Here goes :confused:

I reciently made a distributor for my charade. The standard setup is contact points. I designed and made a electronic distributor from a handful of parts i had lying around. I retrofitted a toyota crown 6cylinder reluctor to my dissy shaft, a suzuki swift pickup and ignitor unit to the distributor baseplate/housing and went about installing.

Now the spark is great, the car has oodles more torque and when the missfire is gone, it pulls right to 8500 like it never has before.

The missfire is at half to full throttle and only in a select rpm range, from 3000 to 6000 rpm. It drives through the missfire reluctantly spluttering but still climbs rpm but past 6000rpm it carries on doing what its built to do, rev hard. I can use less than half throttle and easily climb the revs with no sign of missfires until redline, but it doesn't build boost and gets their slowly.

If anyone has ANY ideas, be them obvious or technical I need to hear them! This problem is giving me grief and i can imagine it will be something pretty simple to fix, like i forgot something stupid in the design phase or machining/building phase :doubt:

http://turbocharade.kicks-ass.org/files/temp-images/dissy/IMG_0080.jpg
http://turbocharade.kicks-ass.org/files/temp-images/dissy/IMG_0081.jpg

Pics show how i have modified the reluctor for 3 cylinder applications :bowrofl:

Out of my ball park sorry.. :confused:

IF the vehicle is an EFI vehicle then the problem is more than likely "Noise" from the magnetic reluctor setup which tend to be veyr noisy. This "Noise" is picked up as usually a RPM spike and is a very commen problem with magnetic triggers.

This is one of hte main reasons why EFI vehicles tend to run a hall effect sensor which is a square wave signal and is pure digital. No noise issues and tends to be a stronger signal.

I would suggest getting an oscilliscope onto the signal wire which woudl of course feed back to the factory ecu via the tacho signal, and see if it is pulsing or having fluctuations.

Thats one idea anyway.

mitsiman: Unfortunatly i dont have an osiliscope lying around, and now im finnished uni i dont have access to that sort of gear, plus i only did that stuff for 6 months back in 1st year mech engineering. the noise your talking about is normaly caused by HT leads running very close to the ignitor wires (correct me if im wrong) so when i installed it i made sure i was well clear.

Did you see my reluctor, do you think i should chew a bit more of the redundant teeth?

what do you think.

Actualy one thing i didn't check was the gap between the reluctor and the pickup pole once installed. I will check that tomorrow.

ego: thanks ill try that :P

8500 daaaam TC. :shock:

Could be noise interference, could be a simple advance problem.

I like the work though, good lateral thinking. :thumbsup:

I would probably grind back the other 3 lobes (just for looks) but if they were causing the trouble you would have thought they would do it across the revs not at one point. Same for the noise interference.

Try getting the advance curve mapped to see if anything odd is occuring, most mech's should have the gear 2 do it. :D

I know the timing curve theoreticaly.

Mechanical/centrifugal advance is 20 crank degrees, so 10 cam degrees
vacuum advance is 26 crank so 13 cam degrees
boost retard is 17 crank and 8.5 cam degrees

centrifugal advance kicks in at 1800rpm and is in full effect by 3000 rpm. throttle is half depressed so there is probably 7 or 8 degrees vacuum advance applied making it 18 degrees advance plus static which makes 28deg. if i keep revving out the motor at half throttle then the timing pretty much stays around that mark, maybe loses a bit more timing because of less vacuum.

when at 3000-6000 rpm and wot (when the missfire is occuring) the timing should be 10 static, 10 centrifugal and between 0-8.5 degrees lost by boost retard. so between 12-20 degrees.

past 6000 once it clears up timing would be spot on 11.5deg (10 static + 10 centrifugal - 8.5 boost retard)

ive been looking over timing for ages and actualy custom made weight and springs for the desired centrifugal advance and onset rpm.
is their a problem with any of that brian or mitsiman?

edit: thanks for the compliments brian, but its not 100% yet lol

The theory is sound but it may not actually be doing that. If you get it mapped you'll know for sure.

Be a real piss off if it was just some wierd ass resonant detonation caused by carbon build up wouldnt it. :badgrin:

just to add something. 1st gear doesn't do it. wound it up to 17psi today but could only grace the odd falcodore with a 1st gear squirt :badgrin:

Anyone have any simple ideas? ANY at all im very very desperate.

????????????????????????????????????WTF

Errrrrrrrr.....pixies maybe lol

checked for pixies, couldnt see anything pixie related.. still have no idea. it doesnt bother much much, the car still drives and has enough power without boost to do all i need to do.


I documented the build and research, all pretty standard boring stuff :bowrofl:

bit more information
http://www.dairally.net/daihard/chas/ElectronicDizzy/ElectronicDizzy.htm

build process
http://www.dairally.net/daihard/chas/ElectronicDizzy/ElectronicDizzy2.htm

advance curve, mine is a little different due to mild modifications
http://www.dairally.net/daihard/chas/Dizzy/CB60Dizzy.jpg

check for a crack in the distributer or trails from where a spark could be misled.

sheriff

dissy cap cracks? i will recheck tonight, thanks.

checked for pixies, couldnt see anything pixie related.. still have no idea. it doesnt bother much much, the car still drives and has enough power without boost to do all i need to do.


I documented the build and research, all pretty standard boring stuff :bowrofl:

bit more information
http://www.dairally.net/daihard/chas/ElectronicDizzy/ElectronicDizzy.htm

build process
http://www.dairally.net/daihard/chas/ElectronicDizzy/ElectronicDizzy2.htm

advance curve, mine is a little different due to mild modifications
http://www.dairally.net/daihard/chas/Dizzy/CB60Dizzy.jpg


Just put a new coil in, High Energy Coil 716, bosch unit. Did help torque a little down low, but didn't cure the main problem.

I have a new dissy cap on its way from japan, might as well replace it. Plugs are getting a little fouled up because of the constant missing, but its not making the problem any worse.

I have tripple checked the design and it should all be schmicko, its giving me the ****s!

I have a new rotor button..

Maybe i should just cut my losses and call my home made custom distributor a failure and put back in the contact points unit.

Patience grasshopper.

At least wait till you try the new cap. :D

i looked at the rotor button today while i was bored at work, and there are 3 burn marks 2mm from the centre contact mark, exactly 120 degrees away

seems as if its arcing instead of going through the sprung contact on the inside of the dissy cap its arcing around it :confused:

so new cap and magnacore leads later, still has the miss.

it MUST be a faulty pickup or ignitor unit. i had more than one dissy housing machined out for possible resale, im going to have to use it and make a second one up with new components not from wreckers :rant:

Doh :rant: :rant: :rant: :rant: :rant:

im at work now just throwing it together making sure its all lined up properly. i got second hand ignitor and pickup unit again, but i tested them both out before installing this time :doubt:

im at work now just throwing it together making sure its all lined up properly. i got second hand ignitor and pickup unit again, but i tested them both out before installing this time :doubt:

Ya eva considered working at work, just a thought. :cool:

http://turbocharade.kicks-ass.org/files/temp-images/rotor.jpg

I made another distributor up, replaced the cap and rotor and its still doing it. Im going to see a auto lecky about it this week unless I find the problem today.

Ya eva considered working at work, just a thought. :cool:
dont be stupid :P