High hp fuel system...

[Redline240]

Ok i'm working on my list of the million parts i need to order in the next few months and i came across my fuel system. I've picked out a fuel cell, decided on 72lbs injectors and a custom fuel rail. My question is what size fuel lines should i go with? -8 feed, -6 return? -8, -8? While i don't plan to make it next summer my entire setup minus the turbo MUST support 550-600hp. I'm pretty sure -10 is too big. Should the return be the same size or slightly smaller? Also, can anyone recomend a good fuel pump with -8 threaded ends?

I got the summit catalog, lots of good stuff...but all the hp ratings and sizings are for V8's so i don't really know what i need for the KA...

Any input will no doubt be helpful...

On a side note this might be a good opertunity for WD and Ivan to tell us what they're planning for they're projects and side projects...i know WD got some crazy ideas, and Ivan is running strait gasoline...i'd like to run water/alky...

Redline

[240SXmotoring]

we are running -8an lines 96lbs injectors, custom fuel rail, aeromotive FPR, and Aeromotive external fuel pump with a 5gal. fuel cell.

[Redline240]

96lbs injecters, hmmm...thats close on 720cc's isn't it? Will 72's support 600hp? And how do u calculate it to know if it will support it?

Redline

[240SXmotoring]

72lbs injectors = 756cc injectors that is what i have on my 97 KA-T now...

for the company racecar, we are using 96lbs which i think is in the ball park of 1000cc injectors give or take a few...forgot the equation for them.

as for how i knew what to get...there are formulas out there on the net that will help you with this. i didnt use them, i just know for past experience..we are going for 600hp and 96lbs injectors are feasable for this.

[IvanAtSPRacing]

Here is a good rule of thumb. It takes about 1/2lb/hr to make 1HP. You can use this formula to figure out what size fuel pump you need and what size injectors you need. basically figure out your crank HP and then cut it in half to figure how many lbs/hr your pump needs to support. For injectors, devide that number by the number of injectors your running to figure out what size injector you need in lb/hr.

-6 line will be ok for the HP level your looking for. To be on the safe side, you could run -8 feed and -6 return. Ultimate pimpness would be dual walboro 255L HP pumps with two -6 feed lines feeding both ends of the rail to a center return. This setup would be fairly inexpensive and would provide enough fuel for about 1000 crank HP. For injectors, you will need 95lb/hr injectors to maintain and acceptable duty cycle and make 600whp.

I am waiting for my fuel pump to come in still. I am going to give the BG King Sumo a try. Supposed to be quiet, ok for constant use (not just drag race) and flow 1000 lbs / hr. If this doesnt fair well, I will go with the trusted Weldon (we just made 1248 WHP high stall AT Supra tonight with the Weldon) I will be running -10 feed (maybe split into two -8 and dual feed the rail with center return) and -6 return line. I have a Triangle Engineering 10gal cell with fuel level sender because I am racing in a street class and the car will still see some street use. I will be running 160lb/hr injectors

[Redline240]

Any issues with running 96lbs injectors at lower boost levels...say i ran 600 at the track but only wanted to run 300 on the way home, are they too big or anything or am thinking about it the wrong way?

[:: orion ::]

Your idle will suck, that's all.

Peak-and-hold, low impedence injectors have a hard time spraying the little amount of fuel required to idle.

50lbs do OK...it's starts to get bad with 72lb'ers...then it's nasty with 96lb'ers. You'll need a high idle for sure...

- Brian

[Redline240]

-6 line will be ok for the HP level your looking for. To be on the safe side, you could run -8 feed and -6 return. Ultimate pimpness would be dual walboro 255L HP pumps with two -6 feed lines feeding both ends of the rail to a center return.

Well i'm all about the pimpness, and i got one walbro 255lph inline kicking around now. I like your idea of feeding both sides of the of the fuel rail. Since my goal for the spring is a "mild"(lol) 350rwhp, the walbro i got now should do fine. But doubling up the pumps after would be simple enough, so if i ran a -8 to the pump and then split it to two -6 lines that'd work ok right?

Ok, few basic/specfic fuel system quesitons...probaly not the only one that don't know...

1. Does it matter how far the pump is from the cell?2. Does it matter how far the filter(s) are from the pump? Fuel rail?3. I assume the FPR would go at the end of the rail on the return, does it matter if its not right at the end but say 2ft further.(with center rail return i'd wanna mount it on the firewall)4. What is the desired ID of the fuel rail?5. Ivan...can i get the EMS for half price? lol...worth a shot!

Redline

[Boost_Veteran]

Your idle will suck, that's all.

Peak-and-hold, low impedence injectors have a hard time spraying the little amount of fuel required to idle.

50lbs do OK...it's starts to get bad with 72lb'ers...then it's nasty with 96lb'ers. You'll need a high idle for sure...

- Brian

ummmm how many large injector cars have you tuned, and what was it on? SAFC lol? There are plenty of hondas idling 88lb'ers and up with no problem, hell even Hondata can idle 1000cc injectors w/o problems.

the lb. to cc conversion is roughly just multiplying the lb. by 10.5 and that will get you very close.

IMO go larger (not too much) and keep a lower duty cycle, plus if you even want more power or fuel you wont have to buy new injectors again.

[IvanAtSPRacing]

Well i'm all about the pimpness, and i got one walbro 255lph inline kicking around now. I like your idea of feeding both sides of the of the fuel rail. Since my goal for the spring is a "mild"(lol) 350rwhp, the walbro i got now should do fine. But doubling up the pumps after would be simple enough, so if i ran a -8 to the pump and then split it to two -6 lines that'd work ok right?

Ok, few basic/specfic fuel system quesitons...probaly not the only one that don't know...

1. Does it matter how far the pump is from the cell?2. Does it matter how far the filter(s) are from the pump? Fuel rail?3. I assume the FPR would go at the end of the rail on the return, does it matter if its not right at the end but say 2ft further.(with center rail return i'd wanna mount it on the firewall)4. What is the desired ID of the fuel rail?5. Ivan...can i get the EMS for half price? lol...worth a shot!

Redline

1. I would say the closer the better. Unless your feeding the external with an internal.2. No, it wont matter.3. Wont matter. As long as the FPR is mounted somwhere past the last injector.4. As large as possible (whithin reason) 1/2" would suffice. The PhatKA-T rails are about 5/8"5. No, but pretty close. $2816.35 is retail price. PhatKA-T.com sells it for about 65% of that price and includes a 3bar MAP and harness, IAT and harness, and weld on bung for the IAT

[Redline240]

Thanks Ivan, and i'll be calling for that and probaly lots more later this winter...gotta finish the garage first!

Redline

[USsil80]

y a fuel sell and not a sump ... a sump is legal in a lot more racing places then a sell... i have 8 feed 6 return for a 500hp setup and i would say get biger then a nismo fpr.. i have a holey unit and it wasn't that spency .... plus to keep cost down you don't need stanell bradded lines i have aeroquip lines and they wheren't that expesive.... and a paxton external pump

[IvanAtSPRacing]

Let me translate for USsil80. What he meant to say was:

"Why would you use a fuel cell and not a sump. A sump is legal for more racing sanctioning bodies then a cell... I have -8 feed and -6 return for a 500hp setup. I would recommend getting a bigger FPR than a NISMO. I have a Holley unit and it wasn't too expensive. To keep cost down, you don't need stainless braided lines, I have Aeroquip high pressure rubber lines and they weren't too expensive. I am also running a Paxton external pump."

I hope that makes things more clear.

To respond to USsil80, I would say:

A fuel cell is more safe than a sump. You cant really sump an S14 plastic tank. For my application, the cell is legal.

Rubber lines are not legal in most racing sanctioning bodies.

I have had terrible luck with Paxton, Vortech, SX, and Aeromotive external pumps.

[USsil80]

thanks there man..sorry bout that.... the s14 tank is plastic.. the s13 is metal that is y i am doing a sump... this lines are not ruber... as for the cell only in ndra nhra will not allow it import racing...

[USsil80]

plus i work at a shop soo i get everything at cost.... very nice benif when you don't get paid for your work

[TrunkMonkey]

thanks there man..sorry bout that.... the s14 tank is plastic.. the s13 is metal that is y i am doing a sump...

the s13 fuel tank is plastic.

-demetrius

[USsil80]

i took mine out and it is metal .... about the lines

Aeroquip's AQP socketless racing hose is constructed from an AQP elastomer, with a smooth inner bore for flexibility and special textile braid reinforcement for strength. What does this mean to you? No more wrenches, no more sockets, and no more scraping your knuckles trying to install new hose. It's compatible with most fuels, coolants, and oils. Plus, with a temperature range of -55 to 300 degrees F, and a maximum pressure rating of up to 250 psi, it'll handle most plumbing jobs safely and securely.Aeroquip's AQP socketless racing hose is constructed from an AQP elastomer, with a smooth inner bore for flexibility and special textile braid reinforcement for strength. What does this mean to you? No more wrenches, no more sockets, and no more scraping your knuckles trying to install new hose. It's compatible with most fuels, coolants, and oils. Plus, with a temperature range of -55 to 300 degrees F, and a maximum pressure rating of up to 250 psi, it'll handle most plumbing jobs safely and securely.

[Redline240]

thanks there man..sorry bout that.... the s14 tank is plastic.. the s13 is metal that is y i am doing a sump... this lines are not ruber... as for the cell only in ndra nhra will not allow it import racing...

Not a problem for me either...especially since there's no "import" racing here, or anywhere near here. Just fill in's and bracket...oh well, i can still be the fasted import at our track! lol...

Redline

[USsil80]

TRUE THAT