Hello from Germany!
 

I recently bought a Golf Mk3 with a bivalent Gasoline/LPG conversion. LPG is about 0.77€ per Liter while gas went over 1.60 € per Liter permanently. So this will save a lot.

I am planning to do some mods to the Golf so it gets more economical. At the first few drives i reached a 31.7 MPG on LPG under normal driving. With hypermiling techniques i reached already 40.1 MPG on the Autobahn ;) On gasoline this would be around 48.2 MPG (20% more fuel consumption on LPG)

The Mk3 is full stock but soon will get lowered down 2.5". The 185/60/14 Allweather tires will be replaced by 175/65/14 Michelin Energy Savers. For the aerodynamics i've got an original rear wing (not elevated), the deeper VR6/GTI front lip and a diesel engine underfloor cover. I already lowered the wipers under the shape of the bonnet. Also the upper grill will be blocked and the lower grill will be blocked in parts. For the alternator i've got a bigger wheel with a 75mm diameter instead of the original 50mm wheel. I'll try to fully cover the whole floor and to install tire spats from an Audi A2.

Motor is a 1.6 liter 75hp with the longest standard 5MT. It can do 60mph at only 2450rpm with the 175/65/14 tires, which is pretty low.

I'm looking forward to report my efforts to you.

Tschüss ;)

Hello and nice to see another LPG fan here! The numbers you mentioned are already quite impressive, did you correct those numbers for the distance that the car is running on petrol (when engine is cold)? That could make a considerable difference when you do a lot of short trips..
I guess the low rpm of your car is a big benefit for the mpg.
With my car it is difficult to squeeze more than 18,5 km from 1 liter (43,5 MPG). With the recent cold temperatures I am happy to get 16 - 16,5 km/l (37,6 - 39 MPG). On the other hand I do mostly country side driving and almost no Autobahn...

The lifetime average is about 17,5 km/litre. Some pics:
Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - Pandaf's Album: Fiat Panda 1.1 LPG - 54 hp - 2006

Would definitely like to see some pics from your car when you have the time to place them.

Freundlichen Grüßen aus den Niederlanden

welcome!!!
sounds like you are on the right track.
dont forget to increase the psi in the tires!

Goede avond Pandaf!

I nearly need no petrol because i force the car to start on LPG immediately. This is possible because i've got an old venturi system installed. The 40.1 MPG run was made completely without using petrol. It was a nonstop drive for 384kms with 22.50 ltr of 60P/40B LPG.

I only use starting petrol early in the morning at 05:30 AM when temperature is under 10°C for the first approximately 300 meters. That's all. After 1600 kms i didn't need 1/8 of a full petrol tank, which is 55ltr. The LPG tank has 44 ltr (net).

You're lucky to have nearly no elevations in your countryside. My 40.1 MPG was driven between 340 and 800 meters above sea level.

Nice Panda :D I had a Punto last year for two weeks with the same engine. I sold it because i got a too good price for it.

I also have a 2002 EU SAAB 9-5 2.0T and a 1996 CAN SAAB 900 II 2.0T. Both tuned to more than 250 hp. The 9-5 runs on Bioethanol (E85). There's also a 1985 BMW diesel 524tdA (E28) in my hands. But i keep it in a garage. Here in Stuttgart i don't get a permission to run it in the city due to the fine particulates. So it remains parked until i move to Nuremberg next year. ;)

The 9-5 is parked since last week. I'll take the Golf as wintercar ;) Trying to save fuel at the same time. The Golf was chaeper than 4 winter tires for the SAAB. ;)

Pictures are soon to come.

@ mcrews: Thanks for the advice. Tire pressure is set to 2.9bar / 42 psi. Surely it could be more but i don't trust these allweather rubbers. Even with 75hp i've got already problems to hold it on the road in some rainy conditions. Will change to winter tires soon. Ordered today ;)

Put some chalk on the tyres' profile, and see where it wears off when driven straight ahead.

You could have overinflated the tyres for the weight of the car, i.e. made them bulge in the center of the thread.

Old car with probably a well worn suspension + high pressure may mean the suspension can't cope anymore.
The rear end on my car is also a bit lively.
(180.000 km on the shocks, 3.5 bar in the tyres)
If it's just the (light) rear end, reduce pressure a bit there - it's not as highly loaded as the front anyway.

Technically the car is OK. It has all services at 15.000 kms for the last 286.000 kms. The ride quality is still excellent.

I blame it to the quality of the tires which are kind of China-Made-pseudo-allweathers. I've got massive understeer in the wet even at low speeds (turning left/right while rolling; accellerating on wet surface). So the front tires can't hold the grip. Geometry was done 1 year ago when the wishbones were changed.

One question: Would a Warm Air Intake work on my car? It's a single point injection without MAF sensor.

Pictures:

http://de.myalbum.com/Foto-V7PUMAML-D.jpg
http://de.myalbum.com/Foto-IN4HXS3T-D.jpg
http://de.myalbum.com/Foto-YDOTWYOT-D.jpg
http://de.myalbum.com/Foto-NMNOWHWY-D.jpg
http://de.myalbum.com/Foto-M63H47QN-D.jpg
http://de.myalbum.com/Foto-HQXGCSTQ-D.jpg
http://de.myalbum.com/Foto-DOEMTQ6F-D.jpg
http://de.myalbum.com/Foto-DKTG8L4Z-D.jpg

The only visible modification by now is the lowering of the wiper arms. Ride height is stock. You can also see in picture n°5 that a WAI is easy to be done because for cold start there already exists a vacuum activated WAI.

Today i changed the original front lip with a VR6/GTI lip. It's 1" deeper. Also i installed a bigger alternator wheel and a longer belt. The original wheel has a 49mm diameter. The new one has 75mm. After 287000 kms it was time to change the gearbox oil. I used Castrol Syntrans Transaxle 75W90.

Ah but here we have the wind!

That is seriously economical driving, but I believe your ambition stretches beyond 40.1 :thumbup:

Thanks for the pics, the cars looks very clean. Is it allowed in Germany to remove your right mirror to reduce frontal area? Here it is allowed if you car is registered before 2010, so I did that. I put a convex mirror on the inside to have some view left, but mostly I just turn my head to check no-one is there ;) I should add a pic of that (the mirror I mean).

My LPG system is with injectors, I should find out a way to trick the ECU to let it think the engine is warmed up so it switches to LPG.

I believe WAI will work as it works for most cars on petrol, at least you should have some benefit from reduced pumping losses and slightly faster warmup. It does have an oxygen sensor, right?

Thanks. Tomorrow i will drive a 500kms run. 2 Persons. Half the way back with 80kgs load. A set of winter wheels/tires.

I will use hypermiling techniques again. The last 2000kms i drove just normal between 33.8 and poor 24.8 MPG

In Germany it is allowed to remove the right mirror as long as you have an interior mirror and one on the left side. I would rather have the right mirror of an Golf Mk IV Cabriolet. Fits perfect and it is much smaller. I don't like the driving without.

Your LPG ECU needs to be programmed at a lower switching temperature. Visit the garage where it got installed. They can do thet easily. Or get an interface for the ECU and do it by yourself ;)

The car has an O2-Sensor.

Did you lower the wiper arms by yourself, or was it done before you purchased the car? How is it done?