I am running a new motor with heads cam and i was wondering what the stock fuel system can handle. I have 243 heads, 234/242 .600;.650 lift and 112 LSA, i also have injectors out of an 04 cobra. I also have a built bottom end for nitrous but i don't have a fuel system yet and i want to spray like 75 shot or a 100 shot, and i was wondering if i would be okay? I really don't want to run out of fuel. Would a fuel pressure saftey switch be the best way to go to make sure nothing bad goes wrong?


Ryan

 

well I can say that I am running an extreme head and cam package on my 346, and I use upgraded rails, 42# injectors, and walbro...I am also planning on throwing a 100-125 shot on the car, and at that point will consider upgrading either injectors, or an additional fuel pump (not that is it neccesarily needed, but may benefit more power in the future)
You could also consider a KB BAP, but I feel that a BAP is ajust a "bandaid" type of fueling fix...don't use bandaids with N20 unless you want problems...

I would seriously consider upgrading fuel components because the LAST thing you want to have happen is you run lean....and KABOOM...

Food for thought
Good luck

*EDIT*

As far as safety goes, a FPSS is a MUST AFAIC. I would also invest in a WOT switch or a window switch so there are no inadvertant "mess ups" on your part...

 

you may want to look into a stand alone fuel system. I have a racetronics fuel pump, 42lbs injectors, Fast rails, fuel pressure regulator and I was tuned for spray. My tuner told me that my system would only be good for a 75 shot. When we stepped up to the 100 shot it kept going lean and couldn't get it rich with tuning. When I was at the track I said screw it and jetted for a 150 shot on the nos side and jetted for a 175 shot on the fuel side and kicked the timing back another 2 degrees. It ended up leaning out and melted 3 spark plugs and burnt one valve. A FPSS or a stand alone fuel system would have prevented that from happening. If I would have only listened to my tuner instead of getting caught in the moment at the track. I lucked out but it could have been worse. Learn from my mistake. My car made 523rwhp on the 75 shot. Our fuel lines are not big enough to feed much more than 550 rwhp. At least mine couldn't. My stand alone is in and I'm a cam change away from a 9 second pass on a 150 shot

 

I have zex kit right now, i know that noids aren't that great for my goals, but at this point in time i just want to know if i would be okay on spray, but the way it sounds i am gonna say no. Probably upgrade nitrous kit for next season and hope for 10s or better on a 200 shot.

 

Spray it! I would think you would have no problem at all just watch your afr and fuel pressure and you'll be fine.

 

it seems sometimes it is a hit or miss on the fuel system in our cars. i made 513 rw on the stock pump and 42 lb injectors but it was starting to drop pressure.then i put my racetronix kit on (pump and hotwire) when i put in the 408 and 9" and it is dropping pressure also (10 lbs or so) and then some have made 600rw on these cars with no problems. i'd say with 550 rw or so you (should) be alright with a good pump.

 

I'm running a stock system with a racetronix and 30# SVO's. Car has a fine a/f on the spray. Did 430 on the motor, and about 540 with the 100 shot. I would highly reccomened an FPSS for any car on the spray.