RX7 550cc injector question
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I'm installing my RX7 550cc injectors now to cure my n00b status. What do I need to put on the green tip to make these fit? Do I pull the black base off my stock purple 265cc injectors and put them on this? Or do I get some rubber gaskets from an auto shop?
i reused 3 of mine but i broke one and got a replacement at the local parts store. To be safe you should probably just replace all of them its not expensive. might be tough to find a place that has them though.
Just bring an injector with you, specify what car/year and I think they'd find it. I got mine serviced at DW and they replace all that stuff when doing service so I didn't have to buy em seperately.
The black lower seal pieces should just slide off the pintle caps. When I removed my stock injectors 2 of the 4 remained stuck in the runners so they can't be all that tight on the injectors.
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What parts do I replace exactly? There is the green pintle cap and the donut that goes around it. Am I just looking for the donut ring? I got the rings off the stock injectors, but 1 cracked. Gotta wait for the store to open tomorrow.
Look over the pintle caps and make sure there aren't any cracks. Make sure the top o-rings that seal into the fuel rail are in good shape. Make sure there isn't any gunk in the little filter baskets. All of that stuff including the lower seals gets replaced when you have a reputable company service your injectors BTW. But if all the little parts look good, you can run them and just pray that you don't have any weird spray patters or one injector flowing significantly different from the others.
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I spoke with the guy that is doing the injector testing and he doesn't have the injector insulators that I need. Can you guys tell me if this is what I want, and would I be ordering the 1999-2005 set? Do I have to replace the green pintle caps to those of the stock ones from my year?
Finish Line / Rosenthal Mazda Parts & Accessories :: Miata / MX-5 :: Engine :: Gaskets/Seals :: Injector Insulator Set
Finish Line / Rosenthal Mazda Parts & Accessories :: Miata / MX-5 :: Engine :: Gaskets/Seals :: Injector Insulator Set
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Alright, I was able to get them installed and engine running fairly well this morning, great success! I didn't take chances with the o-rings and isolators so I just purchased some Mazda parts. $35 well wasted.
Unfortunately I forgot to make sure the shop tested them for 3bar. They only tested them for 40psi and they all flowed 430cc....I guess that's ok for me and my setup either way. I'm not sure how much 3.5psi will change the volume.
My only concern is the pintle cap. These sit deeper into the intake manifold than the stock ones, or the RC 550cc injectors I've seen. Does this cause any issue?
Unfortunately I forgot to make sure the shop tested them for 3bar. They only tested them for 40psi and they all flowed 430cc....I guess that's ok for me and my setup either way. I'm not sure how much 3.5psi will change the volume.
My only concern is the pintle cap. These sit deeper into the intake manifold than the stock ones, or the RC 550cc injectors I've seen. Does this cause any issue?
shouldnt cause an issue! plenty of people on here run RX-7 injectors without issue. i installed a set of 320cc RX-7 injectors into a friends car the other weekend and the tip sits deeper that the OEM injectors like yours do and his car has no problems.
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Thanks, I was just concerned that I didn't purchase the right isolator or something.
I used the isolators, o-rings, and upper grommet listed for the NB in the parts catalogue if any other n00bs come across this thread.
Part #
Top Grommet 8574-13-252
O-Ring 8574-13-253
Insulator 8574-13-257
I used the isolators, o-rings, and upper grommet listed for the NB in the parts catalogue if any other n00bs come across this thread.
Part #
Top Grommet 8574-13-252
O-Ring 8574-13-253
Insulator 8574-13-257






