[Paul Westcott]

Originally Posted by speedshopmike

anyone running a distributor with a pickup only, no module, and letting the ecm fire the ignition box at the right time (ie, letting the ecm control, directly, igntition timing)
like to hear from street users of any decent efi system that has self-tuning and wideband capability, please.

I run all fuel and ignition via Megasquirt II. HEI reluctor triggers the ECU and MS does the rest -no module needed (see attached pic). I tried using the HEI module and it never did run right, so I got rid of it and went direct. Works perfectly! I agree with krisr; quality wiring is essential and I did have to hang capacitors in a few places to suppress RF noise.

[speedshopmike]

thanks, paul.
what are you triggering the MS to? - msd style box, or just a coil?

[TheMonkey]

Originally Posted by Paul Westcott

....I did have to hang capacitors in a few places to suppress RF noise.

what were symptoms of the problem?

[krisr]

Stumbles & hesitations I bet.

[Paul Westcott]

Originally Posted by speedshopmike

thanks, paul.
what are you triggering the MS to? - msd style box, or just a coil?

I use a MSD6AL box and MSD coil.

FYI - My brother uses Megasquirt to run his cross rammed EFI 426 Hemi in his '68 Dodge Superbee. He has 2 - 670 cfm TBs and triggers MS with a Ford EDIS 36-1 timing wheel and mag pickup. It has twin 4 cyl. coil packs and uses no distributor at all. He did the Power Tour with it (Long Hauler, no less) and put 6K highway miles on it last year!

Originally Posted by TheMonkey

what were symptoms of the problem?

krisr knows....! Stumbles and hesitation, but only at ~1000 RPM. Caps helped quiet things down and made a big improvement.

[speedshopmike]

paul, did you need the caps in the MS's wiring or in the car's oem wiring?
thank you
mike
ps - i see you're running a holley 900 TB; is it the old analog version?
until the crossram came along, i was going to convert my analog TB to MS...

[Paul Westcott]

Mike- I put the caps across non-oem stuff like the input to the MS relay board, MSD trigger wiring, electric fuel pump, cooling fan relay, etc. ...Anything that might put out RF noise. It was trial and error without a scope but each step lessened the problem until its no longer an issue.

I'm using an older Holley 900 CFM TBI with 4 x 85lb/hr. injectors ...is there a newer version?

[speedshopmike]

oh, fun...is your battery in the back or oem location?
holley TB's - the newer version uses an IAC vs a solenoid, otherwise identical as far as i'm aware.
oh, untrue - i believe the newer one has progressive linkage vs simultaneous butterflies.
mine's the older one, which used an analog control box vs digital.
thank you for the info; do you mind if PM you at some point and bother you with questions?

[speedshopmike]

it seems MS is rather vulnerable to RF or EMI or AC ripple?
comments?

[Paul Westcott]

Originally Posted by speedshopmike

oh, fun...is your battery in the back or oem location?
holley TB's - the newer version uses an IAC vs a solenoid, otherwise identical as far as i'm aware.
oh, untrue - i believe the newer one has progressive linkage vs simultaneous butterflies.
mine's the older one, which used an analog control box vs digital.
thank you for the info; do you mind if PM you at some point and bother you with questions?

Battery is up front at this point. Analog or digital, none of the Holley control boxes are needed with Megasquirt as it computes everything on the fly. My TBI has fully functional IAC and came with the simultaneous butterflies, but I cut a slot in the linkage to make it progressive. Unfortunately, I had to go back to the simultaneous mode until MS is reprogrammed to stage the front and back injectors. That will make throttle tip-in and driveability much smoother. It's way too easy to send the rear tires up in a cloud of smoke when all 4 barrels open up at once!

You're more than welcome to PM me, although I'm primarily the 'wrench turner' while my brother Tom is the EFI electronic wizard!

Originally Posted by speedshopmike

it seems MS is rather vulnerable to RF or EMI or AC ripple?
comments?

No. -No more than the off the shelf types we've messed around with. My MSD box is the main culprit. The RFI, EMI, and just plain electrical noise from the MSD is really intense and oddly enough, seems to make the system more vulnerable to other sources. Long battery cables from trunk mount locations also require added suppression. Our EFI Hemi project only required noise suppression for the trunk mount battery, as it has no MSD. Each vehicle is different.

[speedshopmike]

with you on no need for the holley boxes; was just providing info relative to the TB.
i'm running a crane hi6 box, which is usually quieter then an msd...we'll see.
also with you on the non-progressive holley linkage; i couldn't keep the tires from smoking every time i tried to gently get moving.
the TB's i'm using on the crossram are progressive, so i'm hoping for nice off-idle driveability.
if not easy-going enough, i'll restrict the primary bores to gentle them out.
this'll net me at 600cfm per TB, times two, which is very more then adequate airflow for my combo.
i really appreciate the info.
as arnold said, "i'll be back" (with more questions)

[speedshopmike]

how do you think MS is going to like a progressive butterfly TB setup, and the primaries will be smaller then the secondaries?
will auto-tune deal with it in closed loop do you think, or willit need a "step" programmed in manually to account for the non linear airflow?
thanks
mike

[Paul Westcott]

SSMike:

Check your PM re: your last post.
Thanks.
Paul

[speedshopmike]

paul,
thanks a bunch.
-mike