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Im trying to figure out what transmission to buy for my kit. I have bought some haynes manuals for the beetles. I dont know if my chassis is going to be swing axle or IRS. One of the manuals states that the only “Double jointed drive shaft” (assuming this is IRS) model is semi automatic... i dont want an auto box. My basic question is, do all manual transmissions accept both axle types, double jointed (IRS) and single jointed (swing axle). There must have been IRS manual cars. Were the IRS manual cars super beetles? It seems the frame head on a superbeetle is seriously different , does anyone ever use a superbeetle frame for our kit cars?

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Sounds like maybe you aren't in US?  Starting in 1969 US destined beetles all had IRS transaxles.  Are you not using a VW pan - if so then go with what it comes with.  You can convert it to IRS.  VS made mostly swing axel Speedsters and convered from IRS to swing axel. Swing axle cars have a narrower rear width (track) so different ring and tires fit under the rear fenders.  Here is a table that shows serial number and transaxle features (as produced).

A front strut Super Beetle chassis can be used.  When VW pan is cut in half, use the front piece from a std bug.  Or carefully remove the SB front bits and weld on the std beetle front pieces (for the std beam) that are readily available (must be aligned properly before welding.

Image result for vw front frame heads

Or find the old (rare) CMC SB conversion pieces. 



Or go with a custom ACME frame or Coolryde's Mendeola front end -

See the source image


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Last edited by WOLFGANG

I can say with experience who ever does the frame head conversion needs to be a true Craftsman, a frame table for exact frame head to chassis alignment is a plus.



                          Pulling the old frame head to get a reference to work from.



                                            Cutting the old frame head out.


                                              Done and my welding was decent 


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Last edited by Alan Merklin
@WOLFGANG posted:

Sounds like maybe you aren't in US?  Starting in 1969 US destined beetles all had IRS transaxles.  Are you not using a VW pan - if so then go with what it comes with.  You can convert it to IRS.  VS made mostly swing axel Speedsters and convered from IRS to swing axel. Swing axle cars have a narrower rear width (track) so different ring and tires fit under the rear fenders.

So, you raised more questions... lol.

I am in the US but one of the manuals I brought with me from the UK. The kit I want to purchase is the customs fiberglass from mexico. I dont know if I can specify what year frame I get as part of the kit. Maybe I can, but just incase I cant, I want to know my options. 
If I got a SA chassis is there welding involved to convert to IRS? Do I need to convert? In your opinion... which is best? I like the fact that camber is a little more consistent with IRS, but I’m not really going to be on the track or off-roading. 
Who are VS? And why did they “down rate” their suspension?
When you say different ring? And tires.. whats ring? Can I get a fatter tire in the rear with a SA? 

Then theres the transmission,  so, if Im getting pot luck on my chassis, can i put any transaxle in there? Or would it need to match the type of chassis? I guess im asking if the mountings are consistent across cases and chassis and can you bolt up either a double knuckled and single knuckled axle to any transmission?

ring is typo tire rim

VS is the old Vintage Speedster out of Hawaiian Gardens.  Vintage Motor Cars is there now.  Like I said going from IRS to SA gives more room in rear for wider wheels and tires.  My CMC is classic body on '71 IRS pan and with Porsche 2L Fuchs (5.5x15") with 185/65x15 tires I have about a 1/4 clearance with rear fenders. So agree SA is handling step backwards but reducing rear track is costly.  No way I could add disc brakes to rear of mine without costly narrowing of rear control arms and shorter axle shafts. Yes welding is require to change from one to another.  Note - the VW pan has to be shorten ~11" and welding is required there too.  

Does a VW pan come from MX with the body?  If so can it be registered in US easily? Bodies and subframe will fit on either IRS or SA VW pan.

Have you looked at used/unbuilt FF/CMC Speedsters in US?  All the bits and pieces you will need to complete your can be quite costly - plus build manuals are readily available.

Info is great ,  thanks. Im being told that swapping out the VIN with a US donar  would be the way to best register a MX kit. One of  my next goals is to get hold of a local inspector from the DMV and set up a meet with him to talk about what i need to do to best register the kit and as what.

Where are the best places to look for used/unbuilt ff/cmc kits? I keep my eye out for unfinished projects but they are like hens teeth.  I really want a coupe too. 

Any transmission from the sixties is good, and can be built as swing axle or IRS. They all have side covers on both sides of the transmission.

I don't remember the changeover year, somewhere between '71 and '73, but after then the transmissions were dedicated to being IRS, and rear wheel drive only. The transmission cases only had one removable side cover for installing a differential. It only went in one side and the other fixed side(part of the case) only accepted IRS flanges/bearings.

All the DSC(double side cover) transmissions could be built for RWD or mid-engine, a simple matter of installing the ring gear from the other side to swap drive direction.

Swing axle is easier and more authentic. IRS is better. Way better, on track or on the road.

Most guys just build what they get. If you have an IRS pan, do yourself a favor and get an IRS transaxle. A later model one is better; they're a little stronger, but like Danny says, any one will do fine in front of 95 percent of the engines you're likely to use if it's gone-through and rebuilt to the normal heavy duty standards.

If you have a swing axle chassis, build a swing axle car. Buy a camber compensator and bolt it on before you get to the road test phase. Swing axle cars handle OK with these, and if it's paired with a good front sway bar you should be able to stay out of trouble.

Now stand by for gear ratio advice. ...

And if you read the last page, you would have learned this:

PostPosted: Fri Apr 10, 2020 9:14 am    Post subject: Re: No more NEW Registrations in Texas?Reply with quote

Saturday, August 12th, 2017 was…
1045 Days
Do I have your attention?
2 years, 10 Months. & 10 Days
How about now?
34 Months, 10 Days
Perhaps now?
However you choose to look at it… that is a LONG time & how long this effort took.
I am sure some of you are thinking to yourself, what the heck is Faron talking about?
I just got word that on June 22, 2020, Assembled Vehicle Owners will be able to start the process of LEGAL Title/Registration of our hobbyist-built vehicles. Yes, you read that correctly! MONDAY, June 22nd, 2020 is when we can start the process of getting our Assembled Vehicles back on the road legally!
I know that June 22nd is 73 Days from today, but nothing has been quick when it comes to working with the bureaucrats at the TxDMV, and then the fact that they are working from home due to COVID-19 adds more time to that equation. We are lucky that its just June 22nd, 2020. Before you ask, the actual guidelines, as well as forms, havenot been released just yet. But I assume they will be released soon. Rest assured, we will get that information out to you soon after we receive it.
That is all for now…

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