1981 Rabbit 1z conversion

rushinrio12

Member
Joined
Jun 29, 2013
Location
Plainfield, CT
TDI
1997 Passat, 1981 Rabbit, soon to become one with each other. Giggity.
At this point, I have more questions than answers about this project and I don't want to start individual threads to ask them. So, the donor car is a 1997 Passat B4 with a 1z engine. The recipient is an 1981 Rabbit 4 door with a 1.6L diesel. I have already learned the answers to many of my questions by reading the build threads of those who have done this before me: vw_nut, burpod, 2many diesels, lugnutgmc, ToddA1, whitegm1, to name a few. My overall goal is for this car to be 95% daily driver and 5% weekend track machine, as I have taken a liking to the SCCA Track Night in America events. I want at least 50 mpg average, low smoke, air conditioning, and at least 125whp. And reliable. Reliability is paramount.

Yesterday, the Rabbit radiator cracked from internal corrosion, so there is no fixing it. I need to continue using the Rabbit as my daily, but I also don't want to buy a radiator that won't work with the swap. My long-term plan is to notch the radiator support for the TDI compressor and use an air-to-air front mount intercooler right behind the grille. I know will need to make custom a/c lines, so the condenser could be whatever fits. The radiator is going to be whatever fits, as well.

What do you think will work best with my intended setup? A 525mm core? A tankless radiator from a 70's Rabbit that eliminates the expansion tank and has a cap on the radiator? I like the idea of the tankless system, as it would clean up the engine bay some and leave more room for the intercooler pipes. Although, the less modification, the better, at least until I start the swap.
 

whitegm1

Well-known member
Joined
Jun 6, 2010
Location
CALIF
TDI
1980 Rabbit Pickup/AHU Diesel, 5spd, 12mm IP, .216 nozzles, 45mpg
Hi
I have the stock A/C unit in the pickup, same problem.
Would like an intercooler sometime, if your diesel is a TDI it will not need the larger radiator that the N/A diesel needs as they run cooler, I am probably going to have a radiator built to accommodate the radiator/ intercooler in the stock location of the the radiator I have now with the intercooler on the passanger side but up and down vertical.
examples;
http://www.rapidford.co.uk/product_info.php?products_id=39
https://ebayapi-loc8apartltd.netdna-ssl.com/00/s/MTIwMFgxNjAw/z/xZQAAOSwzgRW1iXw/$_1.JPG
 

rushinrio12

Member
Joined
Jun 29, 2013
Location
Plainfield, CT
TDI
1997 Passat, 1981 Rabbit, soon to become one with each other. Giggity.
I will be using the 1z TDI engine for this swap. I realize it needs less cooling capacity than the idi engine, which can only help expand the possibilities of radiator solutions, since I can use a smaller one. I know 2many diesels used an MG Midget radiator and Toyota MR2 intercooler side-by-side, and I wouldn't have a problem with that arrangement, but I see that the Midget radiator has different size radiator outlets and locations. I would like to avoid that degree of modification right now, as I am still driving the Rabbit with the IDI engine. I want a radiator that will take me from now, through to the end of the conversion, if that is possible given my vision of the end result. In other words, I want the best of both worlds, I want to have my cake and eat it too, and isn't that the whole idea of a TDI swap in the first place?

Whitegm1, are you using the stock mk1 radiator in your swap? What intercooler are you using? Or are you even using one?
 
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ToddA1

Top Post Dawg
Joined
Aug 3, 2011
Location
NJ 08002
TDI
'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
The smaller non AC cores are not that much smaller than their AC counterparts.

My plan is to go to a Civic radiator which is more vertical than horizontal, but I haven't gotten my hands on one for mock up. Based on available room, I may be forced to have the intercooler mimic the old VW Callaway set ups, where the intercooler was low and horizontal, with a scoop.

The other plan is to go custom cores.... I bought a TIG welder years ago, but only recently opened the package. I'm a little intimidated about the learning curve....

I'd just buy a used radiator, to get you by. If you were local, I say just come by and grab one.

-Todd
 

rushinrio12

Member
Joined
Jun 29, 2013
Location
Plainfield, CT
TDI
1997 Passat, 1981 Rabbit, soon to become one with each other. Giggity.
Geez, thanks for the offer of a radiator, Todd! I would have taken you up on that if I were passing through on the way to my sister's place west of Philly. I think i will take your advice and, for now, just replace what I have, since I need to get it back on the road. I'll either work with it during the swap, or figure out something else.

S-p automotive definitely has a nice solution for my problem. It is also way above and beyond my current budget! Thanks, vw_nut. Will probably order some of their other swap parts, though, just to make the job go quicker.

I'll post pics of both cars soon, just to get this thread rolling, although I have other things to finish before I take the Passat apart. Any special requests of jobs to cover in great detail, so I can plan for pictures?
 

whitegm1

Well-known member
Joined
Jun 6, 2010
Location
CALIF
TDI
1980 Rabbit Pickup/AHU Diesel, 5spd, 12mm IP, .216 nozzles, 45mpg
rushimrio12,

I am using a u tube instead of an inter-cooler and this works well, the aluminum tube for the turbo discharge AHU has been cut/shortened and tig welded back together,
I am using the stock radiator at this time, I will more than likely do the radiator that I described when the first timing belt replacement happens in 30K mi,
I like you use the pickup, more than my other 5 vehicles due to the huge economy, and other than engine parts , all parts are cheap, not to mention a kick to drive.

VW-NUT
i looked at the radiator that SP Automotive has and it is nice, due to stock hoses, and I am set up to plumb the inter cooler pipes on the passenger side I will still seek a vertical arrangement, Thanks Mark
 
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ToddA1

Top Post Dawg
Joined
Aug 3, 2011
Location
NJ 08002
TDI
'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
Geez, thanks for the offer of a radiator, Todd! I would have taken you up on that if I were passing through on the way to my sister's place west of Philly.

If your local family will be visiting you, have someone stop by. I'm sure I have several decent used rads.

-Todd
 

rushinrio12

Member
Joined
Jun 29, 2013
Location
Plainfield, CT
TDI
1997 Passat, 1981 Rabbit, soon to become one with each other. Giggity.
Whitegm1,
I love driving my car also. I love the simplicity and efficiency. The TDI will only improve on that. I definitely want to plumb in an intercooler. You're using the mk1 condenser also?

Todd,
I appreciate the offer. I may send someone for a rad. Would mk1 a/c controls be capable of controlling the AHU compressor? My mk1 controls are somewhat broken and the Passat temp knob is missing, so I still need something for HVAC controls. What do you recommend? What might you have kicking around collecting dust?
 

ToddA1

Top Post Dawg
Joined
Aug 3, 2011
Location
NJ 08002
TDI
'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
I can't see why the A1 dash piece wouldn't work the compressor. It's just 12v to the clutch.

Those knobs should be easy to find, but if you want the A1 part, best to search the classifieds, eBay, etc. I've noticed the AC ones aren't as common as non-AC. You'll find that the temperature slider track is worn through/broken on most/all of them. In 20 years, I don't think I've ever owned a Rabbit where it wasn't. My plan was to fix it with metal, Quik Steel, etc.

I haven't gotten to this point yet, but I believe if you're going to use the A1 TXV, you're going to need to open the compressor to go fixed displacement. In current form the A3 compressor's refrigerant valve relies on the newer TXV. Pretty simple procedure, that's searchable.

Swapping to an earlier compressor head may make hose fabrication a bit easier. I've been looking to get a hose crimper, in the near future. If I do, I may rent it out.... not sure if there's any demand.

Lmk about the radiator.

-Todd
 

rushinrio12

Member
Joined
Jun 29, 2013
Location
Plainfield, CT
TDI
1997 Passat, 1981 Rabbit, soon to become one with each other. Giggity.
Finally time for some eye candy! Just a teaser, though. No swap work has been done yet. My friend is supposed to come over this weekend so we can start planning and organizing with the Passat and Rabbit side-by-side. I hope to get a lot done, but I also know I need to pace myself. This project will take awhile and I need to stay organized. There will be much labeling and writing of notes. Perhaps more pictures!











 
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rushinrio12

Member
Joined
Jun 29, 2013
Location
Plainfield, CT
TDI
1997 Passat, 1981 Rabbit, soon to become one with each other. Giggity.
Todd,

Since the weather is fairly consistent, I think I'll cap the vacuum supply for the HVAC controls and try to repair the slider track on my mk1 controls since they should be capable of controlling the compressor. Jb weld maybe?

I don't fully grasp what you're​ talking about with the txv, since I don't understand a/c as well as I should. I'll have to do more research on that. Thanks for bringing it to my attention, though. I never would have thought about that! Could you provide more details about swapping to an earlier head? What is the difference between the B4 head and the earlier head? And where can I find an earlier head?

My mother just drove out to Pittsburgh, but she won't be going that far south this time. I'll probably be the next person going through there that I can convince to stop and stuff dirty used car parts in the trunk for the ride home. That's okay. I want to see your Rabbit up close anyway.

Ed
 

2many diesels

Veteran Member
Joined
Mar 20, 2011
Location
Nor Cal
TDI
rabbit pickup 1z swap Audi A4 Quattro ALH. 02 Beetle TDI. 99 Golf TDI. 03 Wagon TDI. 914 Porsche ALH t
The mk3/b4 compressors are variable displacement. They have a swashplate inside that moves via the refrigerant control valve to vary the displacement, thus these use a different type of expansion valve.
The issue is not with the head on the compressor rather the control valve. The solution is to remove the control valve (which are problematic on a good day) and replace it with a 7/8 bolt if i remember right. Then you can use all of the mk1 ac goodies....once you get adapters for the compressor.
 

ToddA1

Top Post Dawg
Joined
Aug 3, 2011
Location
NJ 08002
TDI
'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
Ah, I'm glad you went through the hassle of explaining it! I think I'm sticking with the VD style. I like the fact that the compressor doesn't cycle on and off.

I suggested the head swap to make hoses a bit easier to make. I figure the metal parts already have the correct bends.... haven't gotten to that point yet, so I'm still undecided.

-Todd
 

rushinrio12

Member
Joined
Jun 29, 2013
Location
Plainfield, CT
TDI
1997 Passat, 1981 Rabbit, soon to become one with each other. Giggity.
Friday was different for me. Near the end of the work day, I was coming back from a road test and a Jeep rear-ended the bus I was driving. The Jeep tipped onto its side after the impact. The guy climbed right out of it and he was fine. It didn't seem like that bad of a hit for me, but my back has been getting worse every day since. My friends Mike and Drew came over Saturday and they got done basically what I wanted to this weekend. Thanks, dudes! Tons of labeling and disassembly. The powertrain is just held in by the mounts at this point, unless something was missed. We'll find out soon. I think we will be dropping it out of the Passat. It looks like the engine and trans would be too wide to pull up as an assembly. I'm so ecstatic to see progress on this!



Thanks for explaining the A/C workings to me, 2many diesels and Todd. I'm still not fully grasping the concept, but I haven't done any further research yet.

For my application, the only accessory I am deleting is the power steering. I have done much research for an AHU swap into a Vanagon, where my intent was to delete A/C and P/S, and I know about using a VR6 water pump pulley to run only the serpentine belt. What will I need to do to eliminate the P/S and v-belts for my application?
 
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rushinrio12

Member
Joined
Jun 29, 2013
Location
Plainfield, CT
TDI
1997 Passat, 1981 Rabbit, soon to become one with each other. Giggity.
How do you guys add photos to your threads? I like to think I'm okay at this tech stuff, but this website is proving me wrong.
 

whitegm1

Well-known member
Joined
Jun 6, 2010
Location
CALIF
TDI
1980 Rabbit Pickup/AHU Diesel, 5spd, 12mm IP, .216 nozzles, 45mpg
Photo bucket website, copy url to your posting page.
 

sriner

Well-known member
Joined
Nov 19, 2012
Location
Virginia
TDI
96 Passat TDI
The mk3/b4 compressors are variable displacement. They have a swashplate inside that moves via the refrigerant control valve to vary the displacement, thus these use a different type of expansion valve.
The issue is not with the head on the compressor rather the control valve. The solution is to remove the control valve (which are problematic on a good day) and replace it with a 7/8 bolt if i remember right. Then you can use all of the mk1 ac goodies....once you get adapters for the compressor.
This is the first I've heard of this. I tried searching but haven't found much yet. So in order to use the MK3/Mk4 AC compressor with Mk1 body AC components the MK1 expansion valve or a control valve on the MK3/MK4 AC compressor needs to be changed/modified?
 

jimbote

Certified Volkswagen Nut
Joined
Jul 10, 2006
Location
spiral arm, milky way (aka central NC)
TDI
Tacoma 4x4 converted to TDI
How do you guys add photos to your threads? I like to think I'm okay at this tech stuff, but this website is proving me wrong.
forget about photobucket...they just banned all third party hosting unless you pay $400 ....I'm in the process now of loading my pics onto the TDIclub server so I can replace the broken photobucket links with TDIclub hosted pics ....it's not very hard to to, just log into the club's photo server using your ID and password...choose the "upload photos" option ....hit the "browse" button and double click on the photo you want to upload...you can choose ten to upload at once...once loaded you click on a thumbnail and either choose direct link or IMG code for imbedding the photo into your thread .... clicking on the little box just to the right of the "linked thumbnail" window will show you these options
 

rushinrio12

Member
Joined
Jun 29, 2013
Location
Plainfield, CT
TDI
1997 Passat, 1981 Rabbit, soon to become one with each other. Giggity.
Amazing! It seemed like I should be able to get those pics onto this thread. I just couldn't connect all the dots. I'll have to go back and edit my posts so they actually show pictures. Also, I need to post an update, though the going has been slow it in the garage lately. Thanks, Jim. The picture can stay as proof of your hard work.
 
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