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So I've been trying to get this 13b carb conversion with electronic dizzy timed, and I'm not sure what I'm doing wrong and any help would be appreciated.
It has a 13b, electronic dizzy with an MSD-6A wired to two blaster type coils, stock ignition wires, stock plugs, and the trailing is using a gm igniter routed through the dizzy. The inside of the motor has been modestly ported, but running on stock carb jets.
When it's in time (yellow mark lines up with little pin on the front with timing light), it runs horrible, sounds like a v6 with lopey cams, has terrible response and backfires. Yet when it's completely retarded, like can't even see the red or yellow dot anymore, it runs a lot better, shakes less and has more response.... So....anyone...What the ****?
Hey, Ralph is trying his best...
Sorry, but I had to do that...
Anyway, it sounds like the Dizzy wasn't installed correctly. Search for "stabbing the CAS" in the 2nd Gen Section for more info on it. In the Eunos Cosmo Workshop Manual (shameless self-plug...lol), getting it off by one tooth will throw off timing by about 30 degrees.
Thanks I'll look it up, sorry I'm a bit new to this. I know engines but me and my dad swapped this thing into a Datsun 620 a few years before he passed away and he was kind of in the middle of changing some things around. He was a master technician and used to work for Mazda as well so he knew what he was doing but I sure as hell am having a hard time learning this engine haha. It sat for a long time so I've had to do a lot of rewiring, tried my best to get it timed and whatnot but just haven't learned enough I think. I'll have a look at what you suggested and see if that helps, thanks!
[QUOTE=Akagis_white_comet;12519298]
Anyway, it sounds like the Dizzy wasn't installed correctly. Search for "stabbing the CAS" in the 2nd Gen Section for more info on it.
So I just checked and I have a 12A distributor, should I get something different or is that normal?
I'm sorry, but Distributors and Carbs are outside of my expertise. It appears that yours has a Vacuum advance mechanism on it, although I am not sure how it would affect things in this scenario. The GSL-SE has a distributor too, but I'm currently cut off from my catalogs and other resources. To make a long story short, I was trying to clone a drive this morning but the source (WD drive) and destination (Toshiba drive) drives got mixed up somehow between selecting them and clicking "begin" in DDRescue-GUI (Linux). I aborted the procedure after 2.5 hours and 29gb written (~1%), but the damage was done. The WD drive's File system messed up, drive won't mount in Ubuntu and so on.
Thankfully, a good friend of mine is experienced in Data Recovery and the drive that was inadvertantly cloned was blank and brand new, except for a single URL shortcut file in a folder so only 4.1kb of actual files were written, the rest was formatting information. And thanks to due diligence, I isolated both drives promptly before things got messier. He thinks that since it was caught so soon, relatively speaking, that he can recover the majority of what was on the WD drive without too much drama and put them on the Toshiba drive.
Again, my apologies as I'm unable to help you on this matter.
So anyway, it sounds like your distributor was installed with the gear teeth misalligned by one or two teeth. This might not be the problem, but it's fairly easy to remove and reinstall the dizzy, and it does sound like your issue.
First put the car in Neutral. Then take a 19mm or 3/4 deep socket ant turn the main pully (the big, lower pulley) clockwise until the first mark lines up with the pointer needle.
Now undo the distributor cap clips and move the cap and wires out of the way. Is the dist. rotor pointing to the L1 wire position? It should be. If not we need to remove the dizzy and re-install it correctly.
To remove the dizzy unhook all wiring going to it - wires/plugs to both ignitors and a small wire between the vac. advance pots. Remove the "timing adjust" screw that holds the dizzy in, and pull it straight up and out. There is a bump on the dizzy body that needs to be aligned with the dimple on the black gear...
When that is lined up, the rotor arrow will point to the L1 spark plug wire. This is right in the middle of the vac advance pots...
Now you can re-install it. Slowly slide the dizzy back in with the "timing screw" hole slighty to the left...
As the teeth engage, because they are on an angle, the dizzy will spin slightly clockwise as it seats. If all goes well this will result in the dizzy being centered on that screw, and the rotor arrow still pointing at the L1 plug wire. If not, try again.
That's the basic "how to set timing on a 12A" guide. If the motor was ported or turboed or something, it would get more involved. But for a basic carbed motor that's it.
Old-timers... If I messed anything up, please correct me.
05-22-22, 12:18 PM
