88blackgt

*edit* i got ya first post

either way its defintly more than 250 or 300 like some said earlier

r.barn

725hp X .82 = 595rwhp

turbostang21

if i remember correctly a 255lph is good for 450whp and that's pushing it... i'm within 50whp+/- for sure

hrd2bslw

I know for sure they can handle 500 RWHP because my cousing has stock rails, lines and a 255 fuel pump and has no problems.

I do not know about 600 RWHP though. Would I have to get bigger fuel rails and fuel line all the way back to the tank ? How much would this cost ?

BADNOTCH

I am putting down 679rwhp. I installed a aeromotive fuel system from summit and 72lb injectors. I am changing my injectors to 96lb because I was running out of fuel. If you can make 600whp, put a $1600 fuel system in your car, along with FAST, b/c when you get on the dyno and pay a tuner over a grand to tune it and run out of fuel, That sucks.

88scgt

i have heard that stock fuel rails will only hold around 500 rwhp. our drag car has stock rails twin 255 pumps and 42# injectors and we got 586rwhp. at about 6000 rpms the car starts to lean out so we are in the process of changing to larger fuel rails. so i know they can atleast hold 586

7upedition

No the stock FI and pump will not support that kinda hp, hardly half of that, niether will the stock block.

88scgt

i understand that but the original quewstion was what kind of hp will stock rails hold. i said in my post that the fuels system minus the rails have been changed. stock rails held that amount of power. and a stock block will hold more than 300 hp. there is a toss up on really how much hp stock block will hold. some say 450 or 500. we have two cars over 460 and have never had a problem. there are several things to consider when building an engine on a stock block. all internal parts should be seperatly balanced and then balanced as a unit, auto trans and no nos. all of these things will help a stock block hold more power. we have been runing our cars for over a year and only thing we have done is change oil. so stock blocks will hold the power they just need to be built right

88scgt

aim not sure on how much hp a 255 is good for but i have 460 on a 195 pump, and run rich

nitrous_bob

2 my buddies dyno over 500 on a mustang dyno, 1 at 502 and the other 518

both on stock rails.