What size of Fuel Pump?

[HoofnIt]

This summer I am going to put in a new motor. I will probably go with the FRPP 345hp crate motor but am also considering a 327 stroker w/AFR 165s. Here is my combo so far; Cobra intake, 24lb injectors, 80mm Pro M mass air meter and ceramic shorty headers w/full exhaust. Will the 190lph pump be OK? Would the 255lph be overkill and cause damage? I am trying to get all of the parts now before I order the motor. Thanks for any input.

 

[stunner6910]

190lph should be fine.

 

[GTJake]

255lph Walbro will be fine. It's only $100 anyways. I would get some 185's for that 327...JMO. Also, 30# injectors and a better intake.

Jake

 

[HoofnIt]

255lph Walbro will be fine. It's only $100 anyways. I would get some 185's for that 327...JMO. Also, 30# injectors and a better intake.

Jake

I need the car to pass emissions so the 185s are not an option. I also forgot to mention that the Cobra lower intake will be ported by TMOSS next month. I want the car to remain streetable and reliable. My goal is to have close to 350hp at the flywheel.

Why are you recommending 30 over the 24s injectors?

 

[GTJake]

185's are made in both emissions legal and non-emissions legal versions. I think the 185's would be a better choice with the increase in cubes. I'm reccomending the 30# just because of the greater displacement. Unless you already have the Cobra intake, I would recommend getting a Performer and having Tom port match it to the 185's for you. He's doing my Performer this spring and has done them before. JMO.

Jake

 

[red94fiveo]

Having a 255 lph will not cause any damage cause its 'too big' the unused fuel will just go back in the return line. Its only 100 bucks, I'd probably pick one up, especially if you're considering a stroker.

 

[HoofnIt]

I wasn't aware of the 185s being emission legal. I already have the Cobra intake and purchased it because at the time I was strongly leaning towards the FRPP crate motor and thought it would match well with the GT40X heads. Are you saying the 24lb injectors will not support 350 hp?

 

[Pstatic]

here is an equation to calculate what HP a set of injectors will make safely.

HP= ((lb/hr of the injectors)(8 or the number of cylenders)(.85 inj duty cycle)/(.5 or Brare specific fuel consumption))

Now the way you use it is by plugging in the injector size a the X value.

HP= ((x)(8)(.85)/(.5))
#24= 326.4 engine HP
#30= 408.0 engine HP
So according to this your 350+hp crate motor needs larger than 24# injectors, or injectors with higher than stock fuel pressure (making them function effectively as larger injectors).