12A BP static timing
#1
12A BP static timing
hello,
Can anyone give me a write up on how to set the static timing?
I am going based of the racing beat timing for bp which says Leading 24 BTDC and 5 BTDC at 6k so i assumed around 16 BTDC for leading.
I have those marks on the pulley so i set front cover marker to those marks on the pulley, pulled the dizzy and lined up the dimple with the notch and put the dizzy back in the front cover. Is this the correct process?
How do i set the static trailing?
Can anyone give me a write up on how to set the static timing?
I am going based of the racing beat timing for bp which says Leading 24 BTDC and 5 BTDC at 6k so i assumed around 16 BTDC for leading.
I have those marks on the pulley so i set front cover marker to those marks on the pulley, pulled the dizzy and lined up the dimple with the notch and put the dizzy back in the front cover. Is this the correct process?
How do i set the static trailing?
#3
The trailing is just gonna follow what the leading is doing. So if you moved your distributer X degrees both the trailing and the leading changed.
By static you mean locking the distributor? If you just want to limit the amount of advance you can dick with the advancer spring in the distributer, and the slots the advancer moves in. It will limit the amount of advance when the engine hits higher RPMs.
To put the distributor in the front cover...
take the cap off of the distributer.
line up the marks on the shaft
rotate the engine to TDC
shove the cap less distributer into the front cover
then twist the distributer until the pickup coil for the leading ignition moves over the sending unit for the leading ignition.
EDIT: this will set the distributer up to fire as the factory suggests. If you want more or less advance instead of putting the engine on TDC move it to wherever and it will fire at that point in rotation.
By static you mean locking the distributor? If you just want to limit the amount of advance you can dick with the advancer spring in the distributer, and the slots the advancer moves in. It will limit the amount of advance when the engine hits higher RPMs.
To put the distributor in the front cover...
take the cap off of the distributer.
line up the marks on the shaft
rotate the engine to TDC
shove the cap less distributer into the front cover
then twist the distributer until the pickup coil for the leading ignition moves over the sending unit for the leading ignition.
EDIT: this will set the distributer up to fire as the factory suggests. If you want more or less advance instead of putting the engine on TDC move it to wherever and it will fire at that point in rotation.
Last edited by Qingdao; 05-07-16 at 07:50 PM.
#5
The trailing is just gonna follow what the leading is doing. So if you moved your distributer X degrees both the trailing and the leading changed.
By static you mean locking the distributor? If you just want to limit the amount of advance you can dick with the advancer spring in the distributer, and the slots the advancer moves in. It will limit the amount of advance when the engine hits higher RPMs.
To put the distributor in the front cover...
take the cap off of the distributer.
line up the marks on the shaft
rotate the engine to TDC
shove the cap less distributer into the front cover
then twist the distributer until the pickup coil for the leading ignition moves over the sending unit for the leading ignition.
EDIT: this will set the distributer up to fire as the factory suggests. If you want more or less advance instead of putting the engine on TDC move it to wherever and it will fire at that point in rotation.
By static you mean locking the distributor? If you just want to limit the amount of advance you can dick with the advancer spring in the distributer, and the slots the advancer moves in. It will limit the amount of advance when the engine hits higher RPMs.
To put the distributor in the front cover...
take the cap off of the distributer.
line up the marks on the shaft
rotate the engine to TDC
shove the cap less distributer into the front cover
then twist the distributer until the pickup coil for the leading ignition moves over the sending unit for the leading ignition.
EDIT: this will set the distributer up to fire as the factory suggests. If you want more or less advance instead of putting the engine on TDC move it to wherever and it will fire at that point in rotation.
#6
Yes I understand that but I can't even get it to start. As I understand is that bridge port should have around 24 and 5 btdc leading and trailing respectively at 6k. So from what your saying is no matter what I should always put it at tdc, line up the dimple and there should be enough adjustment in the dizzy to get to 24 deg?
#7
So this is a fresh build? Or did you just pull the distributer to make a change?
If its a fresh build I'd just get the thing to run as per factory recommendations first. Then start to worry about 6k revs.
I gotta say I'm no scientist when it comes to timing. I know I should be better but as long as I don't hear any pinging or nocking sounds and the engine sounds happy I'm pretty good with it. I also check my plugs on a regular for denotation. BUT I do think you can get less than 10 degrees out of moving the distributer when its sitting on the front cover.
If its a fresh build I'd just get the thing to run as per factory recommendations first. Then start to worry about 6k revs.
I gotta say I'm no scientist when it comes to timing. I know I should be better but as long as I don't hear any pinging or nocking sounds and the engine sounds happy I'm pretty good with it. I also check my plugs on a regular for denotation. BUT I do think you can get less than 10 degrees out of moving the distributer when its sitting on the front cover.
Last edited by Qingdao; 05-08-16 at 12:05 AM. Reason: RX7 Club doesn't like less than signs.
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#8
So this is a fresh build? Or did you just pull the distributer to make a change?
If its a fresh build I'd just get the thing to run as per factory recommendations first. Then start to worry about 6k revs.
I gotta say I'm no scientist when it comes to timing. I know I should be better but as long as I don't hear any pinging or nocking sounds and the engine sounds happy I'm pretty good with it. I also check my plugs on a regular for denotation. BUT I do think you can get less than 10 degrees out of moving the distributer when its sitting on the front cover.
If its a fresh build I'd just get the thing to run as per factory recommendations first. Then start to worry about 6k revs.
I gotta say I'm no scientist when it comes to timing. I know I should be better but as long as I don't hear any pinging or nocking sounds and the engine sounds happy I'm pretty good with it. I also check my plugs on a regular for denotation. BUT I do think you can get less than 10 degrees out of moving the distributer when its sitting on the front cover.
#12
RX for fun
iTrader: (13)
Make sure youre on TDC (search under my SN for flywheel trick) then install the dizzy (dimple on the gear is in line with the notch on dizzy shaft housing). Since its got to be flooded by now, pour 2 cap full through the carb or squirt some engine oil thru spark plug holes, handcrank the motor thru main pulley bolt a few times. Install new or clean/dry plugs and fully charged battery. Then it should start provided you have good igniters. Once its idling, loosen the 10mm hold down nut (this is your leading timing) and the 2 scews on the diapram facing the rear (trailing), rev to 6k and set the leading timing.
#13
Make sure youre on TDC (search under my SN for flywheel trick) then install the dizzy (dimple on the gear is in line with the notch on dizzy shaft housing). Since its got to be flooded by now, pour 2 cap full through the carb or squirt some engine oil thru spark plug holes, handcrank the motor thru main pulley bolt a few times. Install new or clean/dry plugs and fully charged battery. Then it should start provided you have good igniters. Once its idling, loosen the 10mm hold down nut (this is your leading timing) and the 2 scews on the diapram facing the rear (trailing), rev to 6k and set the leading timing.
#14
Here is another video after trying to start after bringing the timing back to stock.
The pictures show how i set the timing. Let me know if i did something wrong.
Lined it up at TDC with the yellow mark
Checked the rear counterweight thru the flywheel inspection port
took out distributor and lined up the notch to the dimple.
Picture of the rotor after installation
If anyone can take a look and let me know if it all looks ok.
Also, when i unplugged the injector trying to deflood after a whole lot of cranking it sounded like it wanted to start, so it might be flooding.
Table from Aaron cakes write up. I changed the rpm and the fuel load from 0 to 100 because it was in the 200's so i thought to change it. Also increased 20% from aarons original values and also tried his original values.
The pictures show how i set the timing. Let me know if i did something wrong.
Lined it up at TDC with the yellow mark
Checked the rear counterweight thru the flywheel inspection port
took out distributor and lined up the notch to the dimple.
Picture of the rotor after installation
If anyone can take a look and let me know if it all looks ok.
Also, when i unplugged the injector trying to deflood after a whole lot of cranking it sounded like it wanted to start, so it might be flooding.
Table from Aaron cakes write up. I changed the rpm and the fuel load from 0 to 100 because it was in the 200's so i thought to change it. Also increased 20% from aarons original values and also tried his original values.
#18
Ill bring in the split in.
With the gear, i thought, it did not matter. I drew it out and no matter what way you out it it always spun the teeth the same way, but maybe i am just going crazy.
When i spin the engine clockwise when looking at it from the front, what way is the dizzy rotor supposed to spin? clockwise or anticlockwise? If it spins the opposite way then clearly i screwed up and mounted the gear backwards.
#19
Lapping = Fapping
iTrader: (13)
Um, that's not how it works. You must be going crazy. The dizzy will always turn the same direction regardless of installed gear direction. The thing you need to know about it is the teeth are a little offset so if the gear is on backwards, it will require the dizzy body to be rotated a lot just to get the pickup's core to align with one of the two correct reluctor tips. The dizzy turns counterclockwise and at half e-shaft speed, thus two reluctor tips out of the four will work (the tips that are under the leading part of the rotor are the ones to use, as looks correct in your pic).
I don't know if I just confused you.
I don't know if I just confused you.
#20
Um, that's not how it works. You must be going crazy. The dizzy will always turn the same direction regardless of installed gear direction. The thing you need to know about it is the teeth are a little offset so if the gear is on backwards, it will require the dizzy body to be rotated a lot just to get the pickup's core to align with one of the two correct reluctor tips. The dizzy turns counterclockwise and at half e-shaft speed, thus two reluctor tips out of the four will work (the tips that are under the leading part of the rotor are the ones to use, as looks correct in your pic).
I don't know if I just confused you.
I don't know if I just confused you.
I guess i am not going crazy since the dizzy will always spin regardless of direction.
How do i insure or check that the gear was installed correctly? So to understand correctly, the gear teeth have an offset that would screw up timing if installed backwards?
#21
Lapping = Fapping
iTrader: (13)
Think of it this way. If you just can't get the dizzy "stabbed" correctly so that it lines up right for static timing, chances are your dizzy drive gear was installed backwards on the e-shaft. There is no fix for this other than to dig way back into the engine to flip it around, but you need to be 100% sure it is on backwards. Otherwise it's a lot of work down the drain.
The only work around I know of it to rotate the dizzy housing until the reluctor tip is aligned with the leading pickup core. You can stab the dizzy multiple times, trying all the tooth angle meshings possible, until you find something that will allow the tip and core to be as close together as possible. I think the slot in the steel baseplate is wide enough that this might be possible without having to resort to cutting or grinding it out longer or wider.
Does what I just said make a little more sense?
The only work around I know of it to rotate the dizzy housing until the reluctor tip is aligned with the leading pickup core. You can stab the dizzy multiple times, trying all the tooth angle meshings possible, until you find something that will allow the tip and core to be as close together as possible. I think the slot in the steel baseplate is wide enough that this might be possible without having to resort to cutting or grinding it out longer or wider.
Does what I just said make a little more sense?
#22
Lapping = Fapping
iTrader: (13)
Looking at your pic, it looks like if you rotate the dizzy housing clockwise as far as it will go so it will butt up against the hold down bolt, you just might be able to get the reluctor tip to point right at the leading pickup's core. Try this and report back.
If this works, chances are your dizzy drive gear was installed backwards.
If this works, chances are your dizzy drive gear was installed backwards.
#23
Looking at your pic, it looks like if you rotate the dizzy housing clockwise as far as it will go so it will butt up against the hold down bolt, you just might be able to get the reluctor tip to point right at the leading pickup's core. Try this and report back.
If this works, chances are your dizzy drive gear was installed backwards.
If this works, chances are your dizzy drive gear was installed backwards.
Think of it this way. If you just can't get the dizzy "stabbed" correctly so that it lines up right for static timing, chances are your dizzy drive gear was installed backwards on the e-shaft. There is no fix for this other than to dig way back into the engine to flip it around, but you need to be 100% sure it is on backwards. Otherwise it's a lot of work down the drain.
The only work around I know of it to rotate the dizzy housing until the reluctor tip is aligned with the leading pickup core. You can stab the dizzy multiple times, trying all the tooth angle meshings possible, until you find something that will allow the tip and core to be as close together as possible. I think the slot in the steel baseplate is wide enough that this might be possible without having to resort to cutting or grinding it out longer or wider.
Does what I just said make a little more sense?
The only work around I know of it to rotate the dizzy housing until the reluctor tip is aligned with the leading pickup core. You can stab the dizzy multiple times, trying all the tooth angle meshings possible, until you find something that will allow the tip and core to be as close together as possible. I think the slot in the steel baseplate is wide enough that this might be possible without having to resort to cutting or grinding it out longer or wider.
Does what I just said make a little more sense?
#24
I have to rotate the distributor counterclockwise even past the slot to get it to align
I have to rotate the distibutor clockwise all the way and it still does not completely align.
It feels like on one teeth i have to turn it all the way to one side to get it to align and if i put it on thee next teeth over i have to turn it the other way to get it to align. So does this mean i have my gear on backwards? I really hope not, its a pain in the *** to flip it.