turbo propane set up

[bumpstart]

nah impco 200 still do it easy at .75 to 1 bar boost

[gearhead]

nah impco 200 still do it easy at .75 to 1 bar boost

haha, guess there is more than one way to skin a cat. Well, i'll cross that bridge when I get there. thanks for the info!

[gearhead]

What operating temp does a propane run the most efficient at? My father in law said to me today you want a propane engine to run at 170 degrees F. It seems pretty cool, but i'm wondering what you guys think about that?
He was a propane licenced installer years back and did lots of conversions and had several propane powered vehicles, so I believe he know a bunch about propane, not sure about this tho.
Several people have said propane burns hotter, but then I know it also draws heat to itself as it turns to gas. Can anyone describe this to me?

[bumpstart]

you are burning propane or propane/butane VAPOUR. by which it means there is little to none advantage in latent heat exchange with the inlet air
in fact there is some minor volume displacement of the inlet air due to the expansion ratio of the LPG fuel when introduced into the inlet airstream

it uses coolant to boil the liquid gas ( else the fittings freeze ) as it drops the liquid tank pressure to just below ambient
( for impco mixers )


however the gas can burn hotter into the exhaust stroke
( compared in the case of the old school plunker petrol vehicle )
because LPG vapour does not provide a cooling effect when you run it overly rich
and ( at less than full load ) also likes timing to help aid its burn speed else some of the energy misses the window it can apply to the crank power stroke and is lost to the exhaust



tuning a petrol engine to provide exhaust temp control and boundary layer suppression means running rich and far from a perfect equivalence ratio under load

and so the fact they tune to 11:1 under boost and 13.:1 at ambient
while you run 13:1 in boost and 14.5:1 at ambient
( and 15.5 cruise and idle if using the feedback controller )
throws all energy/ pound density comparisons ( that don't initially look good on paper ) into LPG's favour

LPG will ( mostly ) like more timing to speed up the burn rate and get more of the burn into the powerstroke

else.. retarded or rich. more energy goes into the exhaust ( or rad )

it is that simple .
and easy to see why old mixers without feedback
and distributors with a petrol curve on dual fuel vehicles added up to seeing high exhaust and radiator temps

/ LPG also makes N0x when it runs too rich under load .
( well in piston engines anyhow. the wankel rotary is most immune to making NOx )
so another reason the feedback control stuff came about to keep the engine cruising and idling within a mixture window

in view of boost you should think about -

adjustable timing control

water injection for the power just beyond what you seek .
( as there is a point where another exhaust temp control mechanism becomes necessary )

a pre turbo upper cylinder lubricant applicator

[gearhead]

that makes more sense!
so its likely u could see higher coolant temps over petrol engines. I'll run a big v8 rad then not only because i'll be adding boost but because of the properties of propane

a pre turbo upper cylinder lubricant applicator

what is this, piston cooling nozzles?

[bumpstart]

it is a system added to older cars to supplement the lack of valve lubricant in LPG fuel .
just a bottle and a metering dripper and not unlike some water injections systems

putting it pre turbo gets rid of issues with the bottle needing to take boost pressures and makes the metering easier to setup

i dont use one on my rotary. cause it has a dedicated oil injection pump that does a similar job into the intake airstream
( mine being ECU map controlled with engine revs and load )

PS .the hotter the thermostat the car runs then the higher the flow rating you will get out of the convertor before it freezes
170 F is a normal range for older carb vehicles , however most EFI vehicles usually have 180F to 190 F thermostats

if you tee from the vehicle heater hoses it is fine to return the "spent" coolant to the bottom tank on radiator
( or back into heater return hose )
and because you have taken from the pressure side of the coolant system, and return to the point at lowest pressure , you have maximised the coolant flow through the convertor and thus get all its HP rating

[gearhead]

can't find really any info on the lubricant injection. any site u know of that sells a kit?

My father in law said with his propane vehicles if you run the coolant temp hotter than 180 degrees F, oil comes out of the propane and can gum up your mixer and evaporator. any comments on this?

[bumpstart]

i suppose that would be a nuance from the source of your particular blend. but i have been driving at 190 F for almost 10 yrs !

i dont have the filter in my lockoff solenoid anymore though when i pulled it the issue was dry rust /dust on the little magnet

the model E is designed to run flat and keep itself clean. and the model L upright .

as long as you do that any slime will pass through to the engine unnoticed. NIL issue


http://www.flashlube.com/en/products/va ... r-kit.html

[C3H8]

In Canada you can try 2 companies that may carry the Flashlube Kit or a similar item. They are National Energy Equipment or Maxquip. NEE carries Landi Renzo and Maxquip handles Prins.

As for engine temperatures. The main issue with higher temperatures is separation of the heavy ends. The less dense the vapour the more likely the heavy ends will separate and fall out collecting in the vapourizer. As mentioned the hotter the regulator the less dense the vapour is. Fortunately in Canada 80% of our propane is refined out of NG. The product is quite clean and we don't experience much in the way of contaminants unless your propane comes from an area where propane is cracked from oil. The two areas this is most likely to happen is Edmonton and Toronto. During times when the refineries are working overtime in cold weather the companies can get lazy in cleaning the scrubbers (another name for filters). During this period concentrations of oil (heavy ends) is more likely in those areas. Because of this a colder regulator is less likely to get contaminated.

For vehicles that operate within normal parameters (normal HP) there is no reason to run a cooler regulator as long as heavy ends are not a problem. Most of the manufacturers rate their regulators based on normal engine temperatures of 180F+. Lowering the temp will reduce the vapourization capability of the reg. For customers who live in an area with heavy end issues and reasonable winter temperatures a thermostat of 160 will work on older model engines. I have found that the regulators typically run 10 to 20 degrees colder then the coolant temperature as the propane vapourizes.
On newer computerized systems there is no choice. The factory temperature is required to keep the computer happy.

Keep in mind that running a colder thermostat will lower the capability of the peak HP of a reg. Choosing to run at 160 may require an additional regulator on modified higher HP engines. An example is an engine designed to run 325 or 350 HP. One model E could be used as long as WOT is used for short periods running the engine at 180 to 195 F. Lowering the temperature to 160 might end up with the reg freezing up quicker at WOT requiring the addition of an additional reg to handle WOT loads.

Just my thoughts

[gearhead]

Cool! That makes perfect sense! I picked up to model e condensers, this way I know ill have enough fuel flow no matter thaw temp or even if I'm wide open for extended periods.
Thanks for the Canadian sites, not much general info for the fuel lubricant.

[TurboDario]

For what it's worth, I run a 195* thermostat in my stuff, I figure the extra heat helps with vaporization when pushing the limits of the converter.

[gearhead]

So, I've been gathering parts fairly rapidly and i'm at a crossroad.
My friend has been telling me to get a megasquirt ecu and control the ignition system, which I think is a great idea instead of using primitive distributor and playing with weights and springs....not fun
so now i'm going well, if I already have ms, why not go fuel fuel injection....and I saw the keihin injectors for lpg where mentioned already.
IF I did this, i'm just wondering how those injectors mount and how many do I need, two per cylinder?
How much would that all cost? and do I need a different evaporation/condenser?
thanks guys!

[storm]

The Keihin injectors are usually used in conjunction with parts from manufacturers such as Prins and I think even BRC. Prins has a regulator suited to these injectors. The injectors are colour coded for output so you choose the injector to suit your engine. If you have a V8 and want 400 HP you run 8 of the 50 HP injectors if you want 300 HP you run injectors capable of flowing 37.5 HP. There are also different regulators suited to different engine configurations (straight or V block).

[bumpstart]

the reg is very different and much smaller than the mixer reg.. the latest are all milled metal and look remarkably like a large petrol aftermarket fuel reg. but with in/ out coolant hoses ( and a wiring pigtail ) and two outlets for v bank/staged bank etc

it does not need to reduce the pressure as drastically and does not thus need the same internal heat exchange surface
they have inbuilt pressure and temp senders which feed specialised LPG software which will alter the fuel map table with modifiers that are intended to re-correct for fuel density fluctuation

READ; special LPG tuning software is necessary if you want exacting control of the fuel mixtures as with LPG vapour injection the temperature and delivery pressure is very much part of the equation

biggest keihin injectors dont give much more than 50 hp each which for most may require you to get your head around a "staged " injector setup and the profire system i have seen has all this in the software and the ability to drive 16 injectors ( expanded to 16 drivers ) and yet only a wastespark v8 ( 4 driver ) ignition. tells its own story

and the ones i have seen can be direct replacement for ev1 type injectors in standard fuel rails
( that have the factory reg removed and the return capped )

they also fit in a gang bracket, linked with fuel hose and you tap the manifold where they line up and insert a threaded bung and the injectors plug in . and you make a bracket to hold down the gang

that is the new reg setup and a gang of keihins on a supra the reg is 450 hp rated

this is the injectors in standard rx7 fuel rails which have the return capped
in the foreground is the original black regulator , also 450 hp rated, but a bit bigger than the shiny one

this is one of the backscreen maps in the profire lpg or lpg/petrol software showing there is inputs to ascertain the fuel density . be sure the mega squirt has the aux in spare and the software to modify the fuel maps thus


im in two minds myself
as this profire rx7 is much neater to look at. but still ( without extra injectors and quality tuning effort ) fails to match the performance of my 225 mixer setup on my personal rx7
( albeit with a haltech driving the ignition/ boost control/ fuel safety cutout/ power valve )
the mixer system while a bit messier and bulkier only really suffers from pressure loss through the mixer
conceding that most turbo intercoolers on street cars need to be compact and are tube fin and also offer significant inlet restrictions
i opted to a larger bar/plate cooler to offset my losses

bear in mind in the next pic.. this is my rx7 at idle
. notorious for requiring a rich idle mix to keep a stable idle
.. its a hot day and i havent been holding back as you can see that in the coolant temps
this is also a 225 mixer cdp-02 system in action on the "three wind" tuning principle i have outlined in another post
( using an electronically switched power valve and pill as the fine tune for WOT mixture )

[gearhead]

I looked into the price of injectors....I think ill start with mixer and take it from there. I can always change it later, super cool tho.

anyway, heres a pic of my car that will be getting the propane and engine swap