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View Full Version : Pulleys for distributor-less crank fired ignition



cygnus x-1
10-19-2007, 09:55 PM
Recently there has been some interest in converting to crank fired distributor-less ignition, here and over at PreludePower. The advantage of
this over a mechanical distributor is that you have exact control of the spark timing for all RPM and engine load conditions; which is really nice if you have any significant engine mods. And since it's totally electronic there are no more distributor parts to wear out.

The interesting thing about this conversion is that most of the parts can be scavenged from mid-90s Fords. Depending on your level of DIY skill you can do this mod for as little as about $200 in parts. The major hurdle for most people though is getting a trigger wheel mounted to the crank pulley.

So I'm considering modifying a few stock pulleys to mount trigger wheels on to be compatible with Ford's EDIS ignition system. They would look similar to the one I made for myself, except that I would probably leave the power steering groove on instead of cutting it off but either way is possible. I ripped out my PS so don't need the extra pulley groove.

At this point I'm just trying to gauge how many people might be interested in something like this. All I would be doing is converting stock pulleys by cutting off the AC groove (and maybe PS if desired) and mounting up a 36-1 toothed trigger wheel. The rest of the conversion is up to you. I have no idea on the cost but I'll guarantee that it will be between $20 and $100. The parts will cost $20 at a minimum and if it's more than $100 it's probably not worth it. Unless people REALLY want these.

So... Comments? Questions? Flames?

C|


Oh, here is the one I made for myself:

http://bluegreenlabs.com/Prelude/Mods/FIConversion/CrankPulley-TriggerWheel2.jpg

coope
10-19-2007, 10:07 PM
great mod but i don't wont nothing off a ford lol

labeledsk8r
10-19-2007, 10:15 PM
i have seen atleast one person looking for crank trigers that i can think of, its not gona be a real big market though, was that done to a B20a5 for a lude? i dunno how good there pullys are but i know the A20 pully is very um well its crap, they chip and are week, might wana see about doing this mod to custom crank pully

2ndGenGuy
10-19-2007, 11:46 PM
How did you make sure it's balanced?

2oodoor
10-20-2007, 02:32 AM
looks good cygnus and YES I am one of those interested in converting to crank fired ign.
I am concerned about balance and shaddering though. Your prototype looks like it could use some sleeves or a machined spacer, I am a little wary of the exposed threads. I am sure you were carefull about snugging that thing down without distorting the ring.

For my own car, I know it is just a matter of time before I have distributor problems, so with that expense in mind I would just assume convert to something like electromotive or home made edis frankenstien. That would put me in line with any future mod of forced induction or multilple carb setup, and nitrous










ed

bobafett
10-20-2007, 07:50 AM
I don't need one built, but I think this is a pretty sweet idea, and if you can get them balanced perfectly, I think its a GREAT idea.

Also you might consider using a 60-2 wheel as well, which is compatible with some of the other EMS systems (not sure if it will work with a EDIS/MS2 type setup though).

Roodoo2, it looks like he does have spacers on there, and not exposed threads, at least to my eyes thats what it looks like. The ring also looks thick enough that it wouldn't be distorted much as long as it was torqued on there with all of the spacers in place (which I'm sure it would be).

For reference the electromotive kit uses trigger wheels that are 1/8" thick, so his trigger wheel is going to be WAY stronger than mine!

Anyway I think this is great because hopefully it will help to pave the way for more member using alternative engine management systems like the EDIS/MS2 or any of the several other that get rid of the dizzy (yay!).

PS if you are shaving the pulley, attaching the trigger wheel, and balancing the unit, I would not expect this to cost less than $100 even if the person supplied their own crank pulley (and you supplied hardware and trigger wheel/ring).

2oodoor
10-20-2007, 08:00 AM
I think I see them now,, it was early..lol

Zufer
10-20-2007, 09:31 AM
why is everyone so worried about the balancing, as long as the crank trigger is mounted centered the whole piece could then be blanced just as a flywheel or crank pully normally would be.

BTW this is awesome, i think that tuning is often overlooked and stand alone is definitely the way to go to get a really good tune

bobafett
10-20-2007, 09:33 AM
yes it should be balanced just like a flywheel.... i would just stress that it gets balanced at some point before you start the engine with it.

cygnus x-1
10-20-2007, 10:02 AM
Ford parts on a Honda:
I know. It's so wrong! But they actually did something right with the EDIS ignition. It's really simple and works great.

B20A5:
No. Those were in 3g Preludes and are totally different animals from "A" engines.

A20 crank pulleys are weak:
Eh? Really? I've never heard that before. And given how heavy and thick they are I have a hard time believing it. A custom pulley would be far more expensive.

Balance:
I didn't balance mine but I was very careful to get the bolts spaced evenly and align the trigger ring with no run out. Because the pulley has a fairly small diameter the balance is not as critical as say a flywheel or tire. But I would like to find a way to balance pulleys that doesn't involve taking them to a shop and paying $50 each. I have an idea though for a way to balance these, so if I end up making them I'll try out my balancing idea. And no, I couldn't possibly do this for under $100 if I had to have them balanced at a shop.

Trigger wheel mounting:
The trigger wheel is ~1/4" thick steel. There is no way it will break. It's spaced off the pulley with aluminum spacers that I checked to make sure they were the same thickness. The pulley surface was machined flat and square relative to the crank mounting surface to eliminate distortion and lateral run out. The radial run out was also checked after the wheel was bolted on to make sure that the trigger signal is consistent. The mounting bolts are 5mm with nuts on the backside. I was thinking about tapping the holes in the pulley but there isn't a lot of thickness there and I was concerned about them stripping out. Probably I would use nylock nuts for any more that I build for vibration resistance.

Non EDIS:
EDIS will only work with a 36-1 wheel so no go on the 60-2. MS2 is configurable though and should work with a 60-2. But in that case you would still need a distributor to route the spark signal to the correct plug. So not much advantage there.

C|

bobafett
10-20-2007, 10:07 AM
I 'think' (but not positive) that some other standalone systems can use a 60-2 wheel with distributorless ignition. I know for a fact that the Electromotive stuff can, and probably several others... You would just need an EMS that is capable of handling spark. Granted the EDIS/MS is the most common for DIY EMS so it is probably the most practical to build them this way. :)

Anyway, carry on...

2oodoor
10-20-2007, 03:02 PM
No, hyundai parts on a Honda would be just so wrong,

Balance issues= these pulleys are not harmonic balancers, there are no insulators pressed in them. I think they are factory balanced at part of mfg. process.
I do think that when you start adding hardware it could start some radial vibrations that could affect crank end thrust, and end bearing cap wear eventually. I think if the ring is well balanced, and they should be as part of the desgn of being a rotating signal counter (one would hope) , if the attaching hardware process was carefully done, these should be ok. Not like they are going to be spinning 12,000 rpm (again, one would hope)
Great job cygnus, your explanation eased my mind a little ....and yes definately look at nylocks or maybe some fine thread bolts, maybe some type of graded alloy hardware, and tap some threads, thread locker...count me in.

MessyHonda
10-20-2007, 04:58 PM
some cranks are weak...on my dx my uncle was taping it out when the lip part of it chiped off.. it sucked cuz we had to go to the junkyard and get another one for like 12 bucks.

labeledsk8r
10-20-2007, 05:58 PM
Ford parts on a Honda:
I know. It's so wrong! But they actually did something right with the EDIS ignition. It's really simple and works great.

B20A5:
No. Those were in 3g Preludes and are totally different animals from "A" engines.

A20 crank pulleys are weak:
Eh? Really? I've never heard that before. And given how heavy and thick they are I have a hard time believing it. A custom pulley would be far more expensive.


C|


my bad lol i just saw prelude lol i for some reason thought that your year was a 3rd gen lude so my fault

and yeah some of the cranks i have workd with are weak as hell, i have chiped one very badly once just doing i normal removal and re-install, i have been doing research for aluminum crank pullys and i think if you had money to convert to stand alone an extra 50-100 on a new crank wouldnt be to bad. i really like this idea as there arnt very many options out there for tuneing wich makes hitting higher numbers much harder, good to see someone opening options up

cygnus x-1
10-21-2007, 08:53 PM
There is NO WAY we will ever get aluminum pulleys for the A20AX for less than $100. Not even remotely. It would just be too expensive unless you could have a large number of them made.

Anyway, went to the junkyard today to see what I could find. I discovered that the pulleys from mid '90s Escorts were really easy to remove so I picked up 3 of them. I also grabbed 3 trigger sensors, 3 ignition modules, and 3 coil packs. So I can save a couple people the effort of having to go scrounge parts.

I checked out several Accords and a Prelude DX for pulleys. Unfortunately I couldn't get any of them off (need an impact wrench) so I can't confirm that they're all the same. The Accords all appear to use the same pulleys but I remember something about some of them having different crank nose diameters. The Prelude DX is an all V belt pulley so it's different.

I won't be able to get back out to the junkyard until next weekend at the earliest. It would save me some time if someone could sell me an extra pulley they have around. Even better would be if I had one of each with the 2 different nose diameters. So if you have an extra one let me know. I already have a Prelude DX pulley so don't need any more at the moment.


Roodoo2, what kind of pulley do you need? And will you have power steering or no?

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Demon1024
10-21-2007, 10:33 PM
A20 crank pulleys are weak:
Eh? Really? I've never heard that before. And given how heavy and thick they are I have a hard time believing it. A custom pulley would be far more expensive.


C|

http://a305.ac-images.myspacecdn.com/images01/89/l_0fd158d4e6907adbfe9aae5aabf14d28.jpg

x2 weak

AccordB20A
10-22-2007, 01:35 AM
every crank pulley will do that if you lever on it/bash it. the car i sold had one that had bits missing but it still operated :)

2oodoor
10-22-2007, 11:07 AM
Yes to power steering, I like having it
let me look at mine this week, I was going to be taking off the crank pulley to do some work anyway. I think I am more inclined to go with the EDIS escort type, parts would be easier to get when replacements are needed.

sb_hbackDX
10-24-2007, 06:32 PM
Cygnus x-1 I have been working on home-made prototypes for distributor-less ignition for awhile actually on other cars without EFI. After the hurricane I lost all my tools/car parts and accessibility to machine shops/junkyards in New Orleans and in Lafayette, LA ,where i live now, they're both quite sparse. Plus I'm slowly rebuilding and going to school .When I discovered your developments for the EDIS man I had a gigantic smile across my face! Thats exactly what I was trying to do, good job btw! Of course its EFI but I'm beginning to venture from the carby world too. It seems no one wanted to go distributor-less...Its tons easier. I really didn't want to go OBD-1 but I was gathering parts for it until now. I'm planning on turbo charging the ole fella and I am rebuilding a block as of now so I was looking for tuning options without going OBD-1. Anyways enough of my blabbering I would like to say I'm VERY interesting in getting a hold of your custom cranks w/ PS and if possible the control module and coil packs that come along with it. Pricing from $50-$100 correct per crank? How about the rest of the EDIS stuff? How much would that be? Also I wouldn't mind paying $50 extra to get that thing balanced...I mean if its really necessary. Thanks a bunch man! O how is MegaSquirt treating you? Never used it before but have seen it in use...pretty user friendly?

sb_hbackDX
10-24-2007, 06:40 PM
O yea in PP you said you were having a problem getting the tachometer to trigger with EDIS and MS right? Well try this...

"If your tachometer was previously driven by a single coil, and the IDM signal doesn't work, your tachometer will need input from two coils to indicate properly. The trick is that you need to tie all the coils together, without allowing them to ground each other. Below is a simple circuit (with Digi-Key part numbers) showing how to interface the EDIS system with your tach"


http://img145.imageshack.us/my.php?image=edistachfe6.gif


Hopefully that should do the trick!

cygnus x-1
10-24-2007, 09:43 PM
Hey SB,
I'll put your name on a set of the EDIS parts. And a pulley too. The EDIS parts would be $75. I don't have a price on the pulleys yet. Still working on that. I'll let you know when I get it worked out.

With the tach thing, you definitely need to tap into both coils. I did the diode trick and it works great. Which reminds me, I should get some diodes too to send with the rest of the parts since they're so cheap and I can get them locally.

The Megasquirt is working out great. I don't know if I would exactly call it user friendly but it's amazingly flexible. I've never used any other EMS so I can't compare it to anything else. For the cost though I doubt you can beat it.

C|

Hauntd ca3
10-28-2007, 12:04 AM
why mount the gear on the crank pulley
has anyone thought of using the flywheel
alot of them have timing marks on the flywheel for a start
and since the weight of the flywheel is so much, it would be
easier to balance the thing if at all needed
and since its of a far larger diameter, you can make more acurate timing marks to work from being further from the crank center

2oodoor
10-28-2007, 03:18 AM
I plan on using this with a carbed car. Are we locked into one timing curve? how do we interface to chnage that?

Using the flywheel is not a bad idea, but there is already hardware to do it on the crank. If you were to start back to square one I am sure a flywheel signal and reader could be done, go for it!

cygnus x-1
10-28-2007, 08:40 AM
Ford's EDIS ignition is designed to work with a 36-1 toothed wheel and won't function with anything else. The flywheel has way more than 36 teeth on it so you can't trigger from that. It's also much harder to get to since it's inside the bell housing. There also needs to be a tooth missing so that the controller knows where TDC is.


:ugh: It appears I forgot to mention the most important part here, which is the controller.

http://www.autosportlabs.com/megajolt-lite-complete-sensor-option-p-30.html

With this controller the timing is completely adjustable for load and RPM. Load is based on engine MAP and is monitored with a built in sensor. Here are some pictures of the configuration software. You can also download the configuration program and mess with it, even if you don't have a controller yet.

http://www.autosportlabs.net/index.php?title=MJLJ_Configuration_Software

This is where the DIY part comes in. If you can solder you can save some money and build the kit yourself. There is also a pre-assembled kit if you can't solder or just want to save some time.

C|

2oodoor
10-28-2007, 08:55 AM
thanks again cygnus, wheww... Im on board but be pateint with me:)

building the circuits is not a problem at all for me,, Im glad you are filling in the blanks :cheers:

2oodoor
10-31-2007, 03:22 PM
excellant link, I was looking at one similar a few months ago but it was hard to get it all, that one was straight forward.

I need to buy the mJ lite controller and then get the rest from you or the pulley and the edis parts from a 4 cyl fomoco, correct. I dont really think it needs to be balanced. I will wait and see how much you develop the prototype:)

cygnus x-1
10-31-2007, 04:07 PM
Right. I should probably put together a complete parts list with sources and stuff. I'm starting to think now that I'll have to try using the larger type trigger wheel instead of the smaller one like I used. Because of how wide the sensors are the wheel has to be spaced off the surface of the pulley a little bit, but if it's out too far it will interfere with the PS belt. With the larger diameter wheel the teeth will be out (radially) just past the alt. belt groove, so the wheel can be mounted flush instead of spaced out.
The bad part is that the larger rings are more work to get off the car to begin with. The good part is that they are bolted to their native pulleys instead of press fit, so they won't have to be cut off the Ford pulley like the smaller ones. Another trip to the JY. Yay!

I talked to my machinist buddy yesterday; and as it turns out the machine he normally uses to do this kind of stuff (modifications on existing parts) has a problem with the X axis (meaning it's basically a manual machine at the moment). So I need to see if I can fix it before we do the pulley stuff on it (see * below). Otherwise we have to work out a way to do it on his machining center. He normally only uses that for more complex or multi-part jobs; the stuff that keeps him in business. So he doesn't like to do easier one off kinda stuff on it.
The other issue is that he's moving to another location in roughly 2 weeks. So there will be a short transition time where he won't be able to do any work. It don't think it will be a problem but just something to work around.

Anyway, we'll figure it out.

C|


* Once in the past this machine had a computer problem (it's PC controlled) that I was able to fix, saving him a call to Bridgeport tech support and the cost of a tech coming out to look at it (big $$). So now he always calls me when it has a problem. It's kinda like those people that find out you know something about computers and always want you to fix theirs when they do something stupid like install one of those "Internet Speed Booster" programs that really just hoses their system with spy ware. I swear I need to get one of those shirts that says "No. I will not fix your computer." I guess he's really not that bad though, and he does help me with machine work. So in the end it's cool.

2oodoor
10-31-2007, 04:30 PM
sounds good
I havent been to a JY in months, I need to go see what is up there.. Honda wise... and
Ranger trucks? tempo, escort, any mazdas? I know some of those are inside the timing cover, some on the outside.

Hauntd ca3
11-02-2007, 03:27 PM
I plan on using this with a carbed car. Are we locked into one timing curve? how do we interface to chnage that?

Using the flywheel is not a bad idea, but there is already hardware to do it on the crank. If you were to start back to square one I am sure a flywheel signal and reader could be done, go for it!

i know of some after market ecu's that can run two differant fuel and ignition
maps, just so the mechanics cant thrash it when its in for a service

With the flywheel trigger , i'd imagine that if you could tell the ecu or what ever controller you were using how many teeth there were between tdc for each cylinder it should be able to do it.
I mean if you need to mark each cylinders tdc, there would be away of doing it
sink a magnetic plug into the fly wheel at those points or something along those lines.
would be a challenge, but a worthwhile one i'm sure

cygnus x-1
11-02-2007, 06:44 PM
I don't see any advantage to triggering from the flywheel. Especially since the EDIS system works so well and is so simple.

As for EDIS parts; they're found in lots of models. Once you know what the parts look like you can just rummage around until you find something. Escorts and Tracers are probably the easiest to find since they sold millions of them. Like Civic's.

C|

2oodoor
11-07-2007, 06:33 AM
I don't see any advantage to triggering from the flywheel. Especially since the EDIS system works so well and is so simple.

As for EDIS parts; they're found in lots of models. Once you know what the parts look like you can just rummage around until you find something. Escorts and Tracers are probably the easiest to find since they sold millions of them. Like Civic's.

C|

Im getting mine from you since you volunteered to assemble some.. but I was at the JY yesterday and hell I didnt realize there were so many different engines in the escorts.. I never did see a gear, some were DIS but no gear unless it was inside the cover. I was on my luch break so I didnt have a lot of time to explorer I got distracted by the antique car lines.

2oodoor
11-10-2007, 02:16 PM
I was reading up on EDIS, there are a lot of car collectors going to this. I see where it is easier to get the trigger wheel from taurus and mustang V6 engines, same teeth and not pressed on.
I ran across an IMP forum, wow.. My dad had a Simca back around 1966, I have never seen another one other than the pictures of his...until today. Interesting stuff, that company was bought by Chrysler and that is where the bodys for Cricket and Omni came from. Yes even IMP fans are going EDIS. Now to write Santa for MJ lite jr...

cygnus x-1
11-16-2007, 03:08 PM
Just a quick update:

The machine shop is about to move to another building (tomorrow!) so will be down for a few days. The Bridgeport is fixed though so it should be ready to go after the move.

I did start on the prototype using my little lathe though. Have a pulley now with the AC groove cut off and a trigger ring ready for mounting. Now just need to get the holes drilled in the right places and bolt together. Then can try test fitting on the car.

C|

2oodoor
11-16-2007, 03:42 PM
what are some well tried methods of mapping the T curve. I am reading various ideas, some using pdr and some other devices that write to the MJLJ?
carbed carbed carbed

cygnus x-1
11-17-2007, 09:16 AM
what are some well tried methods of mapping the T curve. I am reading various ideas, some using pdr and some other devices that write to the MJLJ?
carbed carbed carbed

For setting the timing map in the MJL you can use any PC with a serial port. If you don't have a serial port you can use a USB to serial adapter. For actually mapping the curve with a stock distributor, that's something I haven't tried yet. I have a map for my Megasquirt that should be pretty close for most A20s. One of these days I am going to try and reverse engineer the curve from a stock distributor though.

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sb_hbackDX
12-24-2007, 11:45 PM
How are things going with those pulleys buddy? I have since gathered all the other components for the EDIS system(some brand new and others jk special)...just waiting on those results for the pulleys.







Happy Holidays btw :cheers: and that goes for all my 3geez buddies !

newaccorddriver
12-26-2007, 03:52 PM
do you have a picture of the finished product? i just want to compare it to what i did to my pulley during spring

bobafett
12-26-2007, 04:18 PM
Not 100% relevant, but my modified trigger wheel from electromotive came a while ago. I need to take the trigger wheel off and hit the pulley with a light coat of paint to keep it from rusting, but then I will take some pictures of it. Looks pretty excellent.

My wheel uses a 60-2 wheel for use in the Electromotive TEC-GT system, but you get the idea...

newaccorddriver
12-26-2007, 07:27 PM
heres my motor with the trigger wheel welded onto the crank pulley itself. i just wanted to see someone elses for comparison and to see if it can be improved in the event i decide to build another motor up

http://i59.photobucket.com/albums/g303/newaccorddriver/IM000733.jpg

2oodoor
12-27-2007, 11:33 AM
http://www.3geez.com/forum/showthread.php?t=63342
cygnus I am posting the link from the other thread here, it pertains exactley ^^^^


bobafett Re: Pulleys for distributor-less crank fired ignition

--------------------------------------------------------------------------------
Not 100% relevant, but my modified trigger wheel from electromotive came a while ago. I need to take the trigger wheel off and hit the pulley with a light coat of paint to keep it from rusting, but then I will take some pictures of it. Looks pretty excellent.


the cliche comes to mind "a rolling stone gathers no moss" :)
Clarification :you mean paint the pulley and not the trigger wheel ? , Im not sure even that is a great idea, do not want paint inside the pulley or paint making the surface uneven so the wheel wobbles a bit.

bobafett
12-27-2007, 12:16 PM
yep painting the pulley. the trigger wheel is zinc coated and will not need paint to stay rust free.

light coat of paint. :)

the stock coating is all gone from when the machine shop balanced and acid dipped it. it will rust badly (already started to rust) if i don't hit it up with some flat black rustoleum. I agree that lots of paint could affect it adversely, but I will be careful not to go overboard. but yeah the mating surface will probably be masked off. it shouldn't rust too bad if i put some oil or something behind it to keep it from oxidizing etc...

cygnus x-1
12-30-2007, 09:42 AM
How are things going with those pulleys buddy? I have since gathered all the other components for the EDIS system(some brand new and others jk special)...just waiting on those results for the pulleys.

Happy Holidays btw :cheers: and that goes for all my 3geez buddies !

Unfortunately progress has pretty much stalled in the last month. Just too much going on during the holidays.

Anyway, I just sent my machinist friend a 3D file of a mounting jig for the pulley and trigger wheel. The jig will make it much easier to run multiple parts with repeatable results. I can do everything with manual machines, but it's slow and each one would be different.
So hang in there guys, we'll get it going.

C|

2oodoor
01-10-2008, 12:17 PM
Hrmm, I am wondering if there is a MSD product that is equal to the MJ jr, that would work for this EDIS set up.. I was looking through the Summit catalog and there must be a couple dozen controllers. I have not researched the specs on them yet. It seems like the rest of the world is using the MJ jr with borrowed EDIS parts though. MSD looks to be more expensive I see.
(have summit gift card, and they have no MJ products listed, errrgh)

2oodoor
01-15-2008, 02:30 PM
^^incoherent babbling I guess

There are several brands in Summit that have simiilar capability as MJ jr, but I guess a proven avenue is the way to go without buying stuff that isn't going to work as well.
I can use the gift card on A/F meter or something.

cygnus x-1
01-16-2008, 05:45 PM
I looked at MSDs web page and I didn't see anything in their ignition products that would help here. And they are quite expensive. I think the MJ + EDIS combo will be hard to beat price wise.

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Hauntd ca3
01-23-2008, 11:48 PM
I've been lookin into this type of dizzyless ign as wel and think have a post in this thread.
after some digging thru the old text books etc have found a way i think will work
i plan on using subie inductive pick ups and using the flywheel ring gear as the trigger
all i need to do is fig a way of taking a tooth of the ring gear as a tdc reference or add an extra tooth butted up against one,as to make a tooth twice as long to give same tdc ref point.
also investigating usin subie coils
as in one per cylinder mounted on the plug itself
all this will need an aftermarket ecu to run it but i think will work and be well worth it.
am "borrowing" pickup and coil from a dead subie motor at work
will try and get some pics as i go so to show you'se all my idea

cygnus x-1
03-23-2008, 01:30 PM
Just a note, I haven't forgotten about this project. In fact I should have a few pulleys done in the next couple weeks. I've been putting up with a lot of crap from my job and haven't had much free time. But I've finally had it with those bozos, so I gave them my 2 week notice. As of April 1st I will be unemployed and will have plenty of free time for fun projects :D. At least until I find another job.

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2oodoor
03-23-2008, 02:55 PM
I wish you well, and thanks for chiming in.. I have taken on a few other projects on the Accords to keep me occupied meanwhile..:wave:

Oldblueaccord
11-20-2014, 01:03 AM
Bttt.

cygnus x-1
11-20-2014, 09:53 AM
Oh wow, this is old! LOL!

I have made a few of these since then, although it's more difficult now since my source for cheap toothed rings (pick n pull) is gone. Need to find another source.

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JSmythe
11-20-2014, 07:55 PM
Use the dizzy gear or Cam to run a 72-2 trigger wheel. Some of those pictured are from an RX-7. You can get them at McMaster Car for $40

http://i.imgur.com/qPn6UZy.jpg
http://i.imgur.com/LajGYQL.jpg
http://i.imgur.com/JixTwuF.jpg
http://i.imgur.com/X8Whp2E.jpg
http://i.imgur.com/Oo7PDgy.jpg
http://i.imgur.com/baFieby.jpg
http://i.imgur.com/rxjmHcD.jpg
http://i.imgur.com/pKjkLTA.jpg
http://i.imgur.com/XE2VdYi.jpg

cygnus x-1
11-21-2014, 09:54 AM
I've wondered about whether a 72-2 wheel would work when run off the cam. For something like that though I might be inclined to go with an optical encoder (with index pulse) instead of a VR trigger. Optical encoders are fairly cheap now and can be more compact.

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