i have a 1994 f250 351w c6 on propane only. previous owner had dual fuel then decided to go with straight propane; removed both gas tanks. i don't know what else, if anything was removed.

i need to get this truck through emissions testing and so i am giving it new : cap, rotor, plugs, wires, air filter, and oil change.

my question is : what should the timing be set at for this engine to run on propane ? i am not even sure if it has a spout connector on this year but, if it does, should it be disconnected ?

the truck actually runs fine (except for an up-and-down idle during warm-up only) but it's due for the tune-up anyway.

 

you will get better and more in general response in the gasser section. Diesels use propane like you would use nitrous. Try the alt fuels section under gas performance I believe. Smart guys over there too!

 

ok, after reading the title of this forum more closely that makes sense . thanks.

 

usually propane powered engines timing is set a few degrees early... if you can find a local propane distributer. that sells or knows a installer. they will be able to give you the correct settings.
if you ever need to remove the heads, have them shaved or do it right ... install high compression pistons and rods... 12:1 would be a good place to set the engine up for, as propane has 105+ octane....
the higher compression will give you more power and mileage...

 

I have a 1990 f-250 with a 351w and e4od and bi-fuel propane system. There is a nameplate under the hood that calls for 10*BTDC, which is the same as stock if I remember correctly.