Is my Fuel sysyem up to Par?

[BillaMustang]

Alright I'm in the process of building a 331 with AFR 185's, Vic Jr intake, Custom FTI Solid cam, 750 Demon carb etc.. And I'm shooting for very high ten's or low 11's on a bad day. But my fuel sys. consists of a 190l.p.h. EFI pump along with the stock lines and an Two Fuel regulators, The first reg. being an Aeromotive Bypass and also a Holley Blue pump reg. I have to run the two reg's because of the EFI pump runs on 40 psi so having two reg's I have the pressure set on 7 psi.

Anyway's I did a jug test today and it took One minute to pump a gallon of gas.. Is that enough?

 

[cuda66273]

I doubt it....a 10 second car needs to fill a 1 gallon jug in 20 seconds.

Do the math, you'll burn about .5 to .65 gallons on a pass in 10 seconds X 6 = 3 gallons per minute X 60 minutes = 180 gallons per hour at carb pressure of 7#'s.

It not rocket science, Hocus Pocus or opinion it's straight fact and simple math.

EFI pumps are generally high pressure low volume. you need low pressure and high volume for your modified engine.

At 1 minute per gallon you have a fuel system that's good for a 18 second 1/4 mile car......you will lean it out and you will melt a piston.

I have 3 brand new 408 stroker pistons on my bench right now all melted like Butter on hot corn bread. 140 Mallory Pump (90 GPH at 7.5 psi) Holley Blue Pump regulator (about 72 GPH) and a Fram inline filter (???maybe 50 GPH) 3/8th fuel line in a stock tank.

On the 3rd pass it went poof and the party was over, except for the track sweeping.

We did a fuel delivery test on it.....45 seconds to fill the jug.....total timing was set at 42*......Oppps....16 initial to make it idle and nobody even looked at the total.

This time he's having us build the fuel and ignition system for it.

 

[393Bird]

Here is some good information you should read.

http://www.centuryperformance.com/fuel.asp

Here is how mine is set up with a Holley Black:

Full fuel system:
http://www.qsl.net/wd4ngb/birdwork5.htm

 

[blown5.0]

the 190lph with the stock lines arent going to cut it period. and 2 regulators to make it work....heres what you need:
1. one of those efi intake #10 pickups with the #6 return(cap the return as it wont be used)
2. #10 line to a pump, min 140gph
3. #8 line up to regulator set around 8-10 psi
4. Dual #6 lines to the carb

 

[BillaMustang]

I doubt it....a 10 second car needs to fill a 1 gallon jug in 20 seconds.

Do the math, you'll burn about .5 to .65 gallons on a pass in 10 seconds X 6 = 3 gallons per minute X 60 minutes = 180 gallons per hour at carb pressure of 7#'s.

It not rocket science, Hocus Pocus or opinion it's straight fact and simple math.

EFI pumps are generally high pressure low volume. you need low pressure and high volume for your modified engine.

At 1 minute per gallon you have a fuel system that's good for a 18 second 1/4 mile car......you will lean it out and you will melt a piston.

I have 3 brand new 408 stroker pistons on my bench right now all melted like Butter on hot corn bread. 140 Mallory Pump (90 GPH at 7.5 psi) Holley Blue Pump regulator (about 72 GPH) and a Fram inline filter (???maybe 50 GPH) 3/8th fuel line in a stock tank.

On the 3rd pass it went poof and the party was over, except for the track sweeping.

We did a fuel delivery test on it.....45 seconds to fill the jug.....total timing was set at 42*......Oppps....16 initial to make it idle and nobody even looked at the total.

This time he's having us build the fuel and ignition system for it.

Well I went a 12.12 @112 two weeks ago And I dont have any fuel starvation problems. So since my fuel system is good enough for only a 18 second car then how Am I running low 12's with no problems?

But yeah granted this fuel system would not handle the 331.. Where as my motor now is very mild and the race weight is around 2900 to 3000 lbs.

 

[331 cobra]

One gallon of gas weighs about 6 lbs, and he was pumping 1 gallon per minute. That's 360 lb/hour. If I remember my dyno math, it takes about 1/2 lb/hour to make 1 hp if you are not really rich. I think he has enough for 720 hp. I wouldn't run a 720 hp engine on that, but 400 should be fine. 400 hp should get him well in to the 11's if he's got traction.

I would get a pressure switch for your fuel, so if you do run out of volume, it will kill you ignition. Now if you ever see that switch trip, you know you have a problem without the melted pistons.

 

[blown5.0]

remember the old fill a can trick isnt very accurate as the flow rate is under no pressure, put it under 7 or 8 psi and its probably less, under efi 40psi its probably alot worse.

besides the worst part about the above fuel system is the stock 5/16" fuel line, let alone the recirc stock fuel system suppling a low pressure carb regulator.