Whell i will be going BNR Stage 3 in the future and was wondering what size secondarys would be good for running about 15-16 psi

 

27 views and not one answer

 

1000cc

 

I went with 1300's for secondaries. Motors not broken in yet, so I still need a tune. Cant wait to see what the BNR's will do!

 

850s in the primaries, or 1300s in the secondaries... or both...

 

ok so pretty much 1300s.. it would still run fine with the stock twins for now tho right? and what was the place that people send them in to get bord out?

 

You'll have to tune your map to run the 1300s, I don't believe you can just slap them in. Most people get them bored at RCengineering... I've heard bad things about this process, but I can't remember what it was I heard...

 

You can run the 1300s with the stock twins. They are a direct replacement of the 850s. rx7store sells the 1300s for like $330 for the set with exchange of your 850s. Or you could buy someone else's fairly used 850s and send them off to be bored out to 1300s and still have your original 850s in hand for a rainy day. (Someone just suggested the latter to me).

 

I went 4x850s. got a cleaned set from a reputable forum member for cheap and i sent my stock ones to kgparts along with my primary to be milled so they will fit. much cheaper then the 1300s and i trust it more. just a few adjustments on the pfc and my rebuild started fine first try and runs smooth as butta.

 

i was running 910cc primaries and 1600 secondries with my to4z

now am running 1600cc primary and 4x 910cc secondries with my t51r

just make sure you keep your injector duty low its always better

 

already have extra 850s on hand... how much is it to get flow tested and bord out from the rc place?

 

bump

 

I just got a set of 850s customized from RC Engineering. Think it was 175 per injector and the turn around time was about 2 days (not including shipping). 550/1300 is a pretty popular combo.

 

btw, when I said "I don't believe you can just slap them in", I meant because of the tuning, not the size of the injector itself.

PM mono4lamar for a good set of 850s

 

i would go with the 1600 right away since so many people have had problem with the 1300, just spend the extra bucks and be done with it for the future.

If you install 1600, you will need an aftermarket fuel pressure regulator so you will be able to eliminate the pulsation damper instead of paying 120$ to install a new one if this is not done yet.

 

I'm inclined to agree with Puma about the 1300s. I ran them (along w/850s) for years with zero problems, but many others have had problems with bored-out injectors. And these are serious problems, as in blown motors

If you want to push the BNRs like I did (17-18 psi) you'll definitely need 850/1300 or 500/1680. I'd say go with the top feed 1680s, keeping in mind you'll have to delete the air control valve in order to install the rail.

 

ok could i run lets say the 1600s with the stock twins for now? with no modifications to the fuel rail or anything? i mean they are my future plans to get BNR but atm i got stock twins and pushing 90% inj duty which i want to lower a bit..... so i figured to get the injec now

 

Nope, the 1680s are top feed injectors and need a top feed rail. The stockers are side feeds. Probably your best bet right now is to run four 850s. But, you're probably ok at 90% IDC---the side feed injs are cooled by the fuel flow, so you can max them out much more safely vs the top feeds.

 

max i hit was 97% inj duty and i dont want to see 90s anymore.... so what would be the best and least moding to do

 

stock primaries and 1300cc secondaries should be fine for 15psi on a stock port motor. I run 4x850cc at 15psi on a stock motor and hit 87% inj. duty, and 550cc+1300cc is more available fuel than 4x850cc.

Also it seems like the side feed injectors take higher inj. duty's better than the top feed. I've personally never read of anyone's stock inj. giving them problems from high inj. duty. Not saying it hasn't happened, I've just never seen anyone say it.

 

If you dont plan to road race or beat on the car for an extended period of time, you might be ok with stock injs. How much rwhp are you making right now? My dad has been running 290ish rwhp on his FD for 4 years/43k miles now with a completely stock fuel system.

 

i have around 270 when i got tuned.. also with a slipping clutch..

 

I plan on trying to get my car to run off of E85

Since the octain rating is much high (Harder to burn/ less power)

do you think it would be a better Idea to run 850 primary, 1600 secondary, APEXi Skyline fuel pump, CJ motorsports system, with a aftermarket FPR (suggestions)

I was thinking this would be best, because I rather have too much than too little...

I can run at a lower IDC if needed, but I don't know if I'll need more umph with running E85

suggestions?

 

Bump!

I have talked to a reliable source and he stated that unless you car is pulling some crazy amperage, then your fuel pump actually recieves 13.5 volts (at least) durring driving.

He also stated that with upgraded fuel lines (Larger volume) and a high volume pump in the tank along with a high pressure pump up front that you'd be just fine.

Any thoughts on this

Basically I was told that the APEXI pump is way overkill...

let me know what you think.

 

Bump

Anybody have any thoughts on my posts?