Locking the distributor for turbo
07-02-10, 11:10 PM
#1
35r 13b first gen
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Locking the distributor for turbo
I am a bit unsure of where im supposed to align the marks inside the distributor when i tack weld it to lock it. I know there are little hash marks that look like they are indicating degrees or whatnot. do i align them center to center of leadind and trailing? after i figure that out where do i tack the whole inside in relation to the distributor itself? thanks
07-04-10, 12:48 AM
#4
I would look in the 1st gen section. this may help some: https://www.rx7club.com/1st-generation-specific-1979-1985-18/how-lock-distributor-902792/
07-04-10, 06:20 PM
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35r 13b first gen
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they can move freely to any position you want when nothing is connected.. there isn't one position that they seem to stay at or want to rest at.
07-04-10, 09:09 PM
#7
Yeah, shutup kid.
You don't need to weld the weights, just remove the springs and they'll stay all the way out. If you want to weld them weld them all the way out so if the weld breaks it can't advance the timing any farther.
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07-05-10, 09:43 PM
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isnt the trailing supposed to be a certain degree off of the leading? that will change the position of the distributor for the same timing then. will the distributor need to me moved a tooth at all or will i still be able to get to the reccomended degre of advancement where its at. or am i way off and it doesnt advance that far?
07-06-10, 08:11 PM
#9
Yeah, shutup kid.
It's not enough of a timing difference to matter, just remove the springs, cap the vacuum ports, and set timing close to stock. The mechanical advance turns the rotor, so it doesn't affect leading/trailing split, I move trailing a few degrees closer to the leading.
07-18-10, 02:27 PM
#16
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ok, what you really need to do, if you haven't already, is figure out how the distributor actually works.
you'll notice please that there is a 4 tooth trigger wheel, and a leading pickup and a trailing pickup. the distributor, runs at half engine speed, so essentially 4 teeth = one trigger every 180 degrees.
the cap and rotor choose either rotor #1 or rotor #2.
the distributor (like almost all distributors) has mechanical advance and vacuum advance. these work independently of each other.
the vacuum advance is worth keeping, as when you are cruising you actually want it, and B it located the pickups, without it they can just flop around...
the mechanical advance, in a turbo car is the one that gets locked out. stock timing is like TDC at idle and advances to 20BTDC, which is more than we want, its much simpler to just eliminate the mechanical advance, and just run 10BTDC (just to pick a number) all the time
the simplest way to achieve this is just to remove the advance springs. this way instead of getting full advance by 3500rpm (or where ever) you get full advance as soon as the engine starts moving. its also easy to reverse, if you decided to join the 20th century.
there are other ways to do it, but then you have to pay attention to the alignment of the cap and rotor buttons, and the pickups and stuff.
with piston engines its really common to put different springs or change the amount of advance the distributor has, which is something the rotary people never do
you'll notice please that there is a 4 tooth trigger wheel, and a leading pickup and a trailing pickup. the distributor, runs at half engine speed, so essentially 4 teeth = one trigger every 180 degrees.
the cap and rotor choose either rotor #1 or rotor #2.
the distributor (like almost all distributors) has mechanical advance and vacuum advance. these work independently of each other.
the vacuum advance is worth keeping, as when you are cruising you actually want it, and B it located the pickups, without it they can just flop around...
the mechanical advance, in a turbo car is the one that gets locked out. stock timing is like TDC at idle and advances to 20BTDC, which is more than we want, its much simpler to just eliminate the mechanical advance, and just run 10BTDC (just to pick a number) all the time
the simplest way to achieve this is just to remove the advance springs. this way instead of getting full advance by 3500rpm (or where ever) you get full advance as soon as the engine starts moving. its also easy to reverse, if you decided to join the 20th century.
there are other ways to do it, but then you have to pay attention to the alignment of the cap and rotor buttons, and the pickups and stuff.
with piston engines its really common to put different springs or change the amount of advance the distributor has, which is something the rotary people never do
07-19-10, 11:24 AM
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ok so is 10 degrees separation good then or would like 12 or more be better?
thanks i really appreciate the help. im getting almost there. pretty soon i will actually be able to start it. then the real fun comes with tuning... no one seems to have experience tuning a turboed carbed rotary...
thanks i really appreciate the help. im getting almost there. pretty soon i will actually be able to start it. then the real fun comes with tuning... no one seems to have experience tuning a turboed carbed rotary...
07-20-10, 09:33 AM
#21
anywhere between 10 and 15 degrees should be ok. Technically you may make slightly less power with more separation between leading and trailing, but on any carb'd turbo setup I think goal #1 is to keep the motor together. As you're finding out, without computer controlled spark advance you have to make a lot of tradeoffs.
07-20-10, 11:16 AM
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Yeah i do see that now. I f would have known then what i know now i would have just went Fuel injection. Ho well theres always the future! Thank you very much for the advice!
07-20-10, 12:39 PM
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07-21-10, 01:27 PM
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