Toyotarx7

iTrader: (13)

is there any special wire that needs to be used, as a pre caution? or would regular 10 gauge be ok?

also, im having an issue with this stupid mod, i ran a new power and ground lines to the pump, i grounded the one ground ( obviously ) but where do i stick the power? do i need to buy another relay or is there a spot that i can just tap into?

thanks

BlackRZ

iTrader: (8)

I saw that asianguy02 posted the radioshack partnumber version of the relay, but does anyone know the Bosch part number of the relay I should use? I've heard of this before on the Mustang forums but never really read into it. I'm about to upgrade my FP to the 044, changing my secondary injectors to 1300cc's, perform this rewire trick for constant and consistent voltage, and of course get my HKS F-Con retuned.

helghast7

iTrader: (6)

why 1300's? the 1680's are more reliable

helghast7

iTrader: (6)

were in jersey are you? when the roads are not insane, you can stop by and take a look at my setup, i did this a while back

GoodfellaFD3S

iTrader: (213)

If he's running sequential turbos, the 1300s are a much easier install. Also, although some people have had issues with 1300s, not everyone has--- I ran a set of them for many years with zero issues at 400+ rwhp. Lastly, there is no need for resistors or an injector driver when using a PFC, which is a huge benefit in my book

MOBEONER

iTrader: (18)

I followed this diagram and it works just fine. I like having the cut off switch in the rear bin as well.

BlackRZ

iTrader: (8)

I'm still running sequential turbos, and for the HP numbers I'll be making (hopefully just over 300) 1300's, a 044 pump, and the rewire from this thread everything should work just fine. I've never heard of anyone having problems with 1300's but I'm new and I'll do do some reading for sure now. I bought the injectors from a member of this forum and plan on sending them to RC to get cleaned so hopefully I don't have any issues like goodfellafd3s. Thanks for the questions, it's the only way for me to learn and make the best decisions. I'm not new to performance but to rotary's well, this is a bit different.

helghast7

iTrader: (6)

id rather do it once right the first time, 1300's and injectors that come back from rc have been known to fail, its happened to me with my 850's that have been cleaned from rc took a dump on me, luckily for me it happened out of boost so my 850 primaries were sufficient to run the car in vaccum, but once i entered it was like i hit fuel cut hard

and i personally dont see what the big deal is to do a little wiring to have you preped for when your looking to go for even bigger numbers and lower the duty cycle even more, and technically you save in the long run instead of buying new injectors, deciding you want more power buying new injectors and accessories again, buying rails and what not and being stuck with the slow process of selling used injectors

course im a psycho so i always do things over the top when it comes to reliable power ...mmmmm cant wait to dump my twins and my pfc

what do you think pookiebear richie poo? pectel or motech?

skir2222

Wouldn't this on/off fuel pump switch diagram work just like the one wired to the cigarette lighter since the other side of the power wire that gets cut to go to 87 on the relay supply's 12V to the FP connector? So those of us who have battery boxes in the hatch can wire this switch onto the side of the box so you can turn the power to the pump on and off.

MOBEONER

iTrader: (18)

Why are you going to dump the power FC?
I have been running 550/1300 with no problem with my twins and now I will be running the same Injectors with my 35r.

MOBEONER

iTrader: (18)

You don't have to put in the on off switch, that's just an option.

helghast7

iTrader: (6)

because it is a restrictive old clunker whos capabilities have been far surpassed by current pcm's the only benefit it has is its resemblance to factory configuration and its ease of use for the average person/shop

but being as how i work on my car, i would prefer the benefits of a newer ecu, what pushed me further into wanting this is seeing chris' tone ring for his crank angle sensor

look at the fd's tone ring and ask ray crowe to take a pic of chris' tone ring and you may understand, i wish i took a pic myself

as for the injectors sure they work, and perhaps you have been lucky, but its a risk im not willing to take, i dont trust injectors that have been modified as such as i have had them fail on me before

that plus the benefit of lowering the duty cycle even further has its appeal

skir2222

It was a question if that way would be fine to wire up a on/off switch if you wanted to...

BlackRZ

iTrader: (8)

Mobeoner, is that a common problem with the 1300's or maybe one that just accidentally happened to you? Also I understand what your saying about the bigger injectors and lower duty cycle. I must say I am some what stuck in my Single set of injector ways, meaning that bigger isn't always better, since the computer has only one set of injectors to work thru and too big of injectors end up causing a rough idle. But the great thing about rotaries is that you have the two sets of injectors to play with and I guess that makes things a lot easier. I don't want to high jack this thread so, thanks for the input!

Josh

helghast7

iTrader: (6)

your secondaries dont interfere with your idle, your primaries are your main injectors during vaccum/low rpms, im currently running 850's as my primaries and have no idle issues, as for 1680s in the secondaries, ive heard only few complaints about a slightly rough transition from primaries to secondaries, but with fine tuning those little flaws vanish

generally speaking bigger is usually better, of course there are exceptions, the lower the duty cycle the more reliable the injectors become and the safer the tune gets, too high and you have a chance of having an injector burn out or get stuck either open or closed..neither of which is good

ok im going to try to answer this as unbias as possible....1300's are good injectors for what they are..which if you didnt know.. they are simply our stock 850 secondary injectors bored out to 1300 cc's of flow, the reason why they are good is the same reason there is a potential for them to fail, someone took them apart and modified them

as for failure rate, i must say it is not extremely high, but it does happen i couldnt give you a percentage off hand
(heres the bias part) but seeing as there is the potential for failure is reason enough for me to not use them, especially since ive never heard of 1680's failing

its all preference, yes 1300's are an optimum size for twin turbo setups and small single setups since they have a large flow and wont give you the transition issues that the 1680's might, hell technically the max cc's the pfc reaches is 1300 cc's

but the 1680's give you more reliablity and lower duty cycle

and lord knows we need all the reliability we can get

MOBEONER

iTrader: (18)

^^^ correct. The 1300 are good for twins or small single turbo for low 400s, rich was in the low 400HP range with the 1300s and so is chrispyrx7. I am shooting for 400HP so i will keep my 1300s. If the 1300s become a problem i will jump over to the Injector Dynamics (no resistors) and leave my pockets like Rabbit Ears.

BlackRZ

iTrader: (8)

Thanks, for the input. Already have the 1300's on the way, had I read something about the failure rate before I probably would have went with the 1680's. I've been trying desperately to see if I can import my car under a show or race clause since my car isn't on the approved list to be imported. But they want your car to be extremely rare for the show car clause and it has to look like a nascar to fit in the race catergory not to mention they want to know what events, races, or shows the car will be entered into. So now I'm just trying to have fun with out breaking the bank before I come back to the US in a few years and purchase a FD there.

twinsinside

iTrader: (34)

lol small world. You own the black one on base right? Think I was parked next to you tonight at the SS 7-day store around 1800.

Only issue with going with larger than 1300's is removing all the air pump associated stuff and getting a fuel rail. ID2000's and a secondary rail are the way to go if you don't want the air pump in there. The injector dynamics ones don't require resistors or an FJO driver which is a real benefit.

by the way, importing the car will be a no-go. I've known a lot of guys here that have tried, one guy even cut his in half before finding out that wouldn't work either.

BlackRZ

iTrader: (8)

Funny, yes that was me last night. Yea I've been calling back to the states to DOT and the EPA asking questions, this is my third time in Japan and third time trying to work it out. At this point I plan on selling the RX7 before I leave and buying a AE86 since the 25 year rule will be in effect for that car and bringing that back instead.

Trout2

iTrader: (5)

More people have used 1300's with no problem than those that did have problems. Wat overblown myth. In my opinion the 1300's got scape goated by some builder's that didn't want to admit it could have been something on their end.

I used 1300's for over 6 or 7 years about 39,000 miles before switching to 725/2000 Injector Dynamics. I personally have witnessed several other local FD owner's use the 1200/1300's with no problems long term. Those 1680's are what's obsolete now.

Jack

helghast7

iTrader: (6)

Your running the id's with the PFC?

Trout2

iTrader: (5)

^ yes, Power FC. Works great, much better idle with the ID725's than Denso 850 primaries.

Jack

helghast7

iTrader: (6)

whats your duty cycle?

thats an interesting setup,to be honest im only running the 850's because it was cheap and i didnt want to change anything till i upgraded the rest of my fuel setup to mirror my turbo and pcm setup, my 850's all around is sufficient enough to run the twins

Trout2

iTrader: (5)

Not sure which duty cycle you're asking. Idle is about 4.1-4.3% with mid 13AFR's and max is 70% at 16psi (street port with Aspec 500R).

With (4) 850's at 11 psi (street port with sequential twins) I saw low to mid 80%'s duty cycles in Summer so I upgraded to 1300 secondaries before winter and it droped to low 70%'s at 13 psi.

RotaryEvolution

iTrader: (30)

if it hasn't been mentioned in this thread i will say it now before everyone thinks they are safe with the fuel pump rewiring.

get rid of the plastic 4 pin connector passthrough for the fuel pump while you are doing this modification, the higher voltage and strain on the wiring from larger pumps will cause that connector to fail and possibly lead to engine damage.

find some isolator bulkhead connectors and bypass that stock connector completely for the fuel pump wiring.

i have seen them fail numerous times, not only on FD/FCs but also on domestics with walbro pumps. when increasing the pump's volume it requires more electrical juice which puts too much strain on the already marginal stock wiring and connectors.

there is a thread somewhere here in the third gen section for part #'s and how to's on doing the bulkhead connector modification.

edit: here you go:

https://www.rx7club.com/showthread.p...head+connector