E38 as stand alone with manual fuel pump, ignition on, starter buttons? Wiring?

[cbr]

I need to make sure i am issue spotting before finishing wiring and going to the dyno;

I want a simple on off button for the fuel pump
simple on off for starter, as in it cranks as long and only as long as i hold the button down
I want a simple power on
I want a simple on off switch for the fan
such that the motor will fire and fun without any routines or modules

I wont have a brake switch connected, or if i absolutely have to have one it will be an aftermarket on off

this is an e38 out of an 08z, with a speartech harness, dbw, fast 102 tb,

basically just full time power button to the ecu, switched power, do i have to have a fuel pump input to ht eecm?, no speedo, no tach, (those are canbus to an aim unit)

I sure would appreciate any advice

[cbr]

Also, no neutral or clutch switch

[joecar]

Usually the ECM has a fuel pump relay output.

Also you need to disable VATS (let me locate the thread on this).

What wiring diagram are you using...?

~Moderator~

[cbr]

Thanks for answering! I really appreciate it.

Spear tech harness. Basically just power and switched power in, ground, can outs to an aim Mxg dash, and that's it through the Ecm. Planning on running the fuel pump, fan, starter, and everything else running on manual switches only, directly from battery power, not through ecm.

It appears there is no way I can get around drive by wire throttle, but hopefully having vats disabled, it will fire the injectors and coils and run fine without having any data on starter or fuel except by the crank sensor.

Will that work?

[joecar]

Yes, it will need CKP/crank and most likely also CMP/cam data.


You will have to read thru this thread, it's trial and error to see which combinations work for your ECM: E38-E67-VATS-disable-guide (https://forum.efilive.com/showthread.php?13210-E38-E67-VATS-disable-guide)

[cbr]

thx, i presume that crank and cam data will come straight from the stock sensors as hooked up and pinned in the Speedwire harness, assuming they pinned it right? I will look through that thread.

[joecar]

Yes, the harness should be pinned for CKP/CMP.

( I always like to look at the wiring diagram and verify it with a DMM )

[cbr]

i agree... but they didnt provide one, which I should not have accepted... oh well. Many thanks for your help!

[gmh308]

If its a Speartech harness it will be fine! ;)

[efiharness]

E38's do not support man throttle. Check with Speartech to see how your ignition relay is connected to run system. You don't need ecm
fuel pump control but it can become a safety issue in an accident, as soon as engine stops fuel pump will turn off from ckp signal. Steve

[cbr]

yep, pulled the cable throttle back off, there is no ignition relay with the speartech harness. It is just a fused positive into the ECM, but I do plan to give the Racepak Smartwire a try, which is a solid state programmable control board replacing fuses and relays. Is there something I need to do to make sure the ignition will fire properly whenever I have battery positive to all those 'ignition on' ECM functions?

Thanks for your help.

[efiharness]

You will need battery +, as well as ignition to the ecu. Questions? Pm me. Steve

[cbr]

ok, firing up now. or trying.... been farting with the tune for two days and would love some input.

my tune was running this motor in a 2008 z06, now its in a hot rod road race street car, no clutch switch, no neutral switch, no key, no security crap, just a stand alone fuel pump and starter button, no starter relay or anything to the ecm, ignition button turns on the 02 heaters, ecu switch + and it has stand alone + too - per the speartech harness.




It also now has a 102tb and maf, and a fast 102 intake instead of the stock LS7 ones it was first tuned on.

I took the old tune and did the vats patch, went to the vats section and set all of those,disabled the clutch switch, pwm fuel, starter stuff, etc.

I also ballparked the throttle body max area by bumping from the 4200 something to 6000

So far i cant get it to run more than a second or so and it kills itself like the vats isnt fully disabled.

I would sure appreciate some help just looking over and making sure i havent missed anything idiotic in the tune, any help would be greatly appreciated as this is the last hurdle to get it competing.

i will figure out how to post the tune real quick and edit....

[cbr]

20982

per my last post, thanks!

[cbr]

I have done everything I can think of on this update, including the VATS patch and full flash, with the proposed changes. One thing, how does the motor know that it is cranking on the starter to keep the injectors and ignition going at the startup rate? Is this coming from the crank or cam sensor? Or is this what the pin 52 grounding is supposed to trick it into? I have not thought this was the problem, as it fires up for about a second, but just making sure.

[gmh308]

Have you checked scan to see if the injectors are pulsing? The ECM knows the engine is cranking via the crank pulse. If you have added air flow via a larger TB, then likely you need to add startup/crank fuel to compensate.

[cbr]

thanks, it fires up and runs for a second, so i presume they are firing. i had some trouble getting the scan tool/v2 to work so i could not check, but I may have that figured out.

[cbr]

Also, any ideas on ballpark changes to the tune to go from the stock ls7 manifold and tb to a fast 102 and 102 nick williams tb would be most welcome.

[joecar]

Also, any ideas on ballpark changes to the tune to go from the stock ls7 manifold and tb to a fast 102 and 102 nick williams tb would be most welcome.Set it to run from MAF only (set dynamic air threshold to 100 rpm) and observe the LTFT's... you would then add this % to the MAF and VVE tables extrapolating the trend, and then tune each of MAF and VE.