TheSamba.com :: View topic - Heater Box/Exhaust conversion from 77 to 72-74 Question

Fri Apr 25, 2008 6:51 pm

My 77 bus (GD engine) is in for a rebuilt engine (JCS) and i am replacing my heater boxes at the same time. My question is that my vw service centre is recommending I go to a 72-74 heater boxes and exhaust as it has less places to leak and is simpler to maintain - he had a point that VW went back to the 72-74 heater box style in 79. I'm in Canada and have no catalytic requirements and my bus does not have one anyways...

I was leaning towards keeping my bus stock but as 77 parts (heater boxes,seals, gaskets, exhaust tubing) become harder and harder to get this may make sense???

At first I was reluctant to do this but my vw vendor has lots of experience and is well respected in the local vw community....he said that if it was his bus he would do this change ..

I would really appreciate any thoughts on this...

Thanks!

Todd

Fri Apr 25, 2008 7:03 pm

Common to do and I did the same thing. They breath a little easier.

The heater box to the exhaust header meet at a "trapezoid" flange....

http://images.thesamba.com/vw/gallery/pix/350011.jpg

Fri Apr 25, 2008 7:07 pm

I have been a total slacker on this project. I have had my 72-74 boxes and muffler for 2 years and havent put them on.

Fri Apr 25, 2008 8:17 pm

77westy1 wrote:
I would really appreciate any thoughts on this...

Aside from breathing easier, it is a simpler system. The '75-'78 stock system consisted of two manifold pipes (NLA, expensive to find ones with good flanges), two "U-PIPES" (NLA, last I checked reproductions were $150 each), two heater boxes (available as aftermarket replacements), crossover pipe, elbow pipe, catalytic convertor (or eliminator pipe), muffler, and tail pipe. There are MANY connections in this setup.

The '72-'74 style consists of two heater boxes, a muffler, and a tailpipe.

If you already have the existing '75-'78 style, IMHO it's not worth replacing for the sake of replacing. If you need to replace any expensive part of the system, such as the heater boxes, it likely makes sense to do the swap.

Make sure you replace all the necessary tin bits as well. Scott from GermanSupply.com lists a KIT for doing the swap, but he may be out of stock. All of the components in his kit here: http://www.germansupply.com/home/customer/product.php?productid=16683&cat=409&page=1 are needed!

Fri Apr 25, 2008 8:40 pm

Besides the heater boxes and muffler, you will need 8 pieces of tin that also includes the alt support. BUT...... the pieces are getting tougher to find. Scott put them all together here: http://www.germansupply.com/home/customer/product.php?productid=16683&cat=409&page=1
but I doubt he has them all....

Fri Apr 25, 2008 9:15 pm

thanks everyone so much for the comments!!! - i know he mentioned something about some tin and not being available..but I didn't get the impression it was a big issue for the conversion without it...

my quote doesn't seem to have the 8 pieces for the conversion listed - so i'll definately have to check with him about how he was planning on doing the conversion - with them?? or without these pieces?? - or if the pieces were included as part of the total???

Thanks again!

Fri Apr 25, 2008 9:53 pm

77westy1 wrote: thanks everyone so much for the comments!!! - i know he mentioned something about some tin and not being available..but I didn't get the impression it was a big issue for the conversion without it...

my quote doesn't seem to have the 8 pieces for the conversion listed - so i'll definately have to check with him about how he was planning on doing the conversion - with them?? or without these pieces?? - or if the pieces were included as part of the total???

Thanks again!

It is a big issue. You NEED all of them.

Fri Apr 25, 2008 10:22 pm

karl wrote: It is a big issue. You NEED all of them.

Thanks Karl!

i will call my vw vendor on monday and if he doen't have, can't get, or doesn't intend to use all the 8 conversion parts then i'll get him to replace just the 77 stock Heater boxes (assuming all the rest is good) and leave the exhaust as 77 stock for now....

Fri Jul 18, 2008 7:14 pm

Can you run a Cat and EGR with the 72-74 setup on a 77?

Fri Jul 18, 2008 8:29 pm

RZAR wrote: Can you run a Cat and EGR with the 72-74 setup on a 77?

EGR yes: if you use a 411 muffler or find the super rare left heater box with the EGR filter flange on #2 exhaust pipe. A minor problem with the 411 muffler is the spacing of the EGR filter flange: 411 is closer together. Somewhere I posted pics and measurements but I cannot find them.

Cat: no way, no how.

Sat Jul 19, 2008 9:24 am

What about using the cross over pipe from a Fed 79-83?

Sat Jul 19, 2008 9:29 am

yes, that should work. 72-74 HE, 79 x-over, cat, stock muffler and tailpipe.

Sat Jul 19, 2008 9:31 am

EGR too?

Sat Jul 19, 2008 9:33 am

to include EGR you'd have to fashion something to get the egr into the exhaust stream or use an early setup and have the egr plumbed into the HE exhaust pipe like karl mentioned. there's no EGR 79-up.

Sat Jul 19, 2008 9:39 am

OK thanks for the info. I ask this because I scored a complete CB engine with perfect HE's. I was thinking on using them on my 77 since they flow better. But it doesnt seem to be worth it because the ones on my 77 are in great shape too. Thanks to Karl for the awesome manifolds!

Sat Nov 15, 2008 3:36 pm

Thread Ressurection!!!

OK, I am 2 pieces away from being ready to do this swap. I need to know what the bottom two pieces of tin are called and where they are located on the engine so I can track them down (see bottom 2 photos in germansupply.com link)

http://www.germansupply.com/home/customer/product.php?productid=16683&cat=409&page=1

Thanks...

Sat Nov 15, 2008 3:42 pm

Karl wrote: RZAR wrote: Can you run a Cat and EGR with the 72-74 setup on a 77?

EGR yes: if you use a 411 muffler or find the super rare left heater box with the EGR filter flange on #2 exhaust pipe.

do you mean coming off #4 as seen in this pic?

Sat Nov 15, 2008 5:25 pm

RZAR wrote: What about using the cross over pipe from a Fed 79-83?

Ding.. Ding...Ding

You win! That is the answer.

I have been searching for the 79 Fed Bus and/or the 80-83 Fed Vanagon crossover pipe for some time. BD used to carry a repo but no longer. Used is even tougher to find at least for me here in Cali.

There has got to be a boneyard somewhere with a few of these. I'd take one even if it didn't have the EGR tube. I'll work that out later.

I have the HE's, tins, and alt bracket. Need the crossover pipe.

Sun Nov 16, 2008 10:50 am

EZ Gruv wrote: Thread Ressurection!!!

OK, I am 2 pieces away from being ready to do this swap. I need to know what the bottom two pieces of tin are called and where they are located on the engine so I can track them down (see bottom 2 photos in germansupply.com link)
http://www.germansupply.com/home/customer/product.php?productid=16683&cat=409&page=1

Thanks...

Sun Nov 16, 2008 11:01 am

EZ Gruv wrote: EZ Gruv wrote: Thread Ressurection!!!

OK, I am 2 pieces away from being ready to do this swap. I need to know what the bottom two pieces of tin are called and where they are located on the engine so I can track them down (see bottom 2 photos in germansupply.com link)
http://www.germansupply.com/home/customer/product.php?productid=16683&cat=409&page=1

Thanks...

They are O and U here: http://www.bus-boys.com/aircoolsystem.html#tin

I may have them.