Audi S4B7 4.2L, V8

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Audi S4B7 4.2L, V8

#1 Post by Stixman » Sun Dec 29, 2019 1:12 am

Hi I am sorry but I am new and I am no good at navigating this site.I want to convert my 4.2l Audi to lpg but I am getting conflicting advice on which is the best system to install,please help.

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Re: Audi S4B7 4.2L, V8

#2 Post by Gilbertd » Sun Dec 29, 2019 10:04 am

Which system is far less important that how it is installed and calibrated. What engine and how old? I think most of the later Audi engines are direct injection which limits your choices considerably.
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Re: Audi S4B7 4.2L, V8

#3 Post by Stixman » Mon Dec 30, 2019 10:32 am

Thanks for your reply Gilbertd, my Audi is a 2007 S4 and it is not direct injection, just sequential injection.

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Re: Audi S4B7 4.2L, V8

#4 Post by LPGC » Mon Dec 30, 2019 11:10 am

I've converted an Audi S4 with the 4.2 port injection V8, a year older than yours, quite a long time ago though... converted it in 2009 when it had only 30000 miles on the clock.

These days I'd use a different set of components which were not available then. There's nothing unusual about the engine except it uses some none standard heater pipe sizes (may be helpful to have some unusual size water pipe T's / adaptors to plumb the reducer in to minimise water pipe lengths and help make for a neat installation), the engine bay is a bit tight.

Plenty ideas on what components I'd fit if I were converting another but I'd tell a potential customer that it would be better to have me try a range of components (injectors / reducers) from a shortlist of good/reliable components that suit the car/engine in a technical sense before deciding which to fit on the basis of physical fit / neatness of install. The only bits I know for sure I'd advise for this car are KME Nevo electronics, if a potential customer pushed me to decide on components before seeing the car it wouldn't really be a problem (I could advise bits off the cuff) but the majority of my customers would think it better that I decided after looking around the car. Wouldn't really be a problem if the customer dictated which components they wanted fitting (chose their own full set of components) but I'd draw the line if they dictated parts that might effect end results too much.

An amateur won't have different components around to offer into positions on the car etc, will find if difficult to steer through installers/suppliers/manufacturers hype about components specs, won't know what real world specs will best suit the vehicle and it's engine... But in all of those respects amateurs are in the same boat as most installers anyway! lol ;-)

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