silverflash2

iTrader: (2)

I'm still on the stock turbos, but plan on going single down the road. I blew my engine from running 16lbs on the stocks turbos. Ran great for 3 months, then one day i lost a coner seal. So i'm pretty sure it's from a fuel pump or pushing the injectors at high duty cycle. So i bougt a TT supra pump, and all the stuff for 850/1600 injectors, and PFC. And plan on installing during the rebuild. I searched and didn't find anything on this fuel setup with stock turbos. Am i gonna have a hard time getting it tuned and running smooth,with the over kill of fuel setup. Or should i put this setup aside and wait till i get a single turbo and run the stock turbos with the old injectors on lower boost.

IRPerformance

iTrader: (41)

You can, just note that you will need to delete the ACV is you haven't already done so to clear the new fuel rail.

gracer7-rx7

iTrader: (16)

Hmmm.... Didn't know the stock injectors handle 16 PSI of boost. I always thought they couldn't. I know the stock ECU doesn't support air flow too much over 10-12 PSI.

For stock turbos, yes the 1600's are overkill but can be used. Bore out the 850s to 1200 or 1300cc and that will work very well also with much easier installation and much much lower cost. I'd personally wait until you go single turbo before dumping all that cash into the fuel system.

I'm running stock 550 primaries with 1300 secondaries and a fuel pump and that is enough for 350rwhp on a ported motor with twins.

rynberg

Way overkill but it can be tuned for. It's still a lot of work to reinstall sequential twins with that fuel system and then later switch to single turbo.

NoMorePoison

iTrader: (1)

So is 550cc and 1300cc with a walboro not sufficient for say, a gt35r kit?

Oh and also an fpr

pwwatkins

there is a fuel calc. at rx7.com If I were you I would get someone's used 850's and put time in the primaries, then when you go single get some 1600s for the sec's. Unless you are going single real soon then just wait to do your fuel until you go single.

NoMorePoison

iTrader: (1)

So even the way as it sits I should upgrade the primaries? I just dynoed at 318 on my stock twins at about 14 lbs and my AFRs never went above an 11.9 or so. A couple of guys I know here in town said that going to 850s wouldnt really open up much for me right now

rynberg

On pump gas (limiting you to 15 psi or so), that should be enough. You don't need an aftermarket FPR for that setup.

No. And you are running too lean at 14 psi. You should be more in the low 11s:1 (doesn't Idaho only have 91 octane as premium?).

NoMorePoison

iTrader: (1)

93 but its ten percent ethanol. thats seriously to lean?! I guess its back to the tuning bored haha

silverflash2

iTrader: (2)

What do you mean by alot of work, In that i have to get it tuned for twins, then for a single? Or is there fitment issues? I have a brand new PFC that needs be tuned when i install it anyways. The turbo i want is 3500 + that why i have to wait. I'm getting the motor ported, so i figured i'll need more fuel anyways, and bought Dhahlens used fuel system. I'm tight on money now with this rebuild,I have this fuel system i can use. From what your saying i should put it aside, and run the stock stuff until i get my single.

rynberg

I'm just saying that because you'll have to work with the rats nest during this install and then have to go back in there for the single turbo. But there's nothing wrong with installing it now. I remember you blew your motor last year because you didn't listen to our advice, so I hope everything works out this time.

silverflash2

iTrader: (2)

Thanks, Rynberg, Yeah I remember you telling me. I know you have alot of experience and i appreciate the advise, and I have learned my lesson the expensive way.

gracer7-rx7

iTrader: (16)

Fitment issues as rynberg alluded to. Ccarlisi did that install on stock twins for a while iirc. Try searching here or on nopistons.

I personally would put it aside for now. You don't have a definitive need for the amount of fuel 1600s will give you and the stock 550s with 1300s will work well and drop right in. Do have both sets of injectors cleaned before you reassemble the motor. Cheap insurance.

G's 3rd Gen

iTrader: (11)

So were you running that boost level w/ stock injectors or would spike to that and level off lower? I'm suprised it lasted 3 months. I make sure to add a few gallons of 100 tw/ my 93 for the extra 1 to 2 psi spike. I have been fine for 4 years and 13000 miles w/ my set -up 550 and 1600's. What were the symptoms? Hard to start , restart? Or gradual decline in performance? G

silverflash2

iTrader: (2)

I had a HKS PFC FCON (piggy back fuel computer)and FCD and greddy profec B-S and had my high setting to 16 lbs. And it was a blast to drive at 16lbs. It would hit 16 lbs with just a touch of the throttle. Never had spikes.Stock injectors and fuel pump.Did fine for 3 months as a daily driver, then I did a u turn and got on it, and a large cloud of smoke came out,then a bad idle, and lost of power.Could be bad gas, injectors maxed out or stuck,or stock fuel pump wasn't efficient. Car is slugish from a stop, but higher rpms it still rides out with the 16lbs of boost. I'm basically running on one rotor.I can still drive it but, It's embarassing to drive my car with the stinky exhaust and bad idle and lost of power. So it sat for 7 months, and it won't turn over anymore.

RX7 RAGE

iTrader: (22)

550/1300 would be good for stock twins. i'll be using that combo on my bnr 3 twins.

IRPerformance

iTrader: (41)

I'm not a big fan of enlarging injectors. If I were to do it, I would do it with a brand new injector. I've done plenty of cars keeping stock twins, sequential turbos, and 1600cc injectors. The tuning really isn't an issue. The problem is if you need to pass emisisons and need the air control valve.

rynberg

I also agree with Ihor.....I would not be running 1300cc secondaries if I didn't have to pass emissions. Of course, I wouldn't be running BNRs if I didn't have to pass emissions either....

G's 3rd Gen

iTrader: (11)

Sounds like the injectors were maxed and when you u-turned it also created fuel slosh which starved the fuel system and a lean condition. Sucks nevertheless. G

GregFD3S

I have a GT35R surpassing 430 RWHP and I have 550/1300's. Im cutting it close, like 85% duty, so I would guess you can do at least 380 RWHP.