ravencr

What is the stock injector size (flow rate) in cc's with the 3.4 Liter V6?

Also, has anyone installed a 7th injector instead of replacing every fuel injector to save money? I'm very interested in finding out more about this method of increasing the fuel flow. I got to thinking about this and the capabilities of the SMT-6 and FTC1-E today while talking with Mark at Split Second. I'm wondering if having the piggybacks control the 7th injector could easily allow for us to run a very big 7th injector and keep everything else stock. It would be cheaper, possibly, but I haven't seen anyone do it yet. Here's what I'm talking about:

1) 6 x 305cc = 1830cc total flow
2) 6 x 370cc = 2220cc total flow
3) 6 x stock = ?????

Then take what the difference between the stock total flow, and buy one huge size injector to make up the difference to the total flow for 370cc's. This way I was thinking we could prevent the flow of the 7th injector until our engines are started, and then at any rpm or boost level we wanted, but I'm not sure how it all would work yet. Mark, at Split Second, said they could make the FTC1-E control the 7th injector pretty easily in addition to what it already does, which would be sweet! So, I'm thinking if this is the case, this could prevent any possible hard starting problems since the 7th injector's fuel flow wouldn't occur until the engine is already running. What does everyone think?

Chris

CTB

Where are you going to be putting this 7th injector? Just wondering.

Dr. Zhivago

Chris,

bbeast had a 7th injector installed by IDA when they installed his SMT-6i...

He said he was going to update that info soon.

Dr. Z

PS I think the injector size on your truck is 245cc.

ravencr

It's very important that I find out what the exact stock injector size is. Thanks Dr. Z. It looks like I may have to talk with Toyota to find out the exact flow rates, unless someone on here knows for sure what the flow rates are for a 1998 4Runner with the 3.4 Liter V6??

Chris

Gadget

The stock injector is the same from 96-98. I flow tested one at 238cc.

Gadget

www.GadgetOnline.com

ravencr

Hey thanks Gadget! I can always count on you for the exact information I need. Thanks a lot, and just wondering what you thought about my idea about running the 7th injector.

Thanks,

Chris

Gadget

I think that out of all the Band Aid fixes, that is the best one.

I can curious to know where your are going to have the "7th" injector installed. You are not really planning on installing it before the supercharger are you????

Gadget

www.GadgetOnline.com

ravencr

When you say band-aid fixes, how do you feel it's any different than buying all new 370cc injectors from RC Engineering? I figure I would need a 810 injector as the 7th injector to equal what 6 370cc injectors could flow at. I don't know. DuffDog just replied saying that it would be better to run all new ones, because you won't know if all the cylinders will be receiving the same amount of fuel and chances are they will not. Maybe it's not a good idea, but I'm not totally convinced either way at this point. I'd honestly like to get all 6 370cc injectors, but it's a money issue right now. I can't stand waiting on getting the supercharger installed. It's frustrating knowing it's sitting in my garage just waiting to be installed. I don't know, but I'm trying to cover all possible bases. Here's a recent message Duffdog sent mewith regards to his setup:

"well you theoretically could install a 7th injector in the throttle body-- just like old time chevy engines, but i would rather skip the additional injector control and just get 6 correct sized ones. custom machining an injector orifice and hoping that it works correctly-- ( keep in mind, if you use a 7th injector, there is no guarantee that all of the 6 cylinders will get equal amounts of fuel. There was a huge problem with ford 5.0liter engines because the air intake runners did not give the same amount of air to all cylinders, so some cylinders were rich and others were lean and there was no way to fix it with the type of injector control ford was using at the time. if this is the case with the supercharger, the engine may perform as if it had 4 370cc's , 1 300cc, and 1 200cc injector and the cylinder that just happened to have less fuel would fry first. ) I dont think that 450dollars is too much for 6 injectors from RC, and you wont have any problems either. by the way, stock is 270cc in 1998. The isr mod wouldnt apply to me since i have a different intake altogether. The perfect power sounds like a good idea-- but i havent seen any race cars with it so i dont know how well it works.

I really think that the fuel injectors are the deciding factor in
the power im producing--and maybe the install. Plus the RC 370cc
injectors fit right into the orifice with no problems, all you have
to do is cut off the plug and wire in the new plug that they
supply. ( and use 2 o-rings to get a good seal) I picked the apexi
safc because it works really well and is a digital device instead
of the split second stuff which is analog and cannot address
specific RPM changes. In addition to that, if you are near an
import tuner store, they can program the SAFC to get every last bit of power from your engine. to get the intake, i walked through a pick-n-pull and found a 85 4.3L blazer intake and took it off, it was even the correct angle for my supra MAF mounted on the stock airbox. Pulleys might not be a good idea because there is such a thing as overspinning the roots charger and that will toast your engine and give you minimal power. The fuel pump you have should be fine-- I would definitely want a 255lph pump because bigger doesnt hurt anything with larger injectors. The spark plug thing doesnt really do anything, its sort of like a band-aid for too small injectors. I dont know what the ISR mod is ( please enlighten me ) -- since you have a 1998 runner, you should be all clear and have lotsa power if you do the same mods. the older trucks had all the stupid problems. ( pre 1997 )

1) i picked the 370cc injectors because i called the folks at RC
engineering and said I wanted the best injectors for my truck which would make the most power. The tech said these injectors were used in racing tacomas and worked very well. He also said that the pattern spray on these injectors is superior to any other ones and would give me better atomization. Is this in comparison to the Supra N/A 305cc injectors that everyone except you are running? If that's the case, I'm definitely buying the 370cc injectors, because I want to push the HP you're pushing. If all this is the case, then what is the best method for me to make sure the RC injectors will fit, and what will I need to buy in addition to the injectors to make them fit into the wiring harness? Do I need to send RC Engineering one of my injectors so they can duplicate it easier?

2)I run the SAFC Any reason why you picked this over the Split Second FTC1-E? Apexi makes your unit, right?

3) I dont experience hard starting and i dont know why, maybe my injectors have something to do with it. like i said, only
certain NA supra injectors work--others dont, i cant understand why people dont trust me on this, i have a box of the incorrect supra injectors and they do not fit well. Well, it looks like I'm
going to be the second person to test out your same setup. I'm nervous about it, but trusting and hoping that my 1998 4Runner will run the same as yours.

4)yep running the supra maf with a 4" intake from a chevy
4.3liter v6--fits really well. What parts are you using from the Chevy? I just bought the stock intake parts for the 1996-1998 & 1999-2001 so I could make the Deckplate and ISR mods since I had a FIPK now.

5)my pulley is the stock one, i had pulleyboys.com mill me a
custom 15 psi pulley, but it made my truck backfire, so i took it off.
I was thinking about running a 9psi pulley. Have you tried that?

6)i chose them because im stupid and thought that i had a fuel pump problem with the 255lph pump, but it was really my SAFC set incorrectly. I took the fuel sender to a machine shop and they custom welded piping to use 2 supra pumps simultaneously and now im stuck like that because they had to cut off the inlet line. But they work good and the pumps are only like 70 bucks each. Right now I have the Walbro 190 LPH. Do you think it will be enough with the larger 370cc injectors vs. the 305cc's? I was thinking about running the 255LPH, but I wasn't sure which one and even if it would be needed. What do you think?

7) NO no no no-- you dont need colder spark plugs for any
reason! i run stock nippon denso plugs and dont have the slightest bit of pinging. That's really weird, because a ton of folks are running the 1-2 step colder plugs.

8) deckplate--well actually i cut a 6"x7" hole in the front of
the airbox to let the max amount of air into it. headers, custom
exhaust with 2.5" pipe and a plain ol flowmaster., and i have the TRD posi in the rear and a manual transmission. Sweet! I've completed the deckplate mod using a 6" unit, which came out really well. I'm going to be doing the ISR mod, and then I'm wrapping it all with thermo-tec air intake wrap and thermo-flex to keep it as cool as possible.

9) just do the same crap i did. but make sure your truck is
newer than 98-- if its older, than you will most likely get the same
crap everyone else is experiencing--hard starting, drop off, smoking, pinging, backfiring. It was only in 1998 that Toyota re did the program in the 3.4L to accomodate the supercharger-- before that, TRD was a separate entity.

Gadget

Yep, BANDAID FIX.

No matter what you all think TRD did to the ECU program in 98 it still uses the VERY SAME fuel injectors that my 96 and 97 came stock with. You can program your ass off, but you are still not going to get an injector that is to small to flow more fuel then it is physically capable of. In the end it will still run LEAN, because the injectors are TO SMALL.

If you are running the stock timing you ARE NOT GOING TO GET MORE POWER FROM 370cc INJECTORS then you will with 305cc injectors. If you are tuning for best power with stock timing, you will LOOSE power if you run it richer.

If you run it richer then you can with 305cc injectors then you are really going to have to ADVANCE the hell out of the timing to make more power.

The 305cc injectors have been proven time and time again to work FLAWLESSLY with either the stock MAF or the Supra MAF.

We know that there have been serious issues with the 330cc injectors or what ever they really are, that MAW has been dumping on the market. Know one really knows why they don't seem to work well. If you want to venture out there and try some new ground breaking combination I wish you all the luck in the world.

I can tell you this for sure. I do hope you get and install the 370cc injectors with your Supra MAF. Right now my 305cc injectors are peaking at a PERFECT 80% duty cycle which is ideal for my current configuration. I am however, working on somethings that it going to boost my protential HP up a bit and I may over tax my 305cc injectors. If you install the 370cc injectors and you confirm what that one other guy's results are I will be a happy camper. That means that I will be able to use the 370cc injectors which should work nicely with my projected HP when I complete my next series of upgrades to include my new engine and some other cutting edge stuff if I have the guts to follow through with it.

Do let me know how the 370cc injectors work out on the hot start. I am dying to know.

Gadget

www.GadgetOnline.com

ravencr

Thanks Gadget! I will keep you posted, and will I be able to use any of this cutting edge stuff you are talking about for your new engine?

Chris