Fuel Injection Question
02-28-08, 10:24 AM
#1
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Fuel Injection Question
2 questions..
Servicing my injectors this morning, and curious about the balance of the flow rates.. First number is Static flow rate, second is dynamic (75% Duty Cycle)
My Primaries: 470cc/350cc 477cc/347cc
My Secondaries:459cc /331cc 455cc/333cc
In a piston engine, it is ideal for the injectors to be balanced at least within approx 2%, depending on size, since you have primaries and secondaries, do they all need to be balanced together, or do they just need to be balanced with the other primary/secondary? feel Really stupid for asking this question because this is what i do for a living, but we dont do much rotory stuff, and this is my car
?#2
I read that 88 and up have high impedance injectors.. well i have an 88, checked VIN on firewall with title, and have low impedance injectors.. Red w/ bosch style clips.. i cant guarantee it, but i was told this was the orignial motor.. any ideas?
I would also like to comment on the benefit of having your injectors serviced if your having problems with them, not just going out and buying a new set.. my filters were nasty, and the pintle caps were cracked and covered in some rather nasty gunk, the preflow rates (before i cleaned them), were about 20-25cc lower than after, i wish i had saved the numbers, and 3 of them were leaking. After cleaning the spray patterns were perfect, no leakers and the rates were much better..
Servicing my injectors this morning, and curious about the balance of the flow rates.. First number is Static flow rate, second is dynamic (75% Duty Cycle)
My Primaries: 470cc/350cc 477cc/347cc
My Secondaries:459cc /331cc 455cc/333cc
In a piston engine, it is ideal for the injectors to be balanced at least within approx 2%, depending on size, since you have primaries and secondaries, do they all need to be balanced together, or do they just need to be balanced with the other primary/secondary? feel Really stupid for asking this question because this is what i do for a living, but we dont do much rotory stuff, and this is my car
?#2
I read that 88 and up have high impedance injectors.. well i have an 88, checked VIN on firewall with title, and have low impedance injectors.. Red w/ bosch style clips.. i cant guarantee it, but i was told this was the orignial motor.. any ideas?
I would also like to comment on the benefit of having your injectors serviced if your having problems with them, not just going out and buying a new set.. my filters were nasty, and the pintle caps were cracked and covered in some rather nasty gunk, the preflow rates (before i cleaned them), were about 20-25cc lower than after, i wish i had saved the numbers, and 3 of them were leaking. After cleaning the spray patterns were perfect, no leakers and the rates were much better..
Last edited by AnarchyFC; 02-28-08 at 10:36 AM.
02-29-08, 07:11 AM
#3
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I'd like to know the answer to #1 as well, so even though I don't know this brings you back to the top.
On #2, read this page if you haven't... http://www.rotaryresurrection.com/2n...ctor_info.html - it's not an answer to why on your problem but may give some leads. I doubt someone changed the wiring harness in your car. The only thing I could think of, and this is pure speculation, is that the change from low to high impedance injectors by Mazda was not done exactly at model year change. Since the difference between 86/87 and 88 is minor, perhaps the early build 88 models still had low imp. injectors. The real changes did not come until the 89 model. I'd be curious on the build date of your car. Again, this is just a wild guess based on no fact... just what I know from other car manufacturers.
On #2, read this page if you haven't... http://www.rotaryresurrection.com/2n...ctor_info.html - it's not an answer to why on your problem but may give some leads. I doubt someone changed the wiring harness in your car. The only thing I could think of, and this is pure speculation, is that the change from low to high impedance injectors by Mazda was not done exactly at model year change. Since the difference between 86/87 and 88 is minor, perhaps the early build 88 models still had low imp. injectors. The real changes did not come until the 89 model. I'd be curious on the build date of your car. Again, this is just a wild guess based on no fact... just what I know from other car manufacturers.
02-29-08, 07:34 AM
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theres lots of things different between an early 88 and a late 88,
so many i can't even list, it's all little things, even the dash is made of different plastic, my original late 88 dash was made of black plastic under blue vinyl, the dash i just installed is tan plastic under gray vinyl cars vin sticker said like feb or march 88.
the windshield wiper switch plastic has a different texture and pattern on it.
injectors can be different,
some had aluminum hoods others didn't
slope on the idiot light/Clock and cover panel can be different angles,
some door locks have little black covers over where the key goes in ( looks
really nice) others don't.
for some reason mazda decided to change things somewhere between late 87 early 88 for the last year of the S4
so many i can't even list, it's all little things, even the dash is made of different plastic, my original late 88 dash was made of black plastic under blue vinyl, the dash i just installed is tan plastic under gray vinyl cars vin sticker said like feb or march 88.
the windshield wiper switch plastic has a different texture and pattern on it.
injectors can be different,
some had aluminum hoods others didn't
slope on the idiot light/Clock and cover panel can be different angles,
some door locks have little black covers over where the key goes in ( looks
really nice) others don't.
for some reason mazda decided to change things somewhere between late 87 early 88 for the last year of the S4
02-29-08, 01:57 PM
#5
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well.. guess regardless im gonna use a matched set.. i have 10 extra injectors, so, ill pull the best set.. i really wanna know for future reference.. if we get an RX-7 service in, i wanna be sure..
guess i need to throw em back in and start her up
guess i need to throw em back in and start her up
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