I was recommended the AEM-1200's by trbo vnm. Using some of the online calculators they should get me over 800rwhp on e85 before I have an issue.
700-750 with a twinscrew likely. Mine were at 100% DC with a 12:1 AFR at 705rwhp with no bap on 100 octane. I'm figuring a BAP would be good for another 30-40%
GT's + bap with pump gas are barely good for 600 man.. been there done that
GT's + bap with pump gas are barely good for 600 man.. been there done that
Many have done it plus some..... not sure where your getting that from. With that said you need a modified fpdm or a dual setup.
GT's + bap with pump gas are barely good for 600 man.. been there done that
I prefer in tank pumps as I can turn them on and off when needed. Which you cant do with in line external pumps.
I was return with them and they still weren't enough. It's documented out there that it works for some and not for others
First off there are better/cheaper return pumps than the ford gt pump. Ford gt is phenomenal for a returnless system. But a cheap standard walbro gss gerotor 255lph pump actually flows better than a ford gt pump in a return configuration. The gerotor pump in return puts out less heat and will flow more like 260-265lph from the get go. And can be had for $70 a pump. Cheap and reliable, great for your always on idle/cruise pump.
This is not aimed directly at you, I have seen this many times. It wasn't a pump issue specificy, flow wise they are more than capable of making 600rwhp+. When systems don't make what they are supposed to guys often throw bigger pumps or baps at it rather than diagnose and correct the initial problem. Don't blame guys either, its often easier, but I have seen many times it be something as simple as dirty fuel filter, loose wiring or inadequate base pressure or poorly setup return system, it will put a lot of heat in the fuel and flow starts dropping a lot as heat goes up. Especialy in a return system.
Most pump flow ratings are established at 125 degrees Fahrenheit, a 75-100 degree increase in fuel temps will results in a 25-30% drop in flow for your average 39mm armature pump, that's substantial. (The dual channel single stage 39mm/50mm armature pump only see a 5-10% drop in flow when hot so they are a better performing "street" pump as they will handle the heat better) I've seen poorly setup return systems with fuel temps in the 180+ degree range on the return. The problem is your standard return system completely bypasses all the oem safeguards to keep heat out of the fuel system. To compensate we just throw bigger lines or pumps at it instead of optimizing your system and setup for your needs which will get you to the power you want safely while prolonging reliability and pump life. As heat goes up flow and pump life go down.
Some tips to prevent this.
-Run adequate wiring to the pump(s) 10-12 gauge minimum from a dedicated power source with a reliable relay trigger. This is step one to healthy system. If the wiring is not adequate the pumps are going to draw more current and not flow at the advertised rating from the get go, and it will only get worse from there as the pumps run longer and the fuel gets warm outside temps etc.
-Minimize the pump amount and size to safely make your max power goal, anymore and your just adding heat. Make sure you give your self some head room. I like to do 10-20% more fuel than you max power goal.
-Deactivate pump(s) you don't need when just idling cruising, hobbs switches are your friends.
-Factory systems use rail pressure and temperature sensors to maintain pressure and prevent fuel vaporization in the lines and rails. A return system does not have this. On a hot day when the engine bay is heat soaked the pcm will raise delta pressure to keep the fuel from boiling. So for a return system you need to set your base pressure high enough to prevent this. I will tell you on a 100 degree day a 39-40psi base pressure is inadequate to do this. This is a double edge sword though remember as you raise base pressure max pump flow will go down so plan accordingly and you don't want pressure too high. For most a 43-50psi base pressure is adequate depending on climate and use of the car.
Sounds like a lot of pump for 1000rwhp+ setup, two on the hobbs switch would be the way to do it though for a street car.
What kind of Hobbs switch do you use, Ive seen different styles. I'm wanting to do this to turn off 2 of the 3 walbro 255 pumps I'm running in the fore tripple hat.