Haven't been on the board in a while - car's stored for the winter.

Anyway, I've been thinking about how much that Accel in-line drives me nuts (like so many others) and I was going to try to elminate it with a Walbro 255. However, after doing some reserach in the archives, I discovered that even with a Walbro 255 you can't eliminate the in-line. It just makes the hum quieter.

So ... my question is then: what's the advantage to having the Walbro 255 over the stock if you can't elminate the in-line (other than loudness)? Does it have anything to do with boost levels? Like, if I attain higher boost, say 15lbs. with forged internals, is it better to have the higher flow rates of the Walbro, or are they negated by the in-line since the fuel travels through there last before heading to the fuel rail? I'm thinking your boost levels are more dependent on your injectors, rather than your in-tank FP.

Maybe we should all just wait and see what HRC's solution is .....

The walbro can flow well for lower fuel pressures. as the pressures rise say into the 90s or 100s then the flow drops thats what the accel helps with. With bigger injectors you dont need the high pressures, so the walbro works fine. Of course the accel and walbro would be the better choice. Get the flow rates of both pumps and look at corbin's fuel page. Dont take my info as gospel, just pointing you in the right direction. Oh and actually replying.;)

I also agree. The reason most guys still the inline, and possible an upgraded intank pump is because they're running stock or smaller injectors. Fuel volume and pressure goes hand in hand. Bigger injectors-->requires less fuel pressure; smaller injectors-->requires more fuel pressure. Of course there are other factors, such as boost level & the fuel pressure regulator that's used, that also gets figured in.

I wonder what the new fuel system is by HRC that everyone's talking about :shrug

you can also do what i did. i got 100 square feet of fatmat for christmas and that was enough to cover the interior floor and walls of my car twice!!! i did two layers on the fuel tank area, and the panels. i can hear a slight noise that reassures me that the inline is working, but i don't even hear it when the music is on and the volume is low!!!

-------jezreel
hrc stage 1, sfmu, ml, prokits, egt, boost gauge, apexi tt, costum dp, dynotune fp gauge. gst muff, turbo spoiler

nothing like driving with the windows down and the music low: i love hearing the turbo spool, swwwhhhttt!!!!
thanks for www.kaptainmyke.com for the sig hosting :thumbsup

i need to do that.. my pump is pretty loud..

Ok, that all makes perfect sense to me. So then my question is .... is anyone running just the Walbro 255 (without the in-line) at like 13lbs of boost and if so, how big are your injectors?

The point that I am driving at is that I really don't see a good valid reason for the Walbro 255 if it's just to make the in-line quieter. The noise is a nusiance, but at the same time I can live with it. I only want the Walbro if it is giong to simplify my fuel system.

I think jason esi: not really sure though. I think he has the intank hi flow pump and large injectors, no inline fuel pump. I think though, when you do run the large injectors with low pressure, then you may run into the issue of needing an safc to control idle cause the idle pressure would be soo low.

-------jezreel
hrc stage 1, sfmu, ml, prokits, egt, boost gauge, apexi tt, costum dp, dynotune fp gauge. gst muff, turbo spoiler

nothing like driving with the windows down and the music low: i love hearing the turbo spool, swwwhhhttt!!!!
thanks for www.kaptainmyke.com for the sig hosting :thumbsup

Originally posted by jsupetran
I think jason esi: not really sure though. I think he has the intank hi flow pump and large injectors, no inline fuel pump. I think though, when you do run the large injectors with low pressure, then you may run into the issue of needing an safc to control idle cause the idle pressure would be soo low.

That's right. As recent as late this summer, I removed my inline. I didn't really need to do it, as having the inline didn't hurt anything, but after implementing my 4 extra injectors,I no longer needed the inline. Additionally, I was able to get a great price from EBAY on a 8 foot -6AN SS braided fuel line and change out my fuel feed line. When I did that, I figured it was a good time to upgrade my fuel lines and at the same time, make it less complicated. 2 fuel pumps, 2 fuel fuel rails, 2 fuel computers, and 8 injectors makes for a lot of variables that can go wrong.

Currently, I have the Walbro 255lph-HP model, with that 6AN line running right off the fuel tank assembly to a 6AN Earl's inline fuel filter then to my 8 injectors. 4 are 235cc's (stock) and the other 4 are 441cc's. I then have an Aermotive 1:1 FPR. That's pretty much it. Since my fuel pressure really never exceeds 65-70psi, that's easily within the Walbro's handling ability.

all i have it a 255lph 550s and hondata
granted you guys dont have hondata..
but you would def need a afc or something better to idle them bad boys out

man i wish we had some sort of hondata

anyway...

i am not sure, but i don't think you need an safc to idle with the 8 injector set up. i have read on here that that is one of the benefits of the 8 injector set up: the fact that it sorta mimics the stock injector set up with the primaries firing at idle, then supplies extra fuel at WOT.

i am kinda thinking about the 8 injector setup for the future for my set up.

-------jezreel
hrc stage 1, sfmu, ml, prokits, egt, boost gauge, apexi tt, costum dp, dynotune fp gauge. gst muff, turbo spoiler

nothing like driving with the windows down and the music low: i love hearing the turbo spool, swwwhhhttt!!!!
thanks for www.kaptainmyke.com for the sig hosting :thumbsup

YES! It's worth it.

Especially if you're a self-concious pussy like me that gets embarrased when people come out of buildings trying to figure out what that whining noise is... ;)

I'm running the walbro at 15psi with no probs. I have 440s and use the safc for fine tuning (well, bad tuning until I can get her on a dyno hehe)

Well, personally, I am not too worried about what either people think about the sounds my car makes .... I get enough people telling me I left my car running after I turn it off right in front of them. :P

I guess I am just going to have to decide for myself whether I want a Walbro or not. After pullling my engine this winter I plan on running 30lbs 4-injector setup and hopefully 13-15 lbs of boost - if I can successfully support that. My short block has been tested at 20. We'll see .....

As always, thanks for the input guys.:thumbsup

Originally posted by jsupetran
man i wish we had some sort of hondata anyway... i am not sure, but i don't think you need an safc to idle with the 8 injector set up. i have read on here that that is one of the benefits of the 8 injector set up: the fact that it sorta mimics the stock injector set up with the primaries firing at idle, then supplies extra fuel at WOT. i am kinda thinking about the 8 injector setup for the future for my set up.

That's right you don't need any sort of SAFC for correcting idle for 8 injectors, that include the use of using close to the stock sized injectors. However, Evan was talking about the situation of ONLY using 4 550cc injectors, replacing the stock injectors, in which case you would.

i'm still trying to figure out if i really need to replace my inline or if i should get rid of it. My car is still sitting there, broken. I never really got a solid answer on whether or not the 440's and a Walbro Hi-pres would be enough to keep me around 18psi or so. Still don't want to make any fuel pump decisions without assurance.

Jon

1997 Eclipse RS

13.887@104.648 5/30/03

www.haiokuracing.com

Originally posted by HiOnPSI
i'm still trying to figure out if i really need to replace my inline or if i should get rid of it. My car is still sitting there, broken. I never really got a solid answer on whether or not the 440's and a Walbro Hi-pres would be enough to keep me around 18psi or so. Still don't want to make any fuel pump decisions without assurance.

The answer is simple. If your fuel pressure exceeds 85psi or so, I'd probably want to retain the inline. If your fuel pressures will stay below that level with your injector size and boost levels, then remove the inline (if you like), and only use the Walbro.

It's borderline. 30psi base idle on a 4:1 ratio says 92psi at 18 pounds of boost. The pump is rated to 90. God, this sucks.

Jon

1997 Eclipse RS

13.887@104.648 5/30/03

www.haiokuracing.com

with the walbro 255 and 30# injectors,and sfmu, how much boost can you run max?
doug

Originally posted by lickscissors
with the walbro 255 and 30# injectors,and sfmu, how much boost can you run max? doug

I absolutely hate these questions as well as probably most people who understand fuel/boost and so on. Anyways, it's not so much how much boost, but how much HORSEPOWER YOUR car (with its specific turbo size, compression, mods, condition,...etc.) will make at a given boost level.

Furthermore, with an adjustable fuel pressure regulator, that further puts a wrench into the matter. So what you need to do is get some baseline power numbers with your particular turbo at a low boost level, and then work from there using the appropriate fuel formulas. I don't think it's anyone else's responsibility to do that, except for you however. Moreover, it's important for you to know HOW to get there, since things will undoubtedly change for you over time with the different mods you add to your car.

Here's a great place to start in attaining those formulas: http://www.2gnt.com/www/corbin/example.html

I don't think you can run very much. I ran quite a bit more than 90psi on my 310's, you'll need at 12:1 still i believe.

Jon

1997 Eclipse RS

13.887@104.648 5/30/03

www.haiokuracing.com

I just spoke with HRC. They aren't willing to replace the pump at all. Price new is...too much. I'm gonna just go with the Walbro 255 and buy a fuel pressure gauge and see how that works out. To hell with the inline pump. It was too noisy, anyway.

Jon

1997 Eclipse RS

13.887@104.648 5/30/03

www.haiokuracing.com