Still on track for a kit from SpoolinUp. We are looking at electromechanical relay options.

 

Great news MrFred, i for see this being one of the most popular upgraded parts for 2012. continue to make the community bigger n better sir

 

That piece is RATED at 23A continuous current when heatsinked.
There is also the AUIR3330 that is rated for 45A continuous that uses the same leads. There is plenty of capacity in there and that 7mOhm rating actually includes the leads.

FWIW, 18AWG TEFZEL wire is rated for 24A, to put size requirements in perspective.

I have to assume that since the circuit isn't really opening up and stopping current flow when this circuit switches that arcing really should not be a problem. Any automotive grade relay should hold up just fine despite the high number of cycles it will see.

Now if it was actually breaking the circuit all together and you had the inductance of the pump trying to force a back voltage on the switch, the quality of relay would matter more.

 

Yeah, I called IR tech support last week and found out about the 23A continuous rating. Its an interesting option, but I think we're going to stick with EM relays.

I generally agree with you on the lack of driving force for an arc with the high/low relays, but if you ever followed the Evo 10 relay issue that was causing Evo 10's to run lean, it was the high/low voltage relay that was getting trashed by arcing. I popped open the high/low EM relay I had been using for no more than 500 miles, and the contacts looked nearly perfect (as it should for such low miles). There was just a thin black ring around the contact area.

 

well i was really looking forward ssr option for this.

 

sry for bumping the thread and a couple of stupid questions, but perhaps someone looked into that already.

can we use green/blue fuel relay from evo x (the one they're replacing oem black relay with) for doing that rewire?
from what i've read it's spec'd for 35 amps and normally opened. also, widely available.
do we need a diode with that?

 

Yes, it can be used, but I don't think it has the standard 5-prong plug configuration, so it woudl be necessary to attach each wire to it one-by-one rather than using a standard automotive relay receptacle.

 

it is standard, but seems to be of micro iso standard.
can be hooked up with these parts.

socket: bosch 3 334 485 046
connectors (2x): tyco(amp) 42238-2 / bosch 1 901 355 975 4.8 x 0.8 mm
connectors (2x): tyco(amp) 42282-2 / bosch 1 904 492 016 6.3 x 0.8 mm

i still don't know if a diode is needed.

perhaps spoolinup will do the right kit?

 

I found one company that makes the standard size receptable with the diode attached to it rather than built into the relay. Would be pretty easy to build the diode jumper into the receptable if you want.

 

that is a really good idea, particularly now that the walbro 416 is available it needs all the power it can get in an E85 application

 

i just realized that with only a bit more additional wiring, i can do a three step voltage setup. this would give 100% control over fuel pressure with the factory fpr and fuel return system. guess i'll have to get working on this...

 

what would the purpose be having three different voltage levels? are you referring to basically just having a high/low factory setup then a "boost a pump" sort of situation on the third voltage? plus any luck on your idea, would love to hear how this is going

 

there is no way to avoid some overrun when using the walbro 400/465 pumps with the stock return system and the factory dual voltage setup. i can get pretty close to perfect but not quite. drilling out the siphon hole can potentially fix the issue, but i haven't verified it yet. a three-step voltage would fix it for sure.

 

Just curious, is the control pin 55 (or 21) from the ECU just a discrete on/off or can you control the voltage to the pin?

 

on/off.