can anyone tell me the specific part #'s to switch over to propane or duel fuel on my truck
68 d100 6/225
thank you
jason

_________________
lp.org

Hey Jason,

I'm also interested in CNG/LPG/ and here are three links I found regarding same:

http://www.slantsix.org/forum/viewtopic ... lpg#192881

http://www.slantsix.org/forum/viewtopic ... lpg#198801

And:

http://www.impco.ws/products.htm

Lots of 411 to read up on.

_________________
~Spider
1963 Dodge D200 w/225
______________________
"The three great essentials to achieving anything worthwhile are; first, hard work, second, stick-to-it-iveness and third,
common sense."
- -- Thomas Edison

Sure... run a search on this website for Raso.

You'll find lots of information from a very knowledgeable fellow in the field of propane conversions.

Also look here:

http://rasoenterprises.com/WebSites.htm

-Mac

This might be helpful:

http://www.landirenzo.com/repository/do ... ystems.pdf

Unfortunately, LandiRenzo (and most other European) products are not available in North America. Since Canada has adopted many European standards, Canadian vehicles could potentially be outfitted with these types of systems. However, the USA requires compliance with NPFA 58 and many great products are not available to Americans. The standard conversion for older American engines are made by Impco and you can download their master catalog from Impco's Product Page. NGVINA also has Impco-like products and you can download their Streamline catalog from NGVINA's Streamline page.

Having said that, converting a slant six engine can be quite straightforward with available systems, depending upon your application. The simplest conversion is mono-fuel (straight propane) and DaddioJoe is one member who has such a system on his 71 D100. Although the Model 200 mixer is better suited to a 225 slant six than the Model 125, the 1963 Rambler LPG Conversion site gives a good explanation of the process. I have 1bbl conversion kits and 2bbl conversion kits available for slant six engines. For high performance applications, Technocarb's 4bbl carburetor is a better choice and is available in a 400 CFM model. It's a bit more expensive than the Impco stuff (once you compare them equally) but is a complete high performance, feedback system. The Australians are big fans of Technocarb's carburetors (see this topic).

Bi-fuel (or dual fuel) on carbureted engines is a bit more of a challenge because the mixer is mounted on top of or upstream of the gasoline carburetor. For some vehicles, this causes a problem with hood clearance. On trucks, this is less of a problem. Today, another challenge is that more and more of the necessary parts are becoming obsolete. For example, Impco had a Model 175A bi-fuel mixer (similar to the Model 300A) available for smaller engines. This is obsolete so another similar size bi-fuel mixer (Model 125M-10) could also work on similar small engines. The Model 175A was rated at 210 CFM @ 1.5" Hg while the Model 125 is rated at 202 CFM @ 1.5" Hg. Some custom fabrication would be involved in making the Model 125M-10 work with a 1bbl or 2bbl carburetor.

A 225 CID engine requires 249 CFM @ 4500 RPM and 85% VE. Although the Model 300A (1 & 20) is rated at 348 CFM @ 1.5" Hg, this mixer is rated for 120 CID to 400 CID engines due to its unique design. The Model 175A was typically used on 1L to 3L engines, primarily 4 cylinders. It was a difficult mixer to adjust and set up so it fell out of favour. Although the Model 125M-10 would work OK on a slant six, the Model 300A would be the better choice for dual fuel because of more readily available adapters.

Vialle also used to make venturi mixers (as opposed to air valve mixers like Impco's) in sizes suitable for slant sixes. These are still available on a used basis from time-to-time. For an idea of what these mixers look like, I have some examples on this page.

A third option for LPG conversions is to try a vapor injection system for use with aftermarket EFI controllers like MegaSquirt. Basically, I've taken Technocarb's ESIP conversion, removed the ESIP controller, and added a high current driver for the 3-ohm propane injector coils. If you're up for a science project, you'll want to give this one a try.

Since you have a truck, my suggestion would be to go to a mono-fuel system because you can carry more than enough propane to never worry about being stranded. A large tank also gives you the flexibility to always fill up at the cheapest stations. Manchester Tank and Sleegers Engineering make ASME motor fuel tanks. If you have chance, buy tanks made to CSA B51 Annex G, which is a higher standard than what NFPA 58 requires.

I didn't know. I posted it as an example of a pretty simple bi-fuel setup. The advantage of using a venturi mixer is that you don't have the change the carb in any way. There's just a valve that closes the fuel line when running on propane.

this has given me a lot to read, however several of the parts dO not seem to be avaliable to me HERE in AL.
so let me ask this way
if my engine gets up to about 230 cfm will the following work for me
impco model ca125 carb
impco model "L" vaporizer
as far as an interlock valve i am not sure what i need but i would like all of this to be vac. controled.
am i getting any closer?
thanks jason

_________________
lp.org

from what i can tell i want an open loop system if that helps you guys direct me in the right direction.
jason

_________________
lp.org

There is no problem using a mixer that is undersized for your engine. Oversized mixers are more of a problem because you could run into starting problems and poor low speed operation. The only problem you will have with an undersized mixer is that your fuel mixture will lean out above the rated flow of the mixer. Lean mixtures generally do not cause problems in gaseous fuel engines other than the loss in power.

The Model L mixer will work fine with a CA125. Many people prefer the Model E for performance and both have the same hp rating. The practical difference is the positions of the nozzles. The VFF30 fuelock is commonly used to shut the fuel off when the engine is stopped.

If you go to the Impco's latest catalog, read CARBURETION THEORY AND OPERATION (pdf page 15), you will see a diagram of an air-valve carburetor (mixer + throttle body = carburetor). The gas metering valve lifts off its seat in direct proportion to air flow. Vacuum is produced inside of the mixer, which is used to move the gas metering valve. You need a minimum flow to lift the valve off its seat and this requires about 6" WC. The valve will reach its maximum lift at about 13.8" WC and this is the mixer's rated flow. Your propane system will work best if you properly size the mixer to the engine.

Propane mixers are extremely simple devices. Unless you get an OHG X-450 (or Streamline CA475), there is no provision for load-based fuel mixture control. Open-loop gas valves start off lean and gradually become richer until you reach the rated flow of the mixer. The fuel is supplied to mixer at a constant pressure from the converter. This means that the temperature of the fuel (controlled by the temperature of the engine) affects the density of the fuel reaching the mixer. Open-loop systems always start off rich (the colder, the richer) and gradually become leaner with increasing temperature. Therefore, short trips and/or cold weather operation have a significant detrimental effect on fuel economy.

The feedback system uses a rich gas valve and the controller pulls the fuel mixture lean by varying the pressure on the top of the secondary diaphragm in the converter. Using a narrow-band O2 sensor, the feedback system maintains a stoichiometric fuel mixture. Although you can get better fuel economy with a slightly lean fuel mixture of the open-loop gas valve, you will get generally better overall fuel economy with a feedback system.

Actually, there is no reason that you could not use a feedback controller with an open-loop gas valve. Your NOx will likely be higher with a open-loop gas valve but your fuel economy will be slightly better too.

i believe this will get me started. if i am understanding this correctly i would have a vff30 lockout valve and a model L or E vaporizor going to a ca-125 carb (or into the hole i drill in the throat of my old carter 110).
sounds easy enough. now i just need to go junk yard diving for some parts i can rebuild.
thanks again, jason

_________________
lp.org

I'm not sure what you mean by drilling a hole in your old Carter 110 carburetor. If you're thinking about doing a spud-in conversion, I don't recommend it. It sounds like you're trying to do the cheapest conversion you can. The problem is that what you'll save on parts, you'll spend many times over on wasted fuel.

Also, working with gaseous fuels (LPG and CNG) can be dangerous if done incorrectly and many countries only allow licensed personnel to work on such systems. My recommendation is that you do NOT put any fuel into your new propane system until you have it professionally inspected. All propane conversions in the USA must conform to NFPA 58. Canadian conversions must conform to CSA B149.5. I highly recommend that you get copy of these regulations for yourself (and follow the advice of a professional installer) before starting. It is important that you also comply with the spirit of the regulation and not just the letter.

Hi there Frank- what wisdom can you lend unto the lowly about IMPCO's
TC2-9-C1 found on page number 282 here:
http://www.impco.ws/pdf/MASTER%20CATALOG%2010-10.pdf


the page reads:
"TURBOCHARGER PRESSURE CONTROL VALVE
The TC2 valve allows control of boost pressure without power reducing inlet or outlet restrictions. The TC2
operates in the cool environment of the air intake while allowing the turbo to operate at 100% efficiency of the
turbine up to the point of control intercept. It allows a quick throttle response and optimum horsepower
production at the desired RPM range and eliminates run away pressure and potential damage to the engine. "

unfortunately I seem to be unable to put the description into context...

Hi there. I'm just finishing up a conversion of a slant six truck to propane, a spare time/spare change type of effort. It has taken me 6 months, but in that time I have managed to find a whole lot of very good information, parts sources and techniques. Some of it even came from Franks site and forums.

I did a dedicated propane system - no gas. I have an 83gal (water, about 68 gallons of propane) or thereabouts ASME tank that I got from a big truck conversion.

I pulled the head, and shaved .165 off, which is resulting in over 10:1 compression ratio, went with stainless valves, bronze guides, hardened seats for all 12 valves - oversize valves, as well. The local muffler shop is building me a shorty type header so as to not heat the intake. I used a ca200 carb, perched atop a 2bbl throttle body and the 1.25 in adapter which matches the super six manifold.

Ignition duties are carried out by a modified Ford EDIS system using a chrysler coil an wires off a 3.3 v-6.

Timing is done by using a Megajolt timing computer, and I'm also installing a closed loop feedback system made by Impco.

I am presently waiting on the exhaust header, and have final hose routing and final electrical wiring left to do. I will install the closed loop system after I get it running.

I am using educated guess method of building a timing map for the computer, which operates from rpm and an internal MAP sensor.

If you're interested, I have found some sources for parts which are MUCH less than retail and close or less than what used equipment goes for on fleabay.

I should have this truck running in about 2 weeks, and am hoping to dyno it the middle of next month on a chassis dyno.

_________________
'81 W150 on Propane... Oversize valves, Oregon Camshaft cam, 10:5 static CR, Distributorless ignition, megajolt timing controller, PowerTrax lockers.

Regarding the Impco TC2-9-C1, there is very little information available from Impco other than what you've found in the catalog. It appears to be a device that limits boost pressure to the engine by controlling the air supply. However, this item is specific to Caterpillar and not available for purchase.

I remember reading about Impco valves for boost control. Not a good method as the turbo still spins fast, makes high boost and high heat. A wastegate for turbine/compressor speed control is far superior.

_________________
Joshua