[Che]

I'm trying to get the car running as lean as possible - albeit i'm running LPG, but the concept is the same unless someone can tell me otherwise.

I'm running the car lean to the point if I back off any further the idle starts to get a little erratic. It's worked wonders economy-wise and I got an extra 75km out of the last tank.

Car's temp guage not heating any more than it ever did (sits on around 1/3), which to me would be the first sign of an unhappy engine. Are there other signs I should keep an eye out for?


Wondering if I should keep the mixture screw where it is or back it off a little so it's a bit richer. I mean, ecomony is great, but engine lifespan is just a little more important.

[ball]

A lean burn will give you less power.

A suzuki is way underpowered as it is, why would you want to reduce it any further.

[whincup]

economy... some people just dont care about power, and honestly if you drive a sierra then clearly you really dont... some people just want to be as economical as possible.

i dont know much about LPG, but to me i would think that it COULD start drying out the seals, etc... but again, i could be way off. maybe you should discuss it with whoever fitted the system to your car... or better yet, someone here smarter than me.
and as you said, temperature, which you said isnt an issue at the moment...

[royce]

Lean engines make for hot exhaust valves, this is why gas has a bad rep cause they are normally lean from poor metering

youll also lose efficiency which makes fuel use go up cause you need more pedal for the same power to push you along, there are set ratios that are right for power, right for efficiency and right in theory, deviate from any and you wont make any improvements

in a petrol engine the HC emmision values also go way high, thats unburnt fuel in the exhaust due to to lean a mix not burning fully

[Che]

How much does off timing affect economy?

I mean, now my gas system has settled in, i've found i'm chewing around 14 - 16L of LPG per 100kms, which is about 2L more than I should be considering i'm basically a stock car thats small and weighs zip.
The first two tanks I got 600kms, but since then i'm lucky to get 500 - seems a little strange to me.... maybe the installer put a little magic gas in the tank first time around, but I suspect my timing is off.


If i'm running slighly negative timing what would be the signs/effects? I mean - I know if it's way off its unbearable, but how to tell if it needs just a little tweak? How to tell if its at its optimum? I can just tell something isn't at 100%

[eldo]

Maybe you should join an LPG forum, if there is one

[eldo]

Google it they do exist

[ball]

che_guitarra wrote:

How much does off timing affect economy?

I mean, now my gas system has settled in, i've found i'm chewing around 14 - 16L of LPG per 100kms, which is about 2L more than I should be considering i'm basically a stock car thats small and weighs zip.
The first two tanks I got 600kms, but since then i'm lucky to get 500 - seems a little strange to me.... maybe the installer put a little magic gas in the tank first time around, but I suspect my timing is off.


If i'm running slighly negative timing what would be the signs/effects? I mean - I know if it's way off its unbearable, but how to tell if it needs just a little tweak? How to tell if its at its optimum? I can just tell something isn't at 100%

Dyno with a good operator.

That is shit fuel economy. I can get a 202 holden 6 in a big car to run better than that.

If you are chasing economy then you are starting with the wrong car. Find a late model engine with efi and start from there.

[royce]

more timing you can safely run the better, but unless you are a guru and have a dyno youll never get it right, I suggest that although as fun as it might be fiddling you are jsut stabbing in the dark, take to a dyno place that knows gas and get the dizzy recurved to suit and the mixtures setup for best cruise then leave it alone

[eldo]

royce wrote:

more timing you can safely run the better, but unless you are a guru and have a dyno youll never get it right, I suggest that although as fun as it might be fiddling you are jsut stabbing in the dark, take to a dyno place that knows gas and get the dizzy recurved to suit and the mixtures setup for best cruise then leave it alone

I agree

[Che]

I'd have gone EFI, but in the end a decent LPG system is cheap to install, it's still cheaper to run than EFI, cheaper to maintain should something go wrong, and the power gains are there. I couldn't afford the cost of an EFI install anyway... the missus would have to go hungry for three months. Even Jesus only lasted 40 days!



I'm not really chasing power gains though, I just want the 1.3 I have to be running like a swiss watch. A dyno shop is just the ticket I think. Any recommendations in Brisbane north?


How much should I expect to pay for dyno tuning and a dizzy recurve?