What size s.s fuel line?

[pitbull419]

Just like it says what sixe s.s fuel line should I run for a gt40r and 1600cc injectors?
Would 10an be over kill?Should I just go 8an?
I plan on running an external fuel pump and fuel cooler.
Yes I will be running all the supporting mods.
Also if you have a link to installing an external pump the correct way please post it.
Thanks

 

[project_tsi]

-8 will be plenty for a GT40.

 

[pitbull419]

Thanks-project tsi
Any ideas where to get some good s.s line?
Summit has some decent prices.Is there a better place?

 

[project_tsi]

Other than my local supplier, summit is a really good place to get it. And your in Ohio and I believe summit has a warehouse in Ohio so you are next day delivery. I prefer to use Aeroquip, or Earls hosing.

 

[turbosax2]

http://www.anplumbing.com/shop/index.php?

 

[dalatinromeo]

-8 will be plenty for a GT40.

Not to take over your thread or anything, but since the topic of fuel lines are being discussed I think this is a good time to ask. Should your feed lines be smaller than your return lines or should they be the same size? I've heard both opinions, I just want to get the general consesus.

Like should you have -8 feed lines and -6 return, or would -6 feed and return lines be good enough??

 

[blcknspo0ln]

Not to take over your thread or anything, but since the topic of fuel lines are being discussed I think this is a good time to ask. Should your feed lines be smaller than your return lines or should they be the same size? I've heard both opinions, I just want to get the general consesus.

Like should you have -8 feed lines and -6 return, or would -6 feed and return lines be good enough??

That's kind of like asking if a 3" downpipe + 2.5" catback is as good as a 3" turboback.

remember, a fluid system is only as good as its smallest part. I would do -8 or -6 for both sides, not one and another.

 

[dalatinromeo]

That's kind of like asking if a 3" downpipe + 2.5" catback is as good as a 3" turboback.

remember, a fluid system is only as good as its smallest part. I would do -8 or -6 for both sides, not one and another.

. See I was arguing with my friend about that. He was like he has -8 feed lines and -6 return lines. I was like that doesn't make sense. You should have got them all the same size all around. And his other 3 friends were saying yeah his set-up was a better than a -8 -6 all around. So I just wanted to see what ya said.

But good example, I didn't think about that.

 

[AuntiesTSI]

I myself am am running 8 feed and 6 return. It's the same setup on 2 of my buddies cars and they both put down over 500hp with no problems, which is what I am going for, and this was on only a 255 with a rewire kit.

 

[blcknspo0ln]

Well, i don't think anyone here is argueing if the setup works, just questioning if the 8/6 combo is as effective or more effective than a 8/8 or 6/6 combo.

 

[dalatinromeo]

Thats what I'm trying to ask which is more effective.

 

[snox135]

Comparing the downpipe and catback to the fuel lines are not the same. The engine is using some of the fuel so the return line has less going through it. The -8/-6 combo works great with no issues. A -6 line can flow enough to support 1000cc injectors. Unless you are using a huge fuel pump(s) the -6 return line is plenty. Most people using that big of fuel pump are not worried about low rpm tuning.

 

[Boosted98gsx]

does anyone make a "guaranteed to work on a 2g" -8an fuel line kit?

 

[TRBOBLU]

Not to take over your thread or anything, but since the topic of fuel lines are being discussed I think this is a good time to ask. Should your feed lines be smaller than your return lines or should they be the same size? I've heard both opinions, I just want to get the general consesus.

Like should you have -8 feed lines and -6 return, or would -6 feed and return lines be good enough??

It doesnt matter how big of a return line you run on a 2g AWD because there is a HUGE restriction in the siphon system for the saddle bag gas tank. If you ran a -6 you would be wasting money unless you bored out the siphon or removed it altogether(and put a fuel pump on the driver side to feed fuel back over). Believe it or not, the stock return line will flow more fuel than could ever flow through the stock siphon system. You have probably heard of some 2g AWD guys running dual parallel pumps and cant get their base fuel pressure below like 55-60psi. They replace the return line with a larger unit and have the same problem. Turns out the little plastic siphon wont allow enough fuel through to get the base fp down to where it needs to be. Sorry for the rant, just thought that may help you out.

EDIT: Here is an interesting solution to the 2g AWD fuel return system. This is taken from another board. He couldnt get his fp below 55psi with 2 pumps in tank.

I think I have found a solution to lowering the base fuel pressure for us 2G AWD guys running lots of fuel pump . I just pulled the siphon out of the tank and was looking at it. THe hole at the end of the venturi is tiny (around 5/64"). So I figured it could be opened up a little and still produce enough vac to pull the fuel from the drivers side of the tank. I opened it up in small increments checking the vacume each time.

Since I don't have a accurate enough vac gauge I hooked the siphon up to my aircompressor. Using 40 PSI of air pressure I timed how long it would take the vac port to drain a container of water. Opening the hole up to 1/8" only increaded the time buy about 20%. 1/8" is probably the best size to go with and I should have stoped there, however i went up to 5/32" and that drastically reduced the amount of vac produced by the venturi. It doubled the time to drain the water. However I installed the siphon back into the fuel pump assembly and put it back in the car. It is still producing vac and pulling fuel from the drivers side.

With the opened up siphon I am able to turn the fuel pressure down to 30PSI with the car running.

So the fuel lines are not the problem in lowering the fuel pressure, and upgrading them in not necessary.

 

[TRBOBLU]

Just like it says what sixe s.s fuel line should I run for a gt40r and 1600cc injectors?
Would 10an be over kill?Should I just go 8an?
I plan on running an external fuel pump and fuel cooler.
Yes I will be running all the supporting mods.
Also if you have a link to installing an external pump the correct way please post it.
Thanks

-8 is a good setup for that turbo. You could even run E85 and a couple of fuel pumps and should have no problems with it being a restriction. Now if you wanted to make 750+whp on E85 then maybe you should think about -10. But other than that -8 is big enough for 98.576% of DSM'ers(and its what I run )

 

[AuntiesTSI]

By siphon you mean the tube directly onto the top of the fuel pump assembly where the line ends???

 

[TRBOBLU]

By siphon you mean the tube directly onto the top of the fuel pump assembly where the line ends???

No. The siphon assembly is the white plastic piece with the rubber hose connected to it. Heres a pic to show you what I mean.

You must be logged in to view this image or video.

 

[dalatinromeo]

-8 is a good setup for that turbo. You could even run E85 and a couple of fuel pumps and should have no problems with it being a restriction. Now if you wanted to make 750+whp on E85 then maybe you should think about -10. But other than that -8 is big enough for 98.576% of DSM'ers(and its what I run )

Just so I'm understanding right, you are saying that a -8 feed line and your return line is more than enough for 98% of DSMer's

 

[TRBOBLU]

Just so I'm understanding right, you are saying that a -8 feed line and your return line is more than enough for 98% of DSMer's

Im saying the -8 feed is enough for most DSMers. Upgrading the return line on a 2g AWD is pointless unless you address the real problem with the return system(the siphon like previously mentioned). I run dual intank fuel pumps and a -8 feed line and the stock return line with the stock unbored siphon. One pump runs continously and the other kicks on at 15psi. I have the second pump kick on at 15psi so I dont overrun my stock return system.

 

[DirtyBirdRacing]

Comparing the downpipe and catback to the fuel lines are not the same. The engine is using some of the fuel so the return line has less going through it. The -8/-6 combo works great with no issues. A -6 line can flow enough to support 1000cc injectors. Unless you are using a huge fuel pump(s) the -6 return line is plenty.

I agree.

Bill

 

[AuntiesTSI]

So not having the siphon would help. Like this??

http://i70.photobucket.com/albums/i92/imannja/DSCN2208.jpg

 

[Boosted98gsx]

Comparing the downpipe and catback to the fuel lines are not the same. The engine is using some of the fuel so the return line has less going through it. The -8/-6 combo works great with no issues. A -6 line can flow enough to support 1000cc injectors. Unless you are using a huge fuel pump(s) the -6 return line is plenty. Most people using that big of fuel pump are not worried about low rpm tuning.

Well the exhaust in a car does radiate out a LOT of heat and cools down significantly in the time it takes to get to the back of the car, so it becomes more dense taking up less space. If you wanted to keep the velocity constant (even though it may be minuscule) you would need to taper the exhaust.

 

[dalatinromeo]

Im saying the -8 feed is enough for most DSMers. Upgrading the return line on a 2g AWD is pointless unless you address the real problem with the return system(the siphon like previously mentioned). I run dual intank fuel pumps and a -8 feed line and the stock return line with the stock unbored siphon. One pump runs continously and the other kicks on at 15psi. I have the second pump kick on at 15psi so I dont overrun my stock return system.

Oh okay thanks!!

 

[Ajax]

Little off topic but a question about fuel supply non the less. I am using -6AN for feed from an intank 255 walbro, and my stock feed line as return line, since the 1997 GS FPR was at the tank. Now the question is I just got some 1600cc injectors bc I want to run E-85. Would everything be able to keep up?

 

[Boosted98gsx]

Little off topic but a question about fuel supply non the less. I am using -6AN for feed from an intank 255 walbro, and my stock feed line as return line, since the 1997 GS FPR was at the tank. Now the question is I just got some 1600cc injectors bc I want to run E-85. Would everything be able to keep up?

How much airflow are you trying to support? Typically to fully use 1600's you'll need an external pump (bosch 044), and -8an