S54 Swap Question

[Wanganstyle]

quite interested in knowing how the S54 added weight + lee's booster will work out.

My e36M+s54 had a decrease in braking feel with the original e36m booster items all retained, possibly due to lack of vacuum from mini accumulator rail in comparison to the single throttle s52

[rThor432]

quite interested in knowing how the S54 added weight + lee's booster will work out.

Me too. I've got Lee's booster-delete setup and a modified plenum, so I'm not sure which route I'll take yet.

[FredK]

I dont know why you'd want to delete the relay? It should extend the life of the pump, keep the fuel cooler, not to mention being quieter. Is there some electrical complication preventing it's use in an e30?

I wouldn't want to drive 24\7 at 5 bar pressure. I wonder if they retuned the fuel for that? Maybe its an on/off multiplier variable?

I think it's been deleted. I don't think it's hard to use, but I'm not sure of what technical challenges it might present. I sourced a PWM relay "just-in-case".

Well, I have the fuel pump ON signal hooked up at X60002 pin 11. It is definitely a PWM output. I hooked up a standard Bosch relay and it buzzed like crazy, so I replaced it with a PWM relay I harvested from an E46 M3.

[nando]

that's good!

I've been trying to find that relay for bench testing, BMW parts lookup for relays sucks.

[E30Strube]

Is PWM the brand or type? What does that designate? I'm just using a standard relay right now.

[nando]

pulse width modulation

the M3 fuel pump runs at a variable speed, it only runs full speed under full load/WOT.

[e30shmobberr]

this could be a wiring issue, no? at least for the s50/52 it sounds similar to the c101/x20 wiring issues that people have.

[E30Strube]

As a follow up to this, I picked up a MZ3 harness to replace the E46 M3 harness that I spliced (needed to make it longer). I've just been too lazy to actually put it in. I will probably get it done this weekend.

[Fernflex]

As a follow up to this, I picked up a MZ3 harness to replace the E46 M3 harness that I spliced (needed to make it longer). I've just been too lazy to actually put it in. I will probably get it done this weekend.

Where did you got the harness or do you have the part number? I need one for my swap.

[SpeedRacer85]

Yo this is cray, could I come see this in person I stay in kemah I would like to test the waters with the s54 in my e30 great job bro.

[anaphe]

Yikes, you're right. X60004 pin 1 is the battery charge indicator.

The DME is powered at pin 7 and 8 on X60001. It should be an "always hot" at X60001 pin 7, as it's Terminal 30 and should be continuous with the battery positive (B+).

X60004 pin 26 and X60001 pin 1 are "power with key on". X60004 pin 6 is the start signal and needs to be hot only while starting.

Where does Pin 8 of X60001 get is + from ? Is it switched? I have power at 7 but not 8. 8 is a red wire candy striped yellow with a white trace on it. it goes to the engine block wiring cover and is pigtailed to some smaller ones.

Thanks

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