Rx7UpYurs

my FD is currently in the shop getting a T04E installed on a stock motor along with PFC, upgraded fuel pump and aftermarket FPR...im just wondering if i need to upgrade my injectors also? i've tried the search function but it doesnt really give me a direct answer...thanks

toddp31

How much boost do you want to run? You might as well upgrade to sec 1300/1600, better safe than sorry. I sure someone with a t04 will chime in.

Rx7UpYurs

i plan to run only 12psi, maybe 14psi max

Badog

What ECU you going to run?

You're going to need more fuel starting at about 340RWHP (injectors are at max point) unless you up the fuel pressure from stock levels. You're not going to do that unless you have an upgraded FPR.

I would think you need to upgrade fuel if you don't want to max out the stock setup and WANT to make more than 350RWHP.

Next question you should ask is 1600's with a new 2ndary rail or upgraded 1300's?

Goto Max Cooper's site and check out the fuel calculator. I'd keep the primaries stock, or go with upgraded rail and top feeds rather than 850's in there.

Tony

Rx7UpYurs

my fuel upgrades are; cosmo fuel pump, paxton fuel reg and Apex power FC...is that enough for me to run the car without blowing it?...i want to find out while the car is still in the shop, so if i do need to upgrade the inj. it would be easily installed....btw, thanks for all the replies

Badog

If running the injectors at duty cycle 100% is bad
and the stock injectors support ~340RWHP at 100%,
and the maximum recommended duty cycle is 80%,
will you be happy with 271RWHP? (80/100*340)

Let me summarize the messages on this thread: UPGRADE THE INJECTORS!

While you're at and if you're really smart, send the ones you don't upgrade out to be cleaned and flowed by RC Engineering.

apexkw

i would get new injectors. probably 1300cc. better safe than sorry at this point in the game

Rx7UpYurs

ok i will upgrade the injectors, heres another stupid question...do i just pull out the orig injectors and have them cleaned/bored out?...or do i just buy brand new ones?...if i have to buy new ones, where can i get them?...thanks

toddp31

It depends on what you want. You can send away your 850's and get them bored to 1300(will fit in stock rail). Or buy new 1300's or 1600's, but with them you will need a new fuel rail and hardware. KDR and Rx7.com have what you need if you go the new injector path. There are tons of treads about this subject( 1300 vs 1600) up to you to decide. I went KDR rail with 1600's

Northwest FD3S

Here is some other infpo while upgrading injectors. If you do go with 1300/1600cc injectors, they will be top feed. This means you need to upgrade the fuel rail as well for top feed. Now that you have this new secondary fuel rail you run into the next problem. The stock primary fuel rail and the oil injectors get in the way of the new top feed secondary rail. So now you need the upgraded primary and secondary fuel rail and 1300/1600cc secondary injectors and then you can get a pair of 550cc top feed injectors out of a TII. This will clean up all of your fuel needs and look very clean under the hat.

maxcooper

There is no such thing as new 1300 cc/min injectors. They are all modified 850s, so you might as well have them do yours.

-Max

jspecracer7

My secondary top feed fuel rail did NOT get in the way of my stock side feed fuel rail. I'm still running stock 550cc side feed and 1680cc top feed injectors.

The problem you will have however is with the top feed 1680cc injectors, you will need to remove the ACV and block it off so that your secondary injector rail will clear(since it is too tall).

Badog

jspecracer7 is all over this one. ACT block off plate, no problems with the stock primary, but why not take the oppourtunity to take the fuel rails to parallel instead of serial feed? Check out Keith's rails at http://www.3rdgenrx7.com/keithsrails.htm

rxrotary2_7

here is a picture of the rails anodized in blue.

Rx7UpYurs

thanks for all the help guys im sending my injectors to RC this week...im going with the 1300cc/1600cc set up, as apex said "better safe than sorry"

insomniac

iTrader: (5)

Off topic: Who's going to tune your PFC for you? XS I suppose?

Rx7UpYurs

yeah...since we're on that topic, heres another question; can i dyno tune my car right after i get it or do i have to wait until the "break-in" period ends?...if i havent mentioned it, i have a mazda reman getting installed along with the T04

Badog

If it were me, I would break-in the engine for 1000 miles with no boost for the first 500, then build up to 5 psi the last 200 miles. Change the oil at 500. Mix up the driving....not just steady state freeway miles.

matty

80% is low for me...anything after 300rwhp and u need to upgrade.