Fueling & Injection Fuel Pumps | Injectors | Rails | Regulators | Tanks

Help with AN sizing.

Thread Tools
 
Search this Thread
 
Old Jul 31, 2017 | 03:44 PM
  #1  
jlee29's Avatar
Thread Starter
On The Tree
iTrader: (5)
 
Joined: Sep 2009
Posts: 120
Likes: 0
From: California
Default Help with AN sizing.

Hey guys I'm putting a new fuel setup in my car and I need help with the sizing. I want to run

10-AN feed
8-AN return
Twin Walbro 450's in tank

My question is for the feed line do I need all of my hoses and components from the pumps to the rail to be 10-AN including the FPR? I ask bc I need to buy a FPR and a lot of them are 6 or 8-AN. Would it be redundant to run a 6 or 8-AN FPR and line to the rail (3' of line)?
I feel like the obvious answer is yes 10-AN all of the way, but I already have some 6 AN lines and was curious if I could use them.
Thanks
Reply
Old Aug 1, 2017 | 12:06 AM
  #2  
G Atsma's Avatar
TECH Senior Member
5 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2016
Posts: 22,291
Likes: 3,616
From: Central Cal.
Default

Depends on the actual need for fuel your engine has. How much HP are you pulling? If it's the engine mentioned at the bottom of your post, 8-AN would likely get the job done. BUT, if you have done a LOT more to the engine, then 10- is your number.
Reply
Old Aug 1, 2017 | 06:57 AM
  #3  
HoodRatHotRod's Avatar
Teching In
5 Year Member
 
Joined: Jul 2017
Posts: 10
Likes: 0
From: Bowling Green, KY
Default

It depends on how much horsepower you need to support, but ideally if you're plumbing it primarily with -10 I would want the whole feed side to be -10 or larger. -8 is typically good up to about 750hp on gas, though.
Reply
Old Aug 1, 2017 | 08:41 AM
  #4  
JoeNova's Avatar
Restricted User
 
Joined: Mar 2014
Posts: 7,192
Likes: 109
From: Ohio
Default

-10 is what they use to feed methanol to 4000 HP pro mods.

-6 line is more than enough for any N/A LS setup.
Reply
Old Aug 1, 2017 | 12:02 PM
  #5  
jlee29's Avatar
Thread Starter
On The Tree
iTrader: (5)
 
Joined: Sep 2009
Posts: 120
Likes: 0
From: California
Default

The car is a 6.2L with a D1SC so as it is it should be in the upper 600-700rwhp on E-85, so that's the reasoning behind running a massive feed line.

I think the best option is to get a 10 AN FPR and run 10 AN right up to the rail. I just feel like I rarely see a large 10 AN line between the FPR and the rail even on higher hp cars.
Reply
Old Aug 1, 2017 | 12:12 PM
  #6  
JoeNova's Avatar
Restricted User
 
Joined: Mar 2014
Posts: 7,192
Likes: 109
From: Ohio
Default

The highest I've seen out of -6 on gasoline is 1528 HP.

Carbs need large fuel lines because of less line pressure, so going by any rule of thumb that a carb guy has tried to give you is completely irrelevant.

You see lots of people running -10 because they are in the same boat you are and don't know what to run, so they just run a huge fuel line.
Reply
Old Aug 1, 2017 | 02:03 PM
  #7  
HoodRatHotRod's Avatar
Teching In
5 Year Member
 
Joined: Jul 2017
Posts: 10
Likes: 0
From: Bowling Green, KY
Default

Originally Posted by JoeNova
The highest I've seen out of -6 on gasoline is 1528 HP.

Carbs need large fuel lines because of less line pressure, so going by any rule of thumb that a carb guy has tried to give you is completely irrelevant.

You see lots of people running -10 because they are in the same boat you are and don't know what to run, so they just run a huge fuel line.
You've seen a car make 1500hp with -6 fuel lines?
Reply
Old Aug 1, 2017 | 02:23 PM
  #8  
JoeNova's Avatar
Restricted User
 
Joined: Mar 2014
Posts: 7,192
Likes: 109
From: Ohio
Default

BMW I6 on an engine dyno, yes.

Its amazing what enough fuel pressure will do.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Aug 1, 2017 | 02:31 PM
  #9  
RedRocketZ28's Avatar
9 Second Club
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (19)
 
Joined: Jan 2005
Posts: 2,106
Likes: 4
From: Madrid, IA
Default

I run -8 feed and -6 return. More than enough for me on E85 and I make more power than what you're wanting to make.
Reply
Old Aug 1, 2017 | 11:22 PM
  #10  
jlee29's Avatar
Thread Starter
On The Tree
iTrader: (5)
 
Joined: Sep 2009
Posts: 120
Likes: 0
From: California
Default

Okay cool. Thanks everyone
Reply
Old Aug 10, 2017 | 08:41 AM
  #11  
prokaw875's Avatar
Teching In
 
Joined: Aug 2016
Posts: 34
Likes: 0
From: Hartford, Connecticut
Default

Hey man, so I was in a similar situation but with a big Weldon external pump. I have 10 feed and 8 return. Reason I went this size is because I got a weldon T2040 regulator which has 10AN feeds and 8AN Return. I don't like the idea of bottlenecks anywhere. I believe if you don't want to spend $250 or $300 on a weldon A2040 or Teflon (methanol safe) T2040 then aeromotive I THINK has a 10/8 sized regulator. If not then just get a 8an/6an regulator and get adapter fittings 8an orb to 10AN male and 6an orb to 8AN male. Whatever you do I would try to stick to 10AN feed and 8AN return that way you will never have limitations
Reply
Old Aug 10, 2017 | 07:04 PM
  #12  
jlee29's Avatar
Thread Starter
On The Tree
iTrader: (5)
 
Joined: Sep 2009
Posts: 120
Likes: 0
From: California
Default

Thank you! I've decided to run 10 all of the way. I just got a 10 AN FPR so I'm all set. Like you said I don't want any limitations in the future.
Reply
Old Aug 10, 2017 | 11:11 PM
  #13  
Dian's Avatar
TECH Apprentice
5 Year Member
 
Joined: Nov 2016
Posts: 371
Likes: 18
From: switzerland
Default

is that a returnless setup?
Reply




All times are GMT -5. The time now is 07:18 AM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE