will 1000cc injectors
 

i have my rtec 2.1
but all i have are 2 1000cc injectors for secondarys
can i use the 550s for primarys
with a bnr turbo stage 2

will it stumble and act up
or can it be done with no problem

i have a 87 t2
walboro fuel pump
fmic

Having injectors that are very far apart in flow ratings are not recommended.

what do you recomend

720cc secondaries.

4x 720cc injectors will be just enough at reasonable duty cycles.

has anyone got any decent hp with this set up

get some 750cc for the primary and you'll be set. There are Rtek7 2.1 setups claiming low 12 sec ~115 mph trap speeds with similar fuel capacity = very respectful HP. My Rtek7 1.8 cycles the 720's @ ~ 5-6% duty cycle @ 900 RPM which equates to over 3 ms pulse width so there's plenty of room for idle adjustments with the 750's.

i put in 720 1000 setup in mine but it wont run on the 720/720 setting. it only runs and idles on the 550 550

You're doing it wrong....

maybe the start map got wiped flat when you changed it over... i would at least run the 550/720 setting..

Does any one know if i will have issues with 550 pimaries and 750 on secondaries?

What fuel pump and FPR? If walbro 255 and a stock FPR, you'll end up with excessive fuel pressure at idle/low throttle.

Not if you're using the 550/720 setting. The difference between 2600cc (2x 550 + 2x 750) and 2540cc (2x 550 + 2x 720) is only 2% additional fuel when the secondaries are active.

i have also a 255 lph and stock fpr
what should i do to make this work

i see some use 720 asome use 750...where can i get the 750s if there better

Not that they are better. Check the price on these low impedence type and compare to the 720's (nippon denso?). I think you'll find new 720's to be quite a bit more:

http://cgi.ebay.com/ebaymotors/2-Sie...Q5fCarQ5fParts

720/1000 cc injectors worked well for me. 720/720 setting

do you have your settings to share with us

im running 850 /1000 with a walbro 255lph on the 720/720 settings. The fuel map fields in the cruising areas are all over the place but it works well with this setup.

Well after some consideration I changed my settings to 550/720. Pulled about 28 - 31 from 2psi to all vaccum. Then used solareons fuel map in boost areas and still had to pull that alot. So far I'm up to 13 psi with a 68.74 duty cycle. Afrs seem to run around mid 11's sometimes hits 10.9. It feels good but I want to hit the 320hp mark. I'm hoping this can be reached at 17psi :)

You do know the MAP sensor is limited to <15 psi. If your engine is ported and100% sound, 320 whp is reached @ <15 psi via RPMs.

I've used 720/1000 and even 720/1600 with rtek 2.1 without any issues.

Be careful when exceeding 15psi on the stock map sensor...

Yep. I'm using water injection to try and help prevent any issues up there. I have enough fuel for it. My setup is....

S4 N/A keg with fd oil pressure regulator (otherwise stock)
S4 hybrid, to4b v trim wheel, 38mm wastegate
Fmic, mounted in the spot of the radiator
2.5 dp and mid to 3 cat back
Walbro 255
820cc / 1000cc
400cc water injection pre turbo
Apexi AVCR boost controller

In reading that preturbo injection will move the compressor map up and the right, I hope to still be in the efficiency range at the psi. My goal is 320rwhp. True I may be at that now but I don't have anything to compare it too :(. If I don't reach that amount by 17psi I'm not going higher but I really would like to see what it's like.

so i just got my rtek 2.1
my current setup.....s4 turbo motor with minor streetport
bnr stage4 turbo with full racing beat exhaust
fmic with tial b.o.v
all emmisions removed
act 6 puck with 17lb flywheel
rc 550cc/1000cc
walbro 255lph
..........
with this being said what shold be a good primary setup to use to go to the dyno to fine tune?
550/720 preset? any help or maps would greatly be appreciated!

550/720

you'd be better off with 720 primaries considering the air a stage 4 bnr can move and the rather large transition from 550 --> 1000. How much boost do you plan to run?

I have no issues running 550/1000cc on the 550/720 setting

planning on running as much as possible and be safe, so im assuming max will be 15psi b/c of the factory sensors. is there anyway around that to push more that 15psi and be safe?