propane dual fuel ?

[gonefishin]

ok so i am thinking about going dual fuel on the blazer and i am wondering about the mixer size i have a semi built 355 that sees 6000 rpm on a regular basis and i don't know if the impco 425 is big enough??? i am running a 770 carb and want something that flows at least that much so i am not choking my engine. any suggestions??

and i found a dual fuel kit and i dont know enough about it to know if i can make it work with a bigger mixer and i need some help please here is what i found impco model L and 300a dual fuel kit can i make this work without choking my engine???

i saw someting about a 450 when i was searching needing different things to make it work over the 425 is that correct and would the 425 be a direct replacement into this kit?

thanks guys

 

[80' 427]

The 425 is like 450 cfm. It will cut down on you ability to rev a bit. The dual fuel like you have posted is actually rated at 300 cfm and will restrict the airflow even when you are on gas. The choices for larger cfm are some large industral carbs that are hard to fit or running 2 425s. The 425s are usually used with a model E and are made to run only on lpg (not typically dual fuel). I have a 425 that I run on my 454 and I did loose some horsepower but the fuel cost savings and ability to run the engine upside down are the ups for me. Honestly my engine will still spin 5500 or better for wheel speed. One of the guys I talk to alot told me that if you want both you need to run a 300a and just remove it when you want more power (comes off easy).

 

[gonefishin]

Yea I don't really wanna have to take it on and off I go from steep hill climbs to waste deep mud in a matter of minutes so that won't work to well.

Has anyone used a impco 600? It flows 900 cfm that would be perfect for me expecially after my 383 build

 

[80' 427]

That requires a special adapter. I promise mine never has a power problem in the mud

 

[gonefishin]

What I am worried about is it restricting the carb when I am running on gas I have read that it can restrict it to the point that the carb starts running rich???

My cam makes power about 5200 rpm so I am pretty sure that would be enough but I am not so sure wen I do my hot 383 buil in the next year or so

When I am running propane power is not that important but I do enjoy hot rodding it around on the street a little too

 

[80' 427]

What I am worried about is it restricting the carb when I am running on gas I have read that it can restrict it to the point that the carb starts running rich???

My cam makes power about 5200 rpm so I am pretty sure that would be enough but I am not so sure wen I do my hot 383 buil in the next year or so

When I am running propane power is not that important but I do enjoy hot rodding it around on the street a little too

I understand. My cam is super small (done at 3950). It is just hard to use that big carb in a dual fuel application because of the restriction of the hat. The 300 has a hate that is held open with a lever when you are on gas. There are some good sites with information. I used them alot when I was turboing my truck on lpg. Rasco? Is one, can't remember right now. There is alot of hot engines. Otherwise I would consider TBI.