406 datr pro 1 525 lift cam forged slugs have a single feed line to the carb 3/8, looking to run nos, got a comp 140 pump and a bypass regulator, should i t into the main line befor the regulator or after it for the nos? should i run a regulator for the nos line to ? also was told i should run a return line if so should it be off of the carb line or off the nos feed line/ please help me!

 

The best is to run a dedicated fuel system for the spary so that it can be easily tuned without affecting the pressure at the carb. But your other option may be to run a y fitting and split the fule line from the mallory pump, send each line to its own regulator one for the carb and one for the spray. Then set the carb @ 7psi and set the nitrous regulator for your desired pressure and you should be ok. Also you can use a return style regulator for this application to have a more consistant pressure and also to help keep the pump cool. But you can get away with running a dead end regulator of you want.

 

Id suggest running a dedicated fuel system for the nitrous. Thats what im in the process of doing now.

 

should the return regulator be used on the carb line or the nos line?

 

If you are going to try to share a single fuel pump and run a regulator to each system you really shouldnt use a bypass style regulator for either, you will probably have starvation problems. You can use a single bypass style regulator and run both the carb and nitrous from it but you will loose some adjustability when you do this because you will have to worry about maintianing adequate fuel pressure to the carb at all times. You have many options when plumbing a fuel system and if you dont have a complete grasp of the requirements of the components that rely on this I suggest you get a professional to run it for you. Fuel will keep the engine alive it is better to go overkill then too small..

 

Ain't that the truth. I'm running -8 line from my 1gal cell to my fuel solenoid. Probably never use it, but the -8 fittings are sometimes cheaper than the -6. The -6 is more common so they stick you on the price.

 

The ideal situation would be to have a return on both lines. But no one wants to pay for 2 reg.