjusted Date 2007-11-24 21:11 Edited 2007-11-24 21:42
In DB's Buggy Gallery you have Allied Fiberglass. If you look at the add you'll see our name was Allied Industries International. That add came out after Volkswagon sued us and we quit using the name of "Volksrod". Sorry but we were the original "Volksrod".
Another fact is we started building bodys in 1955. Even before Beirning and EMPI.
At my age.. Everything I buy comes with a lifetime guarantee..
http://mel-adjusted.zoints.com/
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