How Does Vacuum Advance Work? 12A - 13B Mazda RX7 Distributors
ฝัง
- เผยแพร่เมื่อ 7 ก.ย. 2024
- Did some research for you guys and made a video explaining the differences between the RX7 Distributors, as well as help to clarify how the vacuum and mechanical advances work in the distributor. Comment Below with any questions. This stuff can be confusing!!
Join us on Patreon!
/ radpotential
Just a small correction brother, the SA 1980 distributor cap and rotor button is the same as the 81-85 model. The igniters are J106 models.
Really!!!! Thats awesome!! Ill pin your comment. Thank you so much. It was been a minute since I had the 1980 dizzy in front of me. Last time I'd have seen it was when I removed it from my 1980 lol!!!
if you run trailing timing close to the leading timing so the ignition event happens almost on top of each other with no gap, gets you a little cleaner smelling exhaust and a smidge more throttle response.
Great video as usual. A NZ rotar tip I was told is to remove the metal cover under the dizzy as helps disapate heat, maybe make the ignition modules last longer.
I needed this I'm going carb on my fc and I'm tryna figure everything with it out so I appreciate it, I'm new to carb stuff and this was great
Love the vid! Would like a bit more explanation about why/when to lock the centrifugal advance and how you decide wether to run the vacuum advance.
I'll have to do some digging and testing on running a locked distributor. I have never messed with it before. But I know some folks who have. It's on the list!!!
@@RADPotential I'm likely going to be running a locked distributor for my 12a turbo engine. Mainly trying to prevent advance under boost.
I know im late to the party, but Thank you for your knowledge!!
Awesome video man all the information we could need.
Love the content! That was very helpful and informational
I needed this!
Your the man! Thanks for making these videos!!
You got it man!!
Wouldn’t you want to hook up the pots to ported vacuum rather than manifold vacuum. Because if it’s hooked up to manifold then they would advanced the whole time, right?
as soon as your carburetor or throttle body is opened past maybe 10 or 15% there is no vacuum anymore. there is suction obviously, it's sucking in air and fuel. but the vacuum at idle is about 20-25 inches and once the throttle plate is opened past tip in, the vacuum drops to 0-2 inches. Not enough to move the dash pots on these dizzys.
I have a type 3 Distuributor and a Type 2 . The type 3 is the one that I am running. but the type 3 has the right area of timing between the gears without enough rotation in the distributor to get to the right timing in the right area. Using a vacuum pump advance the timing after starting. but trying several options without great result. Does not advance the 15 degrees that the book says it should. I tried a MSD 6 A _2 digital that should have a computer timing delay , but neither MSDF 6 box works with this engine. Any suggestions besides enlarging the adjustment hole.
I’ve got a sniper and it showed my timing bouncing from 15-36 degrees at idle why lol help it’s a full bridge 12a
When you say "more timing" you actually mean more advance on the timing, a small point, I think everyone knows what you mean. I have a stock 79 sa, I don't see any point in changing distributors because I had so many problems with the igniters on my 84. was stranded many times when they failed, and had to carry a spare with me. yeah, points wear and that throws off the timing, but it was the standard for a lot of years.
also for beginners that might not know what you're talking about you could maybe explain the terms: (spark) timing, TDC, BTDC,... as they relate to rotaries and performance
Thank you good sir
Great video man!
When you set your timing at idle is that with vacuum advance pods hooked up? Thanks for the great videos!
I set the timing with the pots disconnected at idle. You can anticipate the built in advances to add 10 degrees of timing from whatever that base number is.
@@RADPotential thank you, that will help! I currently have it set to zero degrees at idle with vacuum advance pots hooked directly to manifold, no rats nest.
Advantages/Disadvantages of running zero split on leading/trailing? Im running it with an MSD on my 80. Still havent got the car to run to be drivable so I cant tell a difference lol.
I can ask my Tuner friends and see what their thoughts are. I have heard of that in the boosted world. But I can't remember if it's a common practice or not. Or the benefits
Much appreciated. Main reason I did it was so I didnt have to run a second MSD box. Doubt itll make any power as im running a nikki and stock port for now.
my streetport 12A does that missing and bad fuel economy thing, but it ran like crap before I advanced the timing a bunch.
That's awesome!!! Plus a bit better top end pull??
@@RADPotential oh the top end is perfect. once the secondaries open up the car is absolutely incredible. It hits this harmonic frequency as it passes 7 grand that I can't put into words, it sounds like heaven.
@@RADPotential It's also a little tough to start cold, especially because I don't have the choke hooked up.
great video as always! Ive got a gsl-se with a deleted rats nest. It runs great with vacuum advance pots disconnected and vacuum open to air. When I plug the vac port it idles too low and stalls, when i connect the vac pots it revs up to 3k on its own and doesnt respond. any thoughts?
you've got a whole different conversation of problems there. did you ever square it all out and get it running properly? best of luck.
@@perjian1697 I did, it came down to about 5 little things(mostly vacuum related). For clarification, I was finishing up swapping the SE motor into a GS. Rats nest had been deleted by the previous owner of the SE but the car ran great before i pulled the motor.
Do you know why there would be coolant on top of the engine? I have to keep refilling coolant from time to time.
Leaking between the intake and the block, 12a.... or leaking from the back of the water pump, or leaking from the throttle body....13b
Looking for someone to work on my 1990 Rx7 gtu 13b not turbo in Peoria il. Just moved here can you help.
Phalanx performance in STL
@@RADPotential Thank you
I have a 82 and I can't get it to stay running! Rebuilt the carb new fuel pump n filter! It starts and runs for a minute or two and then just drops in rpm an kills any help/advise?
Is it flooding?? Can you see fuel dripping out of the venturis while it's just idling?
Is there any websites that sell exterior parts for these cars like fenders and taillights?
Not really. There isn't a big aftermarket for these cars at all.
@@RADPotential yeah I haven’t been able to find much I figured about the only way would be to find a parts car