gdub29e

iTrader: (16)

I’m definitely not pissing at ya. This is why I hesitate to post with any frequency because it always turns into a debate. I agree with you that your way is a great way . I just don’t agree that it’s the correct way for everyone. I remember when they were doing these 15 some years ago. There was definitely a few people that had problems. Having said that I myself have experienced an ID 2200 injector fail but I think it’s a rare experience so I didn’t mention it earlier.

They’ve come down in price. That’s great! I think the labor would definitely be a few dollars. You know how buried those primary injectors are on a full sequential car. That and he has to retain the ACV. He definitely could put the low profile rail in with 1300 cc top feeds and it work great. But then he would have to run an aftermarket fuel pressure regulator ( he could buy an adapter, but it’s suggested to run ID injectors at 43.5 base fuel pressure), new hoses, etc. etc. It starts to become a domino effect. That’s how cars spend years on jackstands. I just think people have a tendency to go overboard on things these days. Sadly from my experience 90% of people should never touch the fuel system for electrical system on their cars.

The bored 1300s have definitely lost popularity compared to new modern injectors. But in this instance, the simplest most cost-effective alternative to either your suggestion or mine would be to add an aftermarket fuel pressure regulator and simply raise the base pressure a few psi as opposed to redoing the total fuel system. I don’t suggest doing that tho for the same reason stated in at the end of my second paragraph. Drop in bored and serviced 1300s have worked great for myself and many others with sequential cars in the 330–350 HP area. Seems like they would be the perfect thing for the OP’s setup.

Side note~ If you decide to go with a aftermarket secondary rail, you should really keep the fuel temperature sensor.

~ GW

suzukisteve

iTrader: (4)

Me and Dale Clark were having this discussion last weekend and I agree with @gdub29e . The top feed injectors are not for everyone.

I am installing the full radium kit (FPR, FPD, pressure sensor the whole 9 yards) and it is not cheap nor easy. You cannot keep the ACV and there is little room for the other solenoids should you need to keep those. Not only do you have to buy all the junk, but you also have to get an hoses and fittings which easily adds $100-200 to the setup. Shoot the adapter to fit the stock temp sensor to the Radium rail is $30 alone. I am on the stock twins, so I really do not need that much fuel anyways. I went with the top feeds, because I wanted modern injectors that would offer good idle control and emissions without the airpump, but that is not an option for OP.

The Rotary Performance rail is super hokey in my opinion. You do not get to keep the ACV with it, but it also does not work well with an aftermarket FPR, which you really need if you are going to run modern top feed injectors. The stock injectors operate somewhere around 38 psi and an ID injector is spec'd for 43.5. Why would you spend your money on fancy ID's just to run them at the wrong pressure and have an invalid spec sheet? I have heard plenty of stories of the 2200cc injectors that come with the rails being difficult to tune the transition for.

The last option is bored out injectors and @DaleClark made a good point about this. The common trend you heard about is injectors getting stuck open or closed. Either situation is not going to cause engine failure. A closed injector is going to cause a flame out. A stuck open injector is going to cause excessively rich conditions, which you would notice instantaneously. I would be warry of sending off a 30 year old injector to get bored out, but you can buy brand new injectors from Mazda still. Get new Mazda secondaries, send them to RC engineering to be bored to 1300cc, run stock pressure with a Walbro 255 and call it a day.

gdub29e

iTrader: (16)

RRR’s viewpoint has a lot of merit. If the op wasn’t full emissions I wound fully agree that a modern injector and new rail are the obvious choice especially with a modern ECU. This instance just seems an unusual setup ( full emissions, haltech, visual inspections, sequential’s, ect) and would be better served by a less complex solution. I will say that buying new 850s and having them bored is not without cost. I agree that is what should be done tho.

I think the radium gear is top notch. If you were re-doing a complete fuel system that was emissions delete they are tough to beat in quality and cost. Pulsating dampener compatible, insulating spacers to stop heat transfer, fuel temp sensor compatible = Sold for me.

~ GW

R-R-Rx7

iTrader: (24)

It seems that something was lost in translation
what i was saying is If you are going to go with the secondaries you might as-well do the primaries also and update everything and not just the secondaries

the level of difficulty to do one rail vs two is the same. And if you are doing the secondary rail only you still have to do lines that connects the oem primary to the aftermarket secondaries
And lets face it, if you are doing the secondaries only its only wise to eliminate the oem fuel pulsation damper that it’s known to leak and start fires. So at the end of the day you still have to remove the primary rail and do it properly

yes its not cheap but adding everything, the bnrs and the haltech elite 2500 and the secondary rail setup etc, adding one more rail and primary injectors it doesn’t really add a huge amount of money to get that up and running

As to whether there’s a secondary rail to allow you to retain the ACV, I dont know any system that would allow you to do that. The FFE light rails appear to have some more room but whether that will allow you retain the acv i dont know. I have yet to install one of those but so far it seems the only potential solution

there are plenty of “bolt on” options from a variety of vendors for a complete system if you feel that the fuel line assembly is too difficult. But as a side note I have yet to see a nice properly optimized” bolt on” setup from any vendor

so yeah the top feeds are not for everyone but the same applies to the performance modifications . They are not for everyone either.

gracer7-rx7

iTrader: (16)

My car has been running the bored out 1300 secondary injectors for 20 years now...
Along with the upgraded fuel pump, powerFC, tuning, it has sufficient for 300-350 rwhp.
Stock primary injectors.

There were some issues of them getting stuck closed/open back in the day so YMMV.

Vasilis Olympios

Thank you everyone for your contributions, very helpful insights.

As a sidenote, FFE claims their secondary 34mm light rail clears all emission components including ACV.

I suppose their light primary rail wouldn't cause any fitment issues either.

I know it's a costly option but both their rails + 1050/1700 IDx (or something similar) seems to be a good option.

Btw since RC notes that when boring the 850cc to 1300cc, they also refurbish it, I am unsure if there's any benefit in sending them brand new 850cc to upgrade however...
I quote from the email I received from them 2 weeks ago:

"RC’s injector rebuilding includes before & after-service flow testing, the injector cleaning & rebuilding, and replacement caps, filters, & o-rings. You’ll receive back a pair of high flow injectors, with all new parts, ready to re-install onto your motor."

I am still undecided on the way to go to be honest, since speaking with a Haltech tuner, he suggested I just up the fuel pressure & duty and not even change anything (I am unsure how good of an approach this is...)

j9fd3s

iTrader: (3)

for 300hp you really don't need injectors, and if you bumped the fuel pressure 350 isn't a problem.

ZE Power MX6

iTrader: (157)

Yup, as I mentioned earlier in this thread, the FFE step up kit is a good option as it works with ACV. It'll be 2nd cheapest option, with the bored injector likely be the cheapest, both are good option tho.

One thing to note on the aftermarket rail, you'll have to bent / trim some vacuum hard line that run up in front of the LIM if you are running seq twins, they'll interfere with the banjo bolt.

Beside that, the step up kit will do what you want and supply all the fuel you need for the twins. I switched to the step up kit with 2200cc injectors + OEM primary 9 years ago and never look back, at the time I purchased the primary rail too and had plan to switch over to it eventually, but never really have the need to.

gdub29e

iTrader: (16)

My only gripe about FFE is you cannot retain the fuel time sensor with that rail. I feel it’s pretty important to keep because you can have a 3% variance without it compensating.

They do make an adapter fitting for the secondary rail you could put an aftermarket fuel pressure regulator on an only have to change one hose. I don’t know what the injector lag would be raising it from stock pressure though. Perhaps you could find that somewhere.

~ GW

gracer7-rx7

iTrader: (16)

^he meant fuel temp sensor not fuel time sensor

gracer7-rx7

iTrader: (16)

No point in getting brand new FI since RC will effectively be rebuilding them to new state... Some people resorted to that back in the day due to an overabundance of caution imo. Some also resorted to doing 1200cc instead of 1300cc fearing it was the increased size that cause stuck injectors. No real evidence to support either being effective...

the larger flowing injectors give you more overhead on duty cycle. you won't know whether or not you truly need the increased fuel until you're on the dyno getting tuned so... it's up to you to decide when/if to do this - or whether to spring for the newer style injectors and fuel rails.

The newer injectors are supposed to be better but only you can decide if that warrants the expenditure... and when you want to spend it. Before you see how existing setup goes or after...

gdub29e

iTrader: (16)

Yes, fuel temp sensor. I’m all thumbs sometimes

~ GW

zli944

iTrader: (2)

Just remember, don't get your injectors cleaned until the end of the project!

had some RC cleaned injectors on a fresh rebuild that would only run on one rotor until a higher RPM. Turned out one of my primaries were frozen since it had been so long after i got them back from cleaning.

RC has a warning on the box and even cleaned them again for me at no cost but definitely caused me some anxiety for a while

ZE Power MX6

iTrader: (157)

The fuel temp thing was definitely in my mind when I went this route, I planned to add the sensor back in somehow if that became an issue, but I never had the need to.

Yup, that’s the key for cleaned injector. My primary was cleaned, and I install it the day it arrived and ran it right away, still ran fine till this day.

gdub29e

iTrader: (16)

Ive seen this happen too. When I received mine back from RC, I had mine sitting around for a couple months. I just took a 9 volt battery and two leads so I could trigger the injector. Sprayed the tip while turning it in and off a few times with some wd-40 and double checked them before I installed. You will hear an audible click. Mine never acted funny. Some of the solutions they use for cleaning, this is a side effect.

Not to derail this thread, are you still using the fuel pump resistor? Which fuel pump are you running? What I found for me personally was when I still retained the two speed function of the pump and was using the smaller GPH unit I didn’t have any issue that I could notice. When I rewired the fuel pump so it would no longer cut back and went with a 450 pump all that recycled fuel started to get pretty warm pretty quick. If I would drive the car more than 40 minutes or so it would start leaning out pretty good. Especially in the summer heat. I actually used an adapter from radium that was made for the stock fuel temp sensor. I adapted it in and after some pretty lengthy testing ( it would only do it after a longer period of time ) I was right around 3% more fuel .


~ GW

ZE Power MX6

iTrader: (157)

I have an Aeromotive 340, also re-wired so constant speed, all fuel mod were done at the same time before the tune. Maybe the 450 is heating up the fuel more than my 340? I have an AFR gauge that I keep a close eyes on, at WOT it has always been hovering ~10.5.

Do you have a link to the Radium fuel temp adaptor? I would be interested to add that back into to my setup.

gdub29e

iTrader: (16)

^
Henry, I’ll shoot you a message so we don’t clog up the thread.


~ GW