[V8] LPG con version, or if it's too good to be true, the Audigods will stuff it up your nose

[Mike Arman]

On 3/4/2012 5:19 AM, Roger M. Woodbury wrote:
> This sounds too good to be true. A perfect solution to an awful problem and I am certain that Audi
> has already angered the Audi gods by thinking about an LPG conversion themselves.


> Now, having said that, it IS the perfect solution to a lot of problems....at least I think so. The
> only issues that I can think of is the fuel delivery problem,



Roger,


(copying this to the list, it is pertinent information)


Up late last night playing on the net with this.


Found a COMPLETE installation manual for one of these systems, 56 page illustrated PDF, even in 
English, covers *all* details. Google may be awfully nosy about my privacy, but they ARE useful.



  the tank location problem,


Forward area of trunk - use 24 gallon horizontal tank. Subframe/bracing/cage needed, "certificated" 
conversions are supposed to absorb 20G longitudinal, 8G lateral, so can't mount the tank with 
bungees. This isn't a HUGE problem, one more item on the to-do list.



  the reserve
> tank location and how that would be plumbed,

None.


  and the loss (minor, MAYBE) of additional lubrication
> in the engine.


Some of the UK converters add a top end lube system. Most of them say German cars don't need it (but 
are happy to install it anyway for more money) because the valve seats are harder in German cars. 
Problem is (may be) erosion of the valve seats.


> Oh, yes. And the insurance problem. IF there is an insurance problem, of course. I have NO idea how
> insurance companies look at engine or fuel conversion projects in this day and age.

None known. Minor information found that most don't care.

Can't drive through the Chunnel (awwwww) or go on some European car ferries (awwwww again). I do 
seem to recall a prohibition on the Delaware Bay Bridge regarding compressed gasses in tanks, but 
that was almost 40 years ago.



> If the choice is between looking at a major fuel system revamping and ripping out the whole system
> and replacing it with an LPG system, and you have the knowledge and patience to do the work, I say,
> GO FOR IT.

It is looking like I will.



> On the other hand, unless the car is near perfect, it might be the end of the road for the poor
> dear...no, no, no. I don’t want to even think about that!


The car is nice - body 99.5% perfect (one or two very, very minor dings/stone chips, you really have 
to look for them), the interior is 99.5% perfect (not new, but all there and untorn, clean, 
everything fits, headliner up properly), all systems work (!), no leaks, relayed eurolights, A4 
wheels with spacers, properly working UFOs, clean, straight car. Fresh timing belt and ALL ancillary 
parts.


I need to change the radiator (have one) because it is starting to clog, I'll change the timing belt 
again (timed out, not miles), and if I really wanted to spend some money, I'd change the WS because 
it is somewhat sand-pocked. And the parking brakes don't work - standard equipment.



It appears there are a LOT of conversions running around Euroland. The owners appear to be very well 
satisfied with them. The "best" (or at least the most expensive - about $3K installed - and best 
advertised) is by Prinz LPG, and there are several on A8s. Look at eBay.co.UK for a lot of parts. It 
appears that I'll be able to buy the LPG injector set (pair of 4's) for something like $250, the 
regulator is another $150, and ebay here has new 25 gallon propane tanks for $150ish.

EPA gives a free pass to these PRIVATELY DONE NON-COMMERCIAL OLDER CAR conversions as of 4/11 as 
long as the emissions from the converted car are lower than the original car. That's problem #1, the 
original car isn't running, so I have nothing to compare it to. It may be a non-problem, we'll see.

EPA also says if the car has OBD-2 it has to work - this one doesn't, I think the OBD system is 
version 1 (has non-standard connectors), so exempt.


Problem #2 is the pre-heat. Most of the conversions use the gasoline system to start the car and get 
the water temp up to 50C, whereupon the vaporizer will work. I want to GET RID of the gasoline 
system entirely, so I'll either need to see how they work this on air cooled cars (they've done some 
Porsches) or make up a small, electric pre-heater with a couple of tees and a thermostat. I have not 
decided how to approach that problem yet.

The injectors will be run by a Megasquirt - I have one, and they will run LPG injectors, there are 
several LPG-fuel successes on the Megasquirt site - fuel mapping is different, which is why I need 
the MS system and can't run off the stock ECU.



More to follow . . .



Best,

Mike



> Roger