Injector Upgrade? Old Stock Injectors vs Newer Variants?
12-28-10, 01:57 PM
#1
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Injector Upgrade? Old Stock Injectors vs Newer Variants?
So I was considering upgrading my current injectors to the current injectors, mainly on the basis of what I was reading in a thread.
https://www.rx7club.com/power-fc-forum-47/obsolete-injectors-927585/
The idea behind this is upgrading the stock injectors to a new style of injectors such as Bosch EV14 500cc injectors, I didn't see any injector sizes that were the specific output for turbo or NA.
So below are my thoughts and ideas.
So "say" I decided to upgrade my stock injectors on my 13 6-port to the Bosch EV-14 - 500cc injectors all around. Considering the spray pattern is far better at atomization, would this equate to more more power? Or could this be that since atomization is better, I could use less fuel, get the same power, and still have a very stable engine?
And since these are considerable better injectors then stock ones, would these also be good for stock turbo charging fuel requirements, say an Series 4 turbo charger bolted onto a 6-port at stock boost levels?
Thoughts and feedback please.
https://www.rx7club.com/power-fc-forum-47/obsolete-injectors-927585/
The idea behind this is upgrading the stock injectors to a new style of injectors such as Bosch EV14 500cc injectors, I didn't see any injector sizes that were the specific output for turbo or NA.
So below are my thoughts and ideas.
So "say" I decided to upgrade my stock injectors on my 13 6-port to the Bosch EV-14 - 500cc injectors all around. Considering the spray pattern is far better at atomization, would this equate to more more power? Or could this be that since atomization is better, I could use less fuel, get the same power, and still have a very stable engine?
And since these are considerable better injectors then stock ones, would these also be good for stock turbo charging fuel requirements, say an Series 4 turbo charger bolted onto a 6-port at stock boost levels?
Thoughts and feedback please.
12-28-10, 02:43 PM
#2
well if you still got the stock air box, im sure if you go intake and help the car breath better it may see better optimization. If all stock, i cant imagine much since cfm would still be the same. But i do see the interest in this since the newer design injectors would be overall better designed than the old technology.
12-28-10, 03:15 PM
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you do know that bosch style injectors dont work with the stock fuel rails right??
bosch style is 14mm o-ring
stock denso style is 11mm o-ring
so you would need to get the injectors machined or get aftermarket fuelrails like KG
bosch style also uses the EV1 connectors, different then stock
bosch style is 14mm o-ring
stock denso style is 11mm o-ring
so you would need to get the injectors machined or get aftermarket fuelrails like KG
bosch style also uses the EV1 connectors, different then stock
12-28-10, 03:26 PM
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you do know that bosch style injectors dont work with the stock fuel rails right??
bosch style is 14mm o-ring
stock denso style is 11mm o-ring
so you would need to get the injectors machined or get aftermarket fuelrails like KG
bosch style also uses the EV1 connectors, different then stock
bosch style is 14mm o-ring
stock denso style is 11mm o-ring
so you would need to get the injectors machined or get aftermarket fuelrails like KG
bosch style also uses the EV1 connectors, different then stock
12-28-10, 03:39 PM
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I assume that the injectors that are made these days such as Bosch EV-14s are far better at atomizing fuel better than what I have stock anyways.
My assumption is that if you have better atomization, the more fuel will get burned, increasing power, or if you like, you can decrease the amount of fuel being sprayed which can decrease fuel consumption. I'm not sure if my assumptions are correct which is why I'm asking for more information about stock fuel injectors and current fuel injector standards in newer cars.
12-28-10, 03:40 PM
#7
injector technology hasn't changed much in 20 years AFAIK. You might see an increase in HP if your current injectors are clogged or failing. But it would be minimal. And most likely un-detected by the butt dyno.
If you plan on running boost later on, you'll need injectors larger than 500's anyway. So that point is sort of moot..
If you plan on running boost later on, you'll need injectors larger than 500's anyway. So that point is sort of moot..
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12-28-10, 03:49 PM
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injector technology hasn't changed much in 20 years AFAIK. You might see an increase in HP if your current injectors are clogged or failing. But it would be minimal. And most likely un-detected by the butt dyno.
If you plan on running boost later on, you'll need injectors larger than 500's anyway. So that point is sort of moot..
If you plan on running boost later on, you'll need injectors larger than 500's anyway. So that point is sort of moot..
12-28-10, 05:27 PM
#9
so you would need to get the injectors machined or get aftermarket fuelrails like KG
bosch style also uses the EV1 connectors, different then stock
from a practical perspective though, if you don't need a size bigger than stock (and you don't want to have to deal with tuning hassles) then it may not be worth the money and trouble
12-28-10, 05:53 PM
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Injector Dynamics have ones that will fit. 100% sure, I have discussed it with them. The blue injectors have 11mm top o-rings, and there is a part you can install to make them fit at the bottom without leaks. I'm not sure if any of the other EV14 vendors sell ones that will fit.
so you would need to get the injectors machined or get aftermarket fuelrails like KG
The EV14 injectors don't use EV1 connectors. They use EV6 connectors depending on which ones you buy. And the 86-87 1/2 harnesses and injectors use straight up EV1 connectors, with a center tab like every EV1 but later models are different. I have Bosch EV1 injectors plugged into my stock 87 harness right now.
Yes, the technology has improved a lot. The valves and solenoid coils are much smaller, the spray pattern is improved, and newer injectors can run at higher pressures. Have you ever looked at pictures of Rx-8 injectors? They are a much newer style.
from a practical perspective though, if you don't need a size bigger than stock (and you don't want to have to deal with tuning hassles) then it may not be worth the money and trouble
so you would need to get the injectors machined or get aftermarket fuelrails like KG
The EV14 injectors don't use EV1 connectors. They use EV6 connectors depending on which ones you buy. And the 86-87 1/2 harnesses and injectors use straight up EV1 connectors, with a center tab like every EV1 but later models are different. I have Bosch EV1 injectors plugged into my stock 87 harness right now.
Yes, the technology has improved a lot. The valves and solenoid coils are much smaller, the spray pattern is improved, and newer injectors can run at higher pressures. Have you ever looked at pictures of Rx-8 injectors? They are a much newer style.
from a practical perspective though, if you don't need a size bigger than stock (and you don't want to have to deal with tuning hassles) then it may not be worth the money and trouble
According to the guy I talked to, the ID725 injectors are linear all the way down to 15cc which is nuts.
So it seems like I would need a proper injector that is as close to 550cc, that is as good as the Injector Dynamic Injectors as possible.
On the subject of RX8 Injectors, I was looking for the size of those injectors, and from what I could find out was that they are 330cc. Considering these are smaller injectors, the engine is higher compression and makes more power. It would seem that atomization would play good part in fuel efficiency and power.
12-28-10, 07:02 PM
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I was mistaken on injector size of the RX8. A 2009 RX8 has 390cc and 480cc, It is still over all a lower flow output than the stock injector size of a 2nd generation non-turbo RX7.
12-28-10, 07:23 PM
#12
series 1 Rx-8 has 6 injectors, series 2 has 4 like the older engines. the Rx-8 fuel injection system is much better optimized for emissions and fuel economy than the FC. As I said before it uses higher fuel pressure and it doesn't have the injector mixing plate sockets. The injector atomization system is far superior. They call it the "jet air" mixing system because of the fast stream of fresh air that flows along the floor of the intake port runner.
12-28-10, 07:53 PM
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series 1 Rx-8 has 6 injectors, series 2 has 4 like the older engines. the Rx-8 fuel injection system is much better optimized for emissions and fuel economy than the FC. As I said before it uses higher fuel pressure and it doesn't have the injector mixing plate sockets. The injector atomization system is far superior. They call it the "jet air" mixing system because of the fast stream of fresh air that flows along the floor of the intake port runner.
Would it be possible to fit RX8 Injectors to the RX7 S4 motor? Also would you have more information on the fuel atomization system of the 13B RENESIS? My curiosity is peaked right now on this concept. I have a think about maximizing the potential of an engine, even if it is an older design.
12-28-10, 08:13 PM
#14
There's a reason why everybody just gets the factory injectors cleaned on the nonturbos. It doesn't make financial sense to do otherwise. Now you say you might turbo the engine later, but your biggest limit is engine management. Using a T2 Rtek 2.1 would be fine if you want to get a set of four 725cc EV14 injectors (Injector Dynamics or whatever). Those are the two options I would try if I were you.
I am of the same mentality in the sense that it's frustrating having a car so old without modern injectors, electronic throttle, a proper MAF sensor instead of a flapper AFM, etc. But there's no point in trying to make the car something it's not, which is why I suggest you either stay stock or do 4 ID725 injectors and use the 720/720 preset on the turbo engine Rtek 2.1 .
There's a good chance they have the same upper and lower bore dimensions. The tops certainly look the same at least (typical 11mm Japanese style). I am unsure if the height would be an issue.
Yes.
Note that the Rx-8 can idle at a proper 14.7:1 unlike the older rotaries with peripheral exhaust ports. This is because the side exhaust ports with resulting lack of overlap between the intake and exhaust strokes reduces the amount of internal exhaust gas recirculation. The reduced EGR increases combustion stability and allows the Renesis to idle leaner.
I am of the same mentality in the sense that it's frustrating having a car so old without modern injectors, electronic throttle, a proper MAF sensor instead of a flapper AFM, etc. But there's no point in trying to make the car something it's not, which is why I suggest you either stay stock or do 4 ID725 injectors and use the 720/720 preset on the turbo engine Rtek 2.1 .
Originally Posted by Gryffinwings
Would it be possible to fit RX8 Injectors to the RX7 S4 motor?
Also would you have more information on the fuel atomization system of the 13B RENESIS?
Note that the Rx-8 can idle at a proper 14.7:1 unlike the older rotaries with peripheral exhaust ports. This is because the side exhaust ports with resulting lack of overlap between the intake and exhaust strokes reduces the amount of internal exhaust gas recirculation. The reduced EGR increases combustion stability and allows the Renesis to idle leaner.
12-28-10, 08:29 PM
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There's a reason why everybody just gets the factory injectors cleaned on the nonturbos. It doesn't make financial sense to do otherwise. Now you say you might turbo the engine later, but your biggest limit is engine management. Using a T2 Rtek 2.1 would be fine if you want to get a set of four 725cc EV14 injectors (Injector Dynamics or whatever). Those are the two options I would try if I were you.
I am of the same mentality in the sense that it's frustrating having a car so old without modern injectors, electronic throttle, a proper MAF sensor instead of a flapper AFM, etc. But there's no point in trying to make the car something it's not, which is why I suggest you either stay stock or do 4 ID725 injectors and use the 720/720 preset on the turbo engine Rtek 2.1 .
There's a good chance they have the same upper and lower bore dimensions. The tops certainly look the same at least (typical 11mm Japanese style). I am unsure if the height would be an issue.
Yes.
Note that the Rx-8 can idle at a proper 14.7:1 unlike the older rotaries with peripheral exhaust ports. This is because the side exhaust ports with resulting lack of overlap between the intake and exhaust strokes reduces the amount of internal exhaust gas recirculation. The reduced EGR increases combustion stability and allows the Renesis to idle leaner.
I am of the same mentality in the sense that it's frustrating having a car so old without modern injectors, electronic throttle, a proper MAF sensor instead of a flapper AFM, etc. But there's no point in trying to make the car something it's not, which is why I suggest you either stay stock or do 4 ID725 injectors and use the 720/720 preset on the turbo engine Rtek 2.1 .
There's a good chance they have the same upper and lower bore dimensions. The tops certainly look the same at least (typical 11mm Japanese style). I am unsure if the height would be an issue.
Yes.
Note that the Rx-8 can idle at a proper 14.7:1 unlike the older rotaries with peripheral exhaust ports. This is because the side exhaust ports with resulting lack of overlap between the intake and exhaust strokes reduces the amount of internal exhaust gas recirculation. The reduced EGR increases combustion stability and allows the Renesis to idle leaner.
What are the stock dimensions of the RX7 FC injectors? I believe you said the connector is an EV1 connection. What is the FC design based on? Is it the EV1 design?
12-28-10, 10:08 PM
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Also do you have the over all length of the S4 injector?
Also these questions are still to be answered:
What is the FC design based on? Is it the EV1 design?
Also if anyone has the all the dimensions of the RX8 injectors that would be great.
12-28-10, 10:43 PM
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That is really helpful, now only if I could get the same info for the RX8 Injectors I'd be great. So far all I've got are pictures, haven't been able to find specific info:
http://www.fiveomotorsport.com/fuel-...rs/mazda/rx-8/
http://www.fiveomotorsport.com/fuel-...rs/mazda/rx-8/
12-28-10, 10:53 PM
#21
i should state, i think these would be generic, so im not sure. they could be, could be close, and could be completly off. so who knows.
Injector Length: Overall; 3-0 inches, o-ring to o-ring: 2-1/2 inches, 64.5 mm
Injector diameter: 16 mm
O-rings: Top and bottom, Viton, 12mm and 16 mm
from
http://www.fiveomotorsport.com/impor...s/?itemid=1213
Injector Length: Overall; 3-0 inches, o-ring to o-ring: 2-1/2 inches, 64.5 mm
Injector diameter: 16 mm
O-rings: Top and bottom, Viton, 12mm and 16 mm
from
http://www.fiveomotorsport.com/impor...s/?itemid=1213
12-28-10, 10:57 PM
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I have a strong feeling that those RX8 injectors are almost plug and play for FCs, I'm quite tempted to try it, the following link suggest that might be the case:
The guy also says the following:
"I played with some different injector sizes/designs to see what I liked here. These are all used, so not cleaned and the likes, which I'd recommend before use. There is a set of four (4) of RX-7 460's, four (4) Rx-8 440cc Injs, and Four (4) RC 550's Low Impedence with splice in clips."
http://www.miataturbo.net/showthread.php?t=52642
http://img.photobucket.com/albums/v2...1/IMG_1037.jpg
The guy also says the following:
"I played with some different injector sizes/designs to see what I liked here. These are all used, so not cleaned and the likes, which I'd recommend before use. There is a set of four (4) of RX-7 460's, four (4) Rx-8 440cc Injs, and Four (4) RC 550's Low Impedence with splice in clips."
http://www.miataturbo.net/showthread.php?t=52642
http://img.photobucket.com/albums/v2...1/IMG_1037.jpg
12-28-10, 11:26 PM
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Interestingly enough I found more info regarding this. Mind you this is plug n play injectors for the Mazda Miata, which states that the FC RX7 injectors are plug and play. However since the guy that was experimenting with also with RX8 injectors, I'm going to assume that the injectors will fit physically, but will require a patch in harness to work electrically, I'm quite tempted to buy a set and try this out. But I will need some kind of way to hook them up. I'm thinking RX8 injectors are in my future, just need to find the right ones.
http://miataturbo.wikidot.com/fuel-injectors
http://miataturbo.wikidot.com/fuel-injectors
12-28-10, 11:36 PM
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Sorry I'm posting more links for the RX7 injector to RX8 injector swap, but I keep finding more information that makes it seem like they are interchangeable.
http://forum.miata.net/vb/showthread.php?t=209916
http://forum.miata.net/vb/showthread.php?t=209916
12-28-10, 11:51 PM
#25
The FC injectors are made by Denso. Denso is a spinoff of Toyota. Denso licensed/licenses a lot of technology from Bosch. This image is off the ID website:
Look familiar? The EV1 looks a lot like the FB/FC injectors and the EV6/EV14 look a lot like the Rx-8 injectors. The more you work on different cars the more you realize how much technology from a given era is shared and/or copied. The entire fuel injection system in Rx-7's are based off Bosch L-Jetronic/Motronic (airflow-based) for the FC and Bosch D-Jetronic (pressure-based) for the FD. The L-Jetronic system was first offered in Porsche 924's and the D-Jetronic system was in Porsche 914's.