Charlie Moua

iTrader: (3)

setup:
gsr turbo with 500-600whp e85 (goal)
walbro 400 + FIC 1000cc
aem rail & fpr



I've decided to upgrade the fuel feed line to -6an hose & fittings from M12 x 1.25 fuel pump hanger to the fuel rail. Currently my return line is -6an hose (about 2ft) then connected to stock hardline.


Q:
Is there any benefit by upgrading from stock return line (-5an hardline) to -6an hose all the way back to the tank? if so what is the benefit?


Since the return isn't pressureized, I don't forsee the stock -5an return line being any issue.
I'm curious to see what other peoples thoughts are on this.

Muckman

iTrader: (2)

No. The only reason youd need a larger return is if you were pumping and bypassing way more fuel than you're injecting. In that case you wouldnt be able to lower fuel pressure. But thats an extreme and rare scnerio.

The only reason I upgraded mine was because I needed threaded hose ends on both ends.

Charlie Moua

iTrader: (3)

......you know how it goes; if I just kept repeating ideas in my head, I'll eventually convince myself it's "right". lol

Good call, saved me $60-70 in additional lines & fittings.

m3tech95

^This. Exactly the same reason I upgraded mine

EJ1_Ex

iTrader: (1)

Charlie not sure if you'll hit 500-600whp with a single pump on e85. I ran in tank and inline at 95-98 fuel pressure to make 551.

Charlie Moua

iTrader: (3)

Thanks Cou, any advice is greatly appericated cause I'm just figuring this out myself. lol

Which brand pump would you reccomend?

EJ1_Ex

iTrader: (1)

Look at this chart from T1

scroll down

https://honda-tech.com/forums/showth...554490&page=32

LightningTeg

You can do it with that setup but you'll be pushing the pressure higher to get more out of the injectors. Im running the same pump with PTE 1000's and they are stuck open at 60psi base.

Turbo-LS

iTrader: (4)

1000cc's are not going to make 500-600whp on ethanol. Its just not possible unless you were running two bosch 044 pumps with the base cranked up to like 120 psi.

The walbro 485 will do that kind of power no problem with the right injectors. They're not really a super high pressure pump so I like to run them 50 base pressure so they dont fall off to much. Depends what turbo and how much boost you will be running on top of the base pressure.

at 600hp with the walbro 485 my id2000's with a 50 base pressure are at 60% duty cycle and it was on the right side since upgrading my fuel lines it went from 12.0 to 11.2 so it could stand to be leaned out a bit, of coarse once i rebuild it lol

My setup consists of -8 feed, -6 return, id2000's , walbro 485, stock tank, 10awg wiring to the pump from the battery and 30amp relay. Fuelab regulator, magnafuel e85 filter still has plenty of fuel left in it to hit my goal of 700+ once i go sleeved block toward the end of the year

Charlie Moua

iTrader: (3)

Cou, thanks for the link homie. I'll read though it tonight.


seeing that your nonvtec & still making decent power with the single pump, it's assuring that for now I should be okay to get into the 500whp club. lol


However, once we turn up the boost & if an inline pump is needed I have this new sx pump....kinda overkill and really don't want to covert to -10an lol

Saifskyline

iTrader: (1)

I read somewhere that the stock fuel line from the fuel filter to rail was restrictive? The banjobolt holes are very small so replacing that with a -6AN line is better for FI setups?

EJ1_Ex

iTrader: (1)

Np bud, trying to help

Turbo-LS

iTrader: (4)

Yes the stock lines are restrictive but are still good for around 600hp. i have a banjo fitting at my tank going straight to a 8an adapter and then the rest is 8an untill the return line which is 6an. at the same boost level is richend up almost a whole point from just puttign in bigger lines.

Schister66

^^I think this is a good point that was somewhat overlooked. I agree...i dont think those 1000cc injectors are going to make much beyond 500whp, reliably. My buddy and I are building a similar setup (looking for ~500whp on e85) and are already going with either 1200cc or 1600cc and the Bosch 044 pump or a Walbro 340lph, but eventually want a twin-255 setup

LightningTeg

I just stated my setup which is the same except the injectors, and its making well over 500whp on E85...

Schister66

Whats the duty cycle at? They might be able to cut it, but I stand by my point. If this were my car, I would run something larger, but there's no point in changing now

LightningTeg

100%, injectors stuck open. I run a few lbs less on the street so really more like 530-540 in real life. But FICs are better injectors then PTEs.

Obviously if your in the planning stage theres no point in settling for something less, but that's what I had to work with last summer. I have some 1400's now, yet to be tuned.

Charlie Moua

iTrader: (3)

sorry for the confusion...
I was really only asking about the return line for 500-600whp goals.


I knew that my FIC 1000cc injectors would be fine to 500whp... and that anything beyond 500whp is all dependant on what we will encounter during the tuning session (may max out at 520whp or at 570whp) lol


I'm doubtful that I want more than 600whp, so I tend to shy away from going completely overkill on the injector size (2000cc). If there were 1400-1500cc injectors which had solid track record, I'd look into those first.

For now, I'll prepar extra fitting/relay for inline pump just incase.

Turbo-LS

iTrader: (4)

id1000's at 60 base pressure on a walbro 255 intank were maxed out at 20 pounds boost with a 58 trim garrett turbo. Yes i said 58 trim its an oddball turbo. in any event thats what was in my buddies civic si rigth before he turned the boost up and grenaded the motor. I believe it blew up at 13.7:1 a/f at 23 pounds boost. at 20 pounds it was 12.4 a/f. car trapped 128mph full weigt civic si coupe bangin off the limiter

wantboost

iTrader: (2)

For most applications the stock line is fine

The main reason I would change its age, that way you have peace of mind knowing your fuel system is in proper order. Also would be a good time upgrade to a larger line IF you for see more power in your future,

I'm doing a 10an supply (2 rails) and an 8 return, again because of the volume of fuel through 2 rails.

I'll be running hard line from the swirl pot/surge tank to the engine bay where all lines will terminate in threaded fittings to run soft braided lines to and from the motor.

Imay also have the regulator in the trunk, feeding into the surge tank... as I think my setup will run 5 bar of fuel pressure at all times (73.5psi) tthat's how one of my professional FormulaD driver friends has his setup on his S15 (Toshiki Yoshioka) and his built twin turbo vq35 makes 700+HP this way with no pressure reference to the regulator.