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If stock fuel pump relays #1 or #2 fails, engine won't run. If either of the high voltage relays (in green) fail, the other takes over for high load. If both green relays fail, then engine runs lean under boost. I'm working on preventing this lean condition by shutting down low voltage power (through resister), which means shutting down oem Relay #2 somehow.
I can't figure out a way to shut down system when both green relays fail. Even oem system has this risk when Relay #3 fails. Only way I can think of to prevent lean condition is to use same relay for power source for resistor low voltage and full voltage. The only way I can think of to do that will need another relay to switch between the two (resistor connected to 87a while 14V connects to 87) but the problem with this setup is there is a time when there is no power to pump (when relay is switching between the two). Ugh!
Don't do this because Biggiesacks is right, resistors don't have diodes so power from green relays will go through resistor and bypass Relay #2's safety intensions.
I got it! Run 14V from left green relayto pump. If that fails, right green relay switches on and turns on a light to let driver know to replace left relay. Will this work?
Last edited by 2006EvoIXer; Feb 24, 2018 at 11:47 PM.
i think your gonna have a problem with it sticking on. If you are using the output of relay #3 to control your relays then there is a situation where they can get stuck on. The FET that drives relay #3 remains at what ever state it was in when the ecu is shut off. So if the ECU isn't sending ground to relay 3 when the engine shuts off your circuit will get stock on. This can happen if you had say a crank to no start, or a stall (the ecu will go full voltage on the pump as some function of low idle). In that situation you would be unable to shut off the pump. So what im saying is if your relays are active when the car shuts off, power will back feed through the fuel pump resistor through the normally closed relay 3 and then back into your relay coils basically keeping them stuck in a loop. The only way to get them out of this is to send ground to the coil on relay 3 and opening it, which you would need either the ecu to do or you could install like a switch or something to pull it to ground.
Thanks Biggiesacks! Took a while, but I see it now!! Hmmm......
And now I don't see it.
When ECM turns on Relay #3, it breaks connection from resistors to green relays and forces power to go through resistors. But you brought up something big. It can povide power through resistors when Relay #2 turns off (when CAS is no longer detected) thereby, bypassing Relay #2's safety cutoff. This only happens when engine is under boost when CAS dies and when engine isn't running (uh-oh). So my fuel pump will keep pumping until I shut off engine with key (Relay #1). Does this sound right?
Last edited by 2006EvoIXer; Feb 23, 2018 at 07:53 PM.
Do you have the wiring schematics of the fuse box? I'm thinking about putting a relay in series from Relay #2.
Originally Posted by Biggiesacks
i think your gonna have a problem with it sticking on. If you are using the output of relay #3 to control your relays then there is a situation where they can get stuck on. The FET that drives relay #3 remains at what ever state it was in when the ecu is shut off. So if the ECU isn't sending ground to relay 3 when the engine shuts off your circuit will get stock on. This can happen if you had say a crank to no start, or a stall (the ecu will go full voltage on the pump as some function of low idle). In that situation you would be unable to shut off the pump. So what im saying is if your relays are active when the car shuts off, power will back feed through the fuel pump resistor through the normally closed relay 3 and then back into your relay coils basically keeping them stuck in a loop. The only way to get them out of this is to send ground to the coil on relay 3 and opening it, which you would need either the ecu to do or you could install like a switch or something to pull it to ground.
Working with (and stealing from ) Biggiesacks, I think this is best because there is redundancy if Relay #3 fails. No need for redundancy since relay failure will result in full power to pump and bypassing resister. I will just add a volt meter for pump to see if it ever stays at 14V permanently.
Last edited by 2006EvoIXer; Feb 24, 2018 at 11:32 PM.
Yes. I have AEM 320 lph pump with RC1200 (which is really 1090cc). Hitting 104% IDC. Max power out of stock wiring is about 460 hp on E85. Getting larger injectors can increase power but injectors get super expensive over 1100cc ($900ish vs $500). Stock wiring doesn't support larger than stock pump very well. Stock wiring isn't designed for 15A draw, so this is more of a necessary upgrade with aftermarket pumps.
If you are planning fir 550whp or more, you'll need a double pumper. Under 550whp, I'd stick with single pump for simplicity (dual voltage setup and small 1/4" return line).
Originally Posted by dookgvr4
why the pump rewire? are you running out of pump?
I am trying to decide whether to upgrade to this pump from my 255, or if i should get a double pumper for my fp red e85 setup
If you're constantly pushing 35+ psi boost, double pumper is probably the better choice. Maybe you can get by with single Wally 450 pump rewired, but eventually, you'll want more boost and you don't want to upgrade twice.
Originally Posted by dookgvr4
why the pump rewire? are you running out of pump?
I am trying to decide whether to upgrade to this pump from my 255, or if i should get a double pumper for my fp red e85 setup
Here is the left relay pins 86 and 87 connections (in series with factory power source output from Fuel Relay #2 that goes to Relay #3.
I ran out of regular solder wire, so I bought lead free solder wire...big mistake! I can't get it to completely melt on wires. I have leaded solder wire now and redid this relay.
Last edited by 2006EvoIXer; Mar 6, 2018 at 08:40 PM.
Looking for advice on how to port intake manifold. I'm thinking to match port the throttle body part to the gasket diameter and same with the gasket to head. How do I port deeper i to the runners?
Looking at these pictures, my guess is the bowl provides some sort of antisurge from the valves opening and closing (like protection from water hammers for you plumbers). The narrowing of the passage increases the speed to air going right at valves. This is great for midrange power. I'm so tempted to smooth this whole area out! I have the HTA71, so I won't mind a tiny bit more lag. Since there's no way to polish my head without removing it, I'll have to wait until that time comes around. Maybe I'll start looking to build an evo starting with a shell and only restore the bare essentials for a street car.
Originally Posted by TrendSetter
Pretty much any time i have the head off one of my cars I throw a little bit of portwork at it. I used to do this stuff for work so its pretty easy to do some basics now and then when the opportunity arises.
I have done a few 1g and 2g dsms back in the day so i had a pretty good game plan for this one to begin with.
the die grinder i use and my favorite burr for this stuff.
this is a before, i ran the bit real quick on the surfaces just to get some light in there
right side on this one you can see i am moving the wall out. These ports are pretty big at the gasket surface then get pretty narrow right before widening back up at the bowl. I like to try to open up the sides a lot(the amount depends on how extensive i want to port, this is a 'medium-ish' kind of job since i daily drive my evo). on a head like this i usually wont open up the port at the gasket surface at all, its already the largest part of the runner.
this is a neat trick to gauge how straight the wall is and how your curve looks. it is very hard to tell by just looking but you can feel it by running your finger through the port. my old 1g head i made the walls all straight but this head im leaving some venturi in it. a little bit for flow but mostly because i dont feel like spending that much time on it and dont want to risk breaking through the port wall.
this is a good tool for making all your ports the same. its called a divider. when you start moving a lot of material deep in the port you lose most any kind of reference geometry so tools like this help a lot. you want all ports to be as close to the same as possible.
here is the start of working on the divider wall. i tend to make them straight and fairly sharp. left side is done, right side is stock
here is the center divider with both sides done
i usually dont move much material from port floors because of how important the short side is, but i do like to raise the port roof as much as i feel is safe. in the old 1g stuff i would cut the entire valve guide out and make the roof completely smooth but i didnt really want to push those boundaries with this head so i just cleaned them up some and raised the roof everywhere i could.
the short side is critical. very easy to cut too much material out.
The bowls can be tuned for certain RPM pulse where the necking down continues to pressurize bowl for next valve opening. So when valve opens, there is already pressure to start filling the cylinder. I would barely clean up the end of the port into the bowls and really clean up the bowls for perfectly smooth mirror finish and maybe remove a slightly bit more. I'd probably smooth the neck to perfect smooth finish at gasket and less towards end in bowl to keep velocities up. Very interesting...
Feb 22, 2018, 09:07 AM
