C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

fuel line SIZE

Thread Tools
 
Search this Thread
 
Old May 1, 2003 | 05:29 PM
  #1  
Ramanstud's Avatar
Ramanstud
Thread Starter
Melting Slicks
 
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
Default fuel line SIZE

Are the stock L98 fuel lines (undercarrage) 7/16" & 3/8" return? that's what I measured as the outer diameter, but apparently I need the inner diameter? I'm trying to order some braded hose adapters and the salesreps @ summit don't have a friggin clue. Basically if I don't know the answer already, they can't help me out.

So what do I need to know to get the right fittings?

Edit: my best guess is -6 AN for the main, and -4 AN return line. these are stock lines for an `84 but should be the same as later L98s?


[Modified by Ramanstud, 10:31 PM 5/1/2003]
Reply
Old May 1, 2003 | 05:46 PM
  #2  
LD85's Avatar
LD85
Race Director
25 Year Member
 
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Default Re: fuel line SIZE (Ramanstud)

Update:
I got those Earl's parts in from Summit today. They were right on the money.

Earl's #9894DBJ (16mm)
Earl's #9894DBH (14mm)

They are made of aluminum (blue anodized) with a -6 AN nipple on one side and a female Saginaw on the other. This way if you're running a Stealthram or Miniram you can use the stock L98 fuel lines to plumb the custom fuel rails.
http://forums.corvetteforum.com/zerothread?id=543159
Reply
Old May 1, 2003 | 05:56 PM
  #3  
Ramanstud's Avatar
Ramanstud
Thread Starter
Melting Slicks
 
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
Default Re: fuel line SIZE (ld85)

thanks Ld85- I saw the thread but didn't register the line size.

but I also need tube sleeves and collars to go over the regular fuel line, which again have the outer dimensions listed above. they're different diameters, so what sizes do i get? 3/8" is -6 AN, but they don't make a -7 AN.... (7/16")?

what am I missing?
Reply
Old May 1, 2003 | 06:26 PM
  #4  
LD85's Avatar
LD85
Race Director
25 Year Member
 
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Default Re: fuel line SIZE (Ramanstud)

Actually what they do is give you a 14MM-female thread thats fits to your exsisting fuel return line but steps up to a 3/8" hose and fitting that goes to your fuel rail.

And a 16 MM-female thread that goes to a 3/8 tube.

So the fuel feed line feeds from the 3/8 line to the fuel rail and the return line feeds back thru the fuel rail then thru a 3/8 line to a 3/8 fitting that steps down to the 14-mm reducer fitting that feeds the 5/16 return line.

Are you thoroughly confused now :crazy: :crazy:

Left pic is large 16 MM Ssaginaw thread, right is 14MM Saginaw thread and the MALE threads are the same size.



This pic is the saginaw thread and the fitting that connects to the 3/8 fuel line




[Modified by ld85, 6:43 PM 5/1/2003]
Reply
Old May 2, 2003 | 01:50 AM
  #5  
Aggravated4life's Avatar
Aggravated4life
Race Director
10 Year Member
 
Joined: Aug 2000
Posts: 14,130
Likes: 7
Cruise-In II Veteran
Default Re: fuel line SIZE (Ramanstud)

Just for reference,only first few years L98 got two difference sizes for lines.
Im not sure what year,maybe 88 or 89,both feed and return became 3/8.
Before that one was 3/8 and the other smaller.A -6 AN fitted sized line would replace the 3/8 size.
Btw,which lines are you replacing,the gas tank to the filter area or from the filter area to the front?I replaced the lines from the tank to the filter area with braided lines and if I could do it again,Id shop around and find soomeone to make me a steel set of 86 L98 lines off a copy of an old bended already set.
Theres not much room under the car to secure them.
Let me know if you need any info...been there done that.
:)
Reply
Old May 2, 2003 | 12:38 PM
  #6  
Ramanstud's Avatar
Ramanstud
Thread Starter
Melting Slicks
 
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
Default Re: fuel line SIZE (Bill's86Coupe)

thanks for the reply Bill, Larry was kind enough to walk me through it so all problems are solved. But for what it's worth, I'm using the existing hard lines through the undercarrage and just replacing what would be the front fuel lines at the lower front of the engine (the two u-turn rubber hoses). Basically this is a somewhat custom conversion I'm doing, so I need the flexibility of braided to make my life easier. I *could* deal without the cost though.... :D

I'm using -6 AN hose for both lines, but I'm going to use a -5 to -6 AN adapter to connect the return braided line to the smaller stock return line and hopefully call it a day.

:thumbs:
Reply
Old May 2, 2003 | 02:36 PM
  #7  
LD85's Avatar
LD85
Race Director
25 Year Member
 
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Default Re: fuel line SIZE (Ramanstud)

If you are going from a rubber hose to a hose fitting this type of fitting to go into your hose then add thread coupler in the middle

Reply
Old May 2, 2003 | 09:30 PM
  #8  
Ramanstud's Avatar
Ramanstud
Thread Starter
Melting Slicks
 
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
Default Re: fuel line SIZE (ld85)

Thanks larry, that's what I was envisioning. But as it turns out, I braved I-37 traffic (on a Friday no less) and poor weather to drive up to Gasoline Alley and Earl's.

They hooked me up with some compression fittings (5/16" & 3/8") for the stock fuel tubes (both sizes) that had male -6 AN ends. Add two 14 & 16mm saginaw fittings and 4 braided hose ends plus 6 ft of braided hose, and I am all set.

All for a measley $128. :lolg: If this stuff wasn't going to outlast the engine, I might have an issue spending so much. But it will look cool and this qualifies as "doing it right."

:cheers:

Edit: this really turned out to be pretty simple- no collars, tube sleeves or $6 adapters. I ought to take a picture of the setup and have someone post it for future reference. Perhaps even a little blurb in the Tech section?



[Modified by Ramanstud, 2:32 AM 5/3/2003]
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-1

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-2

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-3

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-4

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-5

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-6

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-7

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-8

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-9

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
Old May 2, 2003 | 09:56 PM
  #9  
LD85's Avatar
LD85
Race Director
25 Year Member
 
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Default Re: fuel line SIZE (Ramanstud)

Congrats, Earls is awsome but dang, they are not cheap.

Send me pics and I will give you links so you can post them using my site.
Reply

Get notified of new replies

To fuel line SIZE





All times are GMT -4. The time now is 08:52 PM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE