To the guys running bored out 2nd-ary's:
what type of ecu are you using with it? I assume you don't need a new fuel rail because they are just bored out and will fit back in...?
What was the turn around time on the boring of the injectors?

I have a upgraded fuel pump but no new ECU yet...
Can you run 1300 secondarys on the stock ecu?

How does 1300 secondarys affect gas milage (I know it doesn't matter, but I am curious).
besides fuel pump and ECU are there other things that need to be upgraded to accomodate for bigger secondarys?

Thanks!
-Dave

 

No you can't run larger secondaries with the stock or modified ecus (Pettit, M2).

Looking at your mods, you are a LONG way from needing fuel upgrades.

you won't need to upgrade fuel until you are pushing 14 psi on the twins, switching to upgraded twins, or getting a single turbo

mod progression:

downpipe
cat-back
intake
ecu
intercooler
hi-flow cat or midpipe

then larger secondaries and upgraded fuel pump IF your injector duty cycles require it. With the above mods, you should still be able to run 12 psi with the stock fuel system.

 

Well, I have the intake, intercooler, downpipe, and fuel pump and I am looking at ECU's and exhausts. I am just trying to figure out the order of the ecu, exhaust and injectors...sounds like injectors are last. ECU first? then exhaust...then injectors?

 

If you keep your boost level at 10psi then you can get an exhaust first and then the ECU.

 

yes you can run larger secondaries on stock ecu. you'll just run rich.

 

Ok, yes you can run larger secondaries on the stock ecu but you cannot adjust for the larger fuel quantities and you will run PIG rich, especially considering how rich the stock ecu runs anyway.

I know you technically can, but would you recommend it? I wouldn't it.

 

I agree with Rynberg, you'll run ridiculously rich. The stock based ECU will still think that it's controlling 850cc.

 

I see so many types of injector and fuel pump combinations with different FPR's, rising rate, boost dependant, etc. People adding additional injectors, running three fuel pumps, internal, external......... . Then you get into fuel pressures and flow rates...it's very confusing to me. I would like to know which set-up is the best for certain hp ratings. For instance a set-up for 350, 400, 450, 500, 550hp. Which set-up would be the best for each situation and why?

 

I agree with Crazy Jake, it's crazy. The CWest in the SCC us using three fuel pupmps. The article states the FD tends to lean out on turns. Personaly, i'd rather do a drop in 1300cc than changing or adding a fuel rail.

Click "here" -> for table that shows fuel injector fuel rate

 

I totally agree! I don't want to have to change the fuel rail if possible. It seems these cars don't like to be tinkered with...

 

yeah that's exactly what i was saying it can be done but you'll be really rich. now, has anyone tried to use bored secondaries and a simple fuel controller like the apex s-afc to lean out the a/f ratio? how did it work out? it would seem that the ecu would reduce flow through both the primaries and secondaries, which would cause some tuning problems when you only want to lean out the secondaries. are there any simple fuel controllers out there that can directly drive the secondary injectors separately? or do you need a full standalone?

 

Check my sig to see the power I'm putting down. Been doing running this setop for ~7 months. RC Eng will bore out your 850ccs to 1300s, turnaround is a week or two. They'll fit right in your rail. FPR isn't necessary. I'm running the rx7.com fuel pump, which I'm almost positive is a supra tt fuel pump. That and a power fc is good for over 400 to the ground after I upgrade my stock twins. Not really that complicated

 

If you look at most of the sigs of the heavily modded FDs that aren't running singles (and even some that are running singles) - they are running the stock 550cc for primaries and RC Eng. 1300cc secondaries. Why? Because it's proven that it will work. This setup is good for almost 400 rwhp running at 80-85% on their injectors. This is probably the most popular and most used by most modded FDs. 1200cc secondaries are fine for somewhat heavy modded FDs running 340-350 rwhp. I wouldn't upgrade to the 1600cc secs unless you know you'll be pushing 420-450 rwhp consistently.

 

so, short of stand-alone, is there anything than can control just the secondaries so that i can lean them out independent of the primaries?

 

Not that I'm aware of. I'd start saving for a Power FC

 

rich,i gotta love that new avatar....sadly...i'm actually getting used to seeing it here in college life..hehe.

the power FC is one of the few that will control larger secondaries....

RICH--did you ask your friends if it could be done with the EFI unit? Dave from KDR said it could...so i'm thinking about upgrading my secondaries when i go higher boost.

Danny