924Board.org

[CorsePerVita]

So I'm having a hard time deciding how I want to do this. I saw stefan's idea with the trigger wheel. But what about pertronix? They do make it for our cars, could pertronix essentially be used with the stock distributor to provide a trigger point for the input on the MS? Seems rather than having to close that off and go through a bunch of hassle of locking that up since it's being removed you could use the original distributor, hook up pertronix and use it as a trigger point.

Am I incorrect?

I was thinking if you locked down the distributor and disconnected it's ability to vacuum advance, creating a static trigger point, it could be used to the input for the ignition for the megasquirt, which could be used for the map and therefore the output on the megasquirt with an electronic ignition system.

Anyone? Bueler? Bueler?

I can go the trigger wheel route, but figured I'd throw this out there as a possible alternative and grab some feedback.
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- 1977 Porsche 924 2.0 N/A (Trackday Project)
- 1979 Porsche 924 2.0 N/A (The other daily)
- 1980 Porsche 931 (Daily)
- 1987 Lamborghini Jalpa
- 1999 Ducati 900SS

[CorsePerVita]

Alright nevermind, the triggerwheel idea seems more efficient.
_________________
- 1977 Porsche 924 2.0 N/A (Trackday Project)
- 1979 Porsche 924 2.0 N/A (The other daily)
- 1980 Porsche 931 (Daily)
- 1987 Lamborghini Jalpa
- 1999 Ducati 900SS

[Scorpio]

Blocking off the distributor hole is quite simple.. I think I have a write up somewhere about my trigger wheel solution, not sure if it works yet but should do
_________________
1979 NA
MS1..EFI..
GARRETT T25 TURBO
BILSTEIN SHOCKS
GT BASED CUSTOM BODYKIT

Brisbane , Australia
Think mean think fast
all youll see is
my Porsches Arse!!!

[fiat22turbo]

You could also mount a smaller trigger wheel in the distributor to run the EDIS with the appropriate mount for the sensor.

Just leave the cap and rotor off and use the coil pack to drive the plugs.

Someone even got coil-on-plug to work on these cars.
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Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[RC]

You`re right on with your OP there CorsePerVita. You don`t even need anything but the stock VR coil pickup signal if using the MS VR input or similar add-on circuit. The Pertronix unit will give a squarewave output signal but is really unnecessary.

I was quite successfully running with a mechanically locked dizzy on NA and for a while boosted. No issues. Subsequently up graded to sequential CNP using 4 x LS2 coils. TBH, although it is technically superior, and I can measure the difference, it was not felt on the butt dyno at the time. Running @ 14 PSI boost now, it does provide more than ample spark and confidence in the system. Not necessary IMO for a NA however.

BTW, personally would not suggest a COP on the NA head, due to the close proximity to the exhaust and thermal rise in the coils, also the limited space constraints. Spent much time researching the issue and all the available COP units. Am now confident the LS2 coils was the right decision and most probably the top of the shelf as far as ignition goes on these cars.

Have a good read of the appropriate sections of the Megamanual. The Extra site & manual has good basic info on the various ignition set ups: Yes, I know it is overwhelming with all the info and difficult to absorb in a short time. Anyone such as yourself, that can resurrect the most rusted 924 ever, will have the patience and determination to cope though.

Welcome to the lower rungs of a very steep learning curve indeed.

http://www.megamanual.com/mtabcon.htm

http://www.msextra.com/doc/index.html
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World`s quickest 924 2L slushbox

[CorsePerVita]

Thanks guys, trying to take it all in. I'm as excited as all get go to get this car finished. Megasquirt is fun, I'm so glad I veered from CIS because this is quite an adventure.
_________________
- 1977 Porsche 924 2.0 N/A (Trackday Project)
- 1979 Porsche 924 2.0 N/A (The other daily)
- 1980 Porsche 931 (Daily)
- 1987 Lamborghini Jalpa
- 1999 Ducati 900SS

[RC]

[Lizard]

You can also cut the end off the camshaft and then just put a plate over the hole at the back of the head. I would use Hondabond, or Yamabond to seal it.
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3 928s,

[Mike9311]

RC, what alternator (generator) are you using and how much does it weigh?

Nice meticulous detailed work BTW on that ignition setup.

Mike
_________________
1980 931 since 1989
1981 Ideola 931 Club Sport
1982 931 Entwicklungsfahrzeug
1979 924 NA ohne 650 mit 471
1982 931 Red Resurrection - 951 IC
1982 931 parts car / resurrection?
1980 924 NA (R&D lightweight)
1982 931 wana-be GTR race car

[Joes924Racer]

[Joes924Racer]

Speechless .. nice pics.

[fiat22turbo]

[flosho]

RC, want to wire me up some fuel injector pigtails like you have there.. Those look nice. I'm jealous.
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[This Space For Rent]

[morghen]