Proposal for an tune on my Tahoe 5.3 2007 LTZ (Germany) with LPG system

[DJPoertsch]

Hello, dear community and professionals. Currently, I've bought an I1000 on eBay and already turned off the DOD under the Stock Tune.

Now, my question for you. I myself live in Germany and will often be traveling with a caravan now. Which further tuning would you recommend to me to get a better performance. Or do you have any tips that will make my Tahoe a little fresher?

I would like to mention that I installed an LPG system from Prins VSI 2.0.
It is very common in Germany to make such a conversion because of the high fuel prices.

That's why I did not dare to go to the Octane Tunes.
I would be glad if you had tips and could tell me your experiences.

I know that my diabolo Tune handheld give me options for Octan tune. Butt I was insecure to change here something, and later on I have more problems. I had a very high consumption of LPG with my caravan last week. About 27 litre LPG for 100 km seems very high.
I also often I had the issue that my Tahoe would repeatedly increase to over 3500 rpm on steep mountains. It always sounds like it's about to explode. Especially when you're used to driving on the highway, you only have to drive at 1500 rpm. I know that a diesel is probably the better alternative here, especially since it produces a good amount of newton meters at low speeds. Hence, my question whether I can do something so that my Tahoe doesn't have to suffer so much, especially with LPG.

Thank you for your answers, my experts.

 

[Joseph Garcia]

@BlackBearPerf may have a suggestion.

 

[j91z28d1]

I know very little about propane except some forklift trucks we have but nothing about converting a gas engine to propane.

do you know what all is involved with this Prins VSI 2.0 kit? it might help a bit to know what you're dealing with. is it all add on stuff with a stand alone controller for fuel or does the factory ecm get reflashed to tune it for the different fuel?


just a guess, but if it's all add on mechanical kit and the ecm is running the timing, being propane I believe is higher, quick google search says it 104 octane. so if you have the corresponding amount of fuel, I'm guessing you could increase the timing over stock for a bit more power.

but it's all a guess really. that said, 3500rpm up a good grade while towing a heavy load sounds pretty normal. the guys that tow here will probably chime in with what they see while towing. but I'm pretty sure constant 3500rpm will not hurt your engine.


fuel mileage, someone with much better math skills than me will have to convert all that into what we are used to seeing to maybe know if your tow mileage is normal.

 

[Geotrash]

Hello, dear community and professionals. Currently, I've bought an I1000 on eBay and already turned off the DOD under the Stock Tune.

Now, my question for you. I myself live in Germany and will often be traveling with a caravan now. Which further tuning would you recommend to me to get a better performance. Or do you have any tips that will make my Tahoe a little fresher?

I would like to mention that I installed an LPG system from Prins VSI 2.0.
It is very common in Germany to make such a conversion because of the high fuel prices.

That's why I did not dare to go to the Octane Tunes.
I would be glad if you had tips and could tell me your experiences.

I know that my diabolo Tune handheld give me options for Octan tune. Butt I was insecure to change here something, and later on I have more problems. I had a very high consumption of LPG with my caravan last week. About 27 litre LPG for 100 km seems very high.
I also often I had the issue that my Tahoe would repeatedly increase to over 3500 rpm on steep mountains. It always sounds like it's about to explode. Especially when you're used to driving on the highway, you only have to drive at 1500 rpm. I know that a diesel is probably the better alternative here, especially since it produces a good amount of newton meters at low speeds. Hence, my question whether I can do something so that my Tahoe doesn't have to suffer so much, especially with LPG.

Thank you for your answers, my experts.

Hello Markus, nice to see you here again.

Doing the math to convert your numbers to the ancient English system we sadly still use here in the US, I calculate an equivalent of 8.41 mpg. Given that LPG consumption is typically 84% of petrol consumption in vehicles, I calculate that you're getting about 7.07 mpg equivalent, which is only slightly less than I get with my 2 Yukon XL's, where I typically see 7.5 mpg when pulling our 7500 lb (3400 kg) camper. You might be able to tune it for a bit better mileage, but you're pretty close to what I would expect at 70 mph (112 kph), depending on the size and weight of your caravan.

 

[DJPoertsch]

Hello everyone @Geotrash , @j91z28d1 . Yesterday I wrote to my LPG professional and converter again. He also told me that it would be typical behavior if you wanted to climb mountains with a wall unit attached to the back. Since LPG has a higher octane value, but a poorer energy density than gasoline, he advised me to temporarily switch to gasoline and to temporarily avoid the deviation in performance. Therefore, everything seems normal. It's just unusual if, like me, you drive comfortably on the freeway at 130 kmh at 1800 revolutions and only hear the engine hum slightly and then in the trailer mode on the hill you think you're driving an F16 fighter jet.

 

[Geotrash]

Hello everyone @Geotrash , @j91z28d1 . Yesterday I wrote to my LPG professional and converter again. He also told me that it would be typical behavior if you wanted to climb mountains with a wall unit attached to the back. Since LPG has a higher octane value, but a poorer energy density than gasoline, he advised me to temporarily switch to gasoline and to temporarily avoid the deviation in performance. Therefore, everything seems normal. It's just unusual if, like me, you drive comfortably on the freeway at 130 kmh at 1800 revolutions and only hear the engine hum slightly and then in the trailer mode on the hill you think you're driving an F16 fighter jet.

Yes, the higher RPMs definitely take some getting used to - especially with the 4-speed transmission in the 2007 5.3 rigs. It's a bit better with the 6-speeds in the later model years. I find that towing in 4th with the 6L80 is the sweet spot with my two Yukon XL Denali's. It holds 2800 RPMs all day until a really big hill and then it might drop to 3rd for a minute or two.