LPG Explained... An Intro to LPG

[oldcorollas]

a link linked from PF that i had seen a while ago and forgotten about...
hmmmm, i gess he didn't take into acount that the contents of normal LPG are varied with season (as is petrol)
http://zymo.homemail.com.au/bmw2.htm

[BrianRA23]

I am not sure if it still the practice but I have heard that when a LPG tanker leaves the refinery in Perth they just stop off at the Butane tank to top up, which is why the concentrations can never be clearly defined.

One way of determining the ratio would be to a pressure sensor (though illegally). Additionally a temp input would be required, but this could help solve the tuning issue.

One of the great features of LPG on a daily driver (when using a converter) is that if you ever drop your coolant the converter freezes over and the car stops. This is much better than cooking your engine.

Running LPG only on your old engine allows you to run the long EFI style manifolds for much better low down torque. After converting an XF to LPG we removed the carby and manifold, fitting an EFI one with the mixer now on its side. Straight out the driveway it did its first ever burnout on the bitumen, unintentionally.

[love ke70]

nice thread peoples, am lookin at getting the 1ggte on lpg tuned in the next few weeks, and whenever i call people and say GRA carby running blow thru needs a dyno tune to get mixtures right, most places wont touch
any tips, tricks to get people to play ball?
from memory i think i found 1 or 2 ppl to do it around the $300 mark...sound fair?

just on a side note, what are these "lambada" figures? last time i checked lambada was a latin dance :S
and how do i know the tuners are checking these properly etc? because it seems this is whats gonna stop me making toast of myprecious new valve stem seals...

[Grega]

loveke70..........go to somewhere that specialises with GRA stuff.
any old joe blo won't understand how the choke works nor the progression or idle circuits on the darn things.
if 300 is from a GRA specialist then thats not too bad.

not lambada. lol. is lambda.
tuners normally use lambda sensors (basically very quick response o2 analysers) to check mixtures during tuning...normally there is a glaring red box with figures telling em numbers on how rich/lean the car is that they keep an eye on.

[love ke70]

alrighty, that works for me
on the GRA website there are only 3 places they recognise in queensland but i may do some calling around and see what else i can find
thanks for the help

[stradlater]

Have you called the places that they recognize in QLD?

You are best of going somewhere that knows about GRA. I've had plenty of wasted conversations with guys who don't know sh!t about them.

As for the lambda sensor, you can infact by yourself one off ebay, but the only good ones are very expensive..
:-)

[love ke70]

yes i did call them, one had changed named and seemed to have cracked the beers open a bit too early that day, one had a que of forever and the third told me that you cant run lpg with forced induction
i may try again when im ready for a tune as this was a few months ago that i called around

[stradlater]

Can't run LPG with forced induction.

Best they be having a look at my website....

F'ing tools.

[love ke70]

correcta mondo, and have you noticed GRA now does not offer tech support for people with blow thru setups, its still covered in their tutorial but "its not a recommended practice" according to an email from one of their people i got

[stradlater]

So they only support suckthrough?

[love ke70]

thats the gist of it, ill see if i can dig up the email...

[love ke70]

ME: ask something about who to contact to get to tune as i cant get many people to do it

THEM:
Andrew,

"Blow-Through" forced induction is not something our carbs were designed for, so
they can be difficult to tune and unpredictable.

Try Tony Motsons Performance Centre, (07) 3277 7766

Thankyou for your enquiry.

Shane Vallely

GasResearch Pty. Ltd.
1800 550 335


ME:
ok, thanks for that
ive heard of a large number of people using these carbs as blow through, and
in the tutorials on your website it shows you how they need to be set up to
run blowthru. ie. with a balance tube. why is it you say theyre not designed
for it?
cheers, andrew

THEM:
Andrew,

We did have an information file on the website which explained how a gas
system would need to be pressure compensated when running under boost, but
we can accept no responsibility for the use of our system in this manner.

Thankyou for your enquiry.


so in no uncertain terms, they say it can be done but theyre not interested in hearing about it...

[stradlater]

No, what they're saying is, it can be done, but if you BREAK it, they won't cover you.


I spoke to one of thier techs a long time ago about it, and they said they had only done it in their test environment for up to 18psi or something.

They don't cover things like strengthening the converter diaphragm or putting steel converter hats on the converters.

[love ke70]

i didnt know they covered anything anyway, but i think we are digressing
ill contact tony motsons in a week or 2 when im ready for a tune and see where we go from there