E85 on single fuel pump???
actually, razorlab found that switching from the stock rail to an aftermarket rail on a 460 whp (GST's MD) evo allowed him to make another 20+ whp. for anyone making 500+ whp (DJ) on e85, a big rail is cheap insurance against uneven fuel/afrs across the cylinders.
At 500 whp, the stock fuel supply line causes 16-18 psi pressure increase at the pump. add 43 psi base pressure and say 27 psi boost pressure, and total pressure at the pump is 86-88 psi at the pump. there isn't much flow from a walbro 255 at that kind of pressure. when flow rate drops off, pressure at the rail starts dropping. most people don't realize how badly fuel rail pressure is falling off because up to a point, its possible to tune around it. another interesting tidbit is that pressure increase due to the fuel line goes as the square of the flow rate, so for instance at 550 whp, the pressure increase at the pump due to the supply line is 20-22 psi, and at 600 whp, its 23-26 psi. 90 psi is when the flow of most fuel pumps starts dropping like a rock. a significant fuel system upgrade is a good idea for anyone planning to make 550+ whp on e85. a single pump setup like a walbro 400/460 needs either an upgraded fuel supply line or a kenne bell boost-a-pump. a double pumper can work well up to 600 whp because the custom fuel hose that comes with it replaces the most restictive part of the factory supply line (three very restrictive sharp 90 degree connectors).
At 500 whp, the stock fuel supply line causes 16-18 psi pressure increase at the pump. add 43 psi base pressure and say 27 psi boost pressure, and total pressure at the pump is 86-88 psi at the pump. there isn't much flow from a walbro 255 at that kind of pressure. when flow rate drops off, pressure at the rail starts dropping. most people don't realize how badly fuel rail pressure is falling off because up to a point, its possible to tune around it. another interesting tidbit is that pressure increase due to the fuel line goes as the square of the flow rate, so for instance at 550 whp, the pressure increase at the pump due to the supply line is 20-22 psi, and at 600 whp, its 23-26 psi. 90 psi is when the flow of most fuel pumps starts dropping like a rock. a significant fuel system upgrade is a good idea for anyone planning to make 550+ whp on e85. a single pump setup like a walbro 400/460 needs either an upgraded fuel supply line or a kenne bell boost-a-pump. a double pumper can work well up to 600 whp because the custom fuel hose that comes with it replaces the most restictive part of the factory supply line (three very restrictive sharp 90 degree connectors).
actually, razorlab found that switching from the stock rail to an aftermarket rail on a 460 whp (GST's MD) evo allowed him to make another 20+ whp. for anyone making 500+ whp (DJ) on e85, a big rail is cheap insurance against uneven fuel/afrs across the cylinders.
At 500 whp, the stock fuel supply line causes 16-18 psi pressure increase at the pump. add 43 psi base pressure and say 27 psi boost pressure, and total pressure at the pump is 86-88 psi. there isn't much flow from a walbro 255 at that kind of pressure. when flow rate drops off, pressure at the rail starts dropping. most people don't realize how badly fuel rail pressure is falling off because up to a point, its possible to tune around it. another interesting tidbit is that pressure increase due to the fuel line goes as the square of the flow rate, so for instance at 550 whp, the pressure increase at the pump due to the supply line is 20-22 psi, and at 600 whp, its 23-26 psi. Again, add boost pressure and base fuel rail pressure to get total pressure at the pump. 90 psi is when the flow of most fuel pumps starts dropping like a rock. a significant fuel system upgrade is a good idea for anyone planning to make 550+ whp on e85. a single pump setup like a walbro 400/460 needs either an upgraded fuel supply line or a kenne bell boost-a-pump. a double pumper can work well up to 600 whp because the custom fuel hose that comes with it replaces the most restrictive part of the factory supply line (three very restrictive sharp 90 degree connectors).
At 500 whp, the stock fuel supply line causes 16-18 psi pressure increase at the pump. add 43 psi base pressure and say 27 psi boost pressure, and total pressure at the pump is 86-88 psi. there isn't much flow from a walbro 255 at that kind of pressure. when flow rate drops off, pressure at the rail starts dropping. most people don't realize how badly fuel rail pressure is falling off because up to a point, its possible to tune around it. another interesting tidbit is that pressure increase due to the fuel line goes as the square of the flow rate, so for instance at 550 whp, the pressure increase at the pump due to the supply line is 20-22 psi, and at 600 whp, its 23-26 psi. Again, add boost pressure and base fuel rail pressure to get total pressure at the pump. 90 psi is when the flow of most fuel pumps starts dropping like a rock. a significant fuel system upgrade is a good idea for anyone planning to make 550+ whp on e85. a single pump setup like a walbro 400/460 needs either an upgraded fuel supply line or a kenne bell boost-a-pump. a double pumper can work well up to 600 whp because the custom fuel hose that comes with it replaces the most restrictive part of the factory supply line (three very restrictive sharp 90 degree connectors).
I presently have the Magnus 100cfm fuel rail sitting uninstalled in my garage alone with the necessary fuel lines. I was told that it would not be necessary by the shop that did all of my installation work. Reading this post, I see that even from a peace of mind perspective, that I should have it installed considering that I will most certainly be in the 525whp range on E85 with my EF4 turbo. I will take +20whp as cheap insurance any day of the week. I presently have a single Walbro 255lph and I know that it can in no way whatsoever pump enough for what my goals are. I like the thought of how the double pumper "de-restricts" things and along with the upgraded fuel rail, looks to be a safe and worthwhile path to pursue.
i love the "cheap route" aspect of thinking on this forum. i'm not one to just throw out misinformed suggestions, i should have elaborated, but MrFred did it better than I could have.
yes very good info. Mychailo so there is more power to be had due to the cylinders all running a closer AFR vs prior with the stock rail its all over the place? it sounds kind of dangerous when you think about it like that.. im glad i have the AMS rail going on soon.
Last edited by tscompusa; May 22, 2012 at 06:51 PM. Reason: reworded myself
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That's the takeway from Bryan's tuning info he's posted over the years. If you're on the stock rail now, I'll be very interested to see what your AFRs do after putting in an aftermarket rail. At your power levels on E85, you might want to consider something larger in diameter than the AMS rail. I think its only 9/16" ID whereas there are several 11/16" ID rails out there now.
actually, razorlab found that switching from the stock rail to an aftermarket rail on a 460 whp (GST's MD) evo allowed him to make another 20+ whp. for anyone making 500+ whp (DJ) on e85, a big rail is cheap insurance against uneven fuel/afrs across the cylinders.
At 500 whp, the stock fuel supply line causes 16-18 psi pressure increase at the pump. add 43 psi base pressure and say 27 psi boost pressure, and total pressure at the pump is 86-88 psi. there isn't much flow from a walbro 255 at that kind of pressure. when flow rate drops off, pressure at the rail starts dropping. most people don't realize how badly fuel rail pressure is falling off because up to a point, its possible to tune around it. another interesting tidbit is that pressure increase due to the fuel line goes as the square of the flow rate, so for instance at 550 whp, the pressure increase at the pump due to the supply line is 20-22 psi, and at 600 whp, its 23-26 psi. Again, add boost pressure and base fuel rail pressure to get total pressure at the pump. 90 psi is when the flow of most fuel pumps starts dropping like a rock. a significant fuel system upgrade is a good idea for anyone planning to make 550+ whp on e85. a single pump setup like a walbro 400/460 needs either an upgraded fuel supply line or a kenne bell boost-a-pump. a double pumper can work well up to 600 whp because the custom fuel hose that comes with it replaces the most restrictive part of the factory supply line (three very restrictive sharp 90 degree connectors).
At 500 whp, the stock fuel supply line causes 16-18 psi pressure increase at the pump. add 43 psi base pressure and say 27 psi boost pressure, and total pressure at the pump is 86-88 psi. there isn't much flow from a walbro 255 at that kind of pressure. when flow rate drops off, pressure at the rail starts dropping. most people don't realize how badly fuel rail pressure is falling off because up to a point, its possible to tune around it. another interesting tidbit is that pressure increase due to the fuel line goes as the square of the flow rate, so for instance at 550 whp, the pressure increase at the pump due to the supply line is 20-22 psi, and at 600 whp, its 23-26 psi. Again, add boost pressure and base fuel rail pressure to get total pressure at the pump. 90 psi is when the flow of most fuel pumps starts dropping like a rock. a significant fuel system upgrade is a good idea for anyone planning to make 550+ whp on e85. a single pump setup like a walbro 400/460 needs either an upgraded fuel supply line or a kenne bell boost-a-pump. a double pumper can work well up to 600 whp because the custom fuel hose that comes with it replaces the most restrictive part of the factory supply line (three very restrictive sharp 90 degree connectors).
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Unless you plan on a rewire, I doubt the combo will support the power properly, i.e., fuel pressure will likely be falling off on stock pump wiring, especially if running high boost up top. If I could do it all over again, I'd do a Buschur double pumper or build my own.
Unless your running a Hobbs switch your just gonna melt one of or both of them if they run at the same time.
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On the supras, we run two and three Walbros at a time in the tank with no switch. That is what the fuel pressure regulator is for.
Last edited by supercompact; Jun 7, 2012 at 07:32 AM.
Correct me if I am wrong but wouldn't this setup need a FPR as well?
Definitely a lot of useful information in here! Do you guys think a set of fic 1050s would be capable of supporting roughly 480 whp on e85? I decided to go with a ported ef2 and even with all the supporting mods I doubt ill break 500 horses and as such idk if ill need to go up to 1250s
Definitely a lot of useful information in here! Do you guys think a set of fic 1050s would be capable of supporting roughly 480 whp on e85? I decided to go with a ported ef2 and even with all the supporting mods I doubt ill break 500 horses and as such idk if ill need to go up to 1250s
https://www.evolutionm.net/forums/ev...l#post10223253