First off, thanks to everyone who helped me identify my Turbonetics turbocharger the other day. I've been reading up on size injectors to use with the T04B-H3 turbine but everyone is pushing for 350hp and I want to keep it 300-320. I've got an rtek 2.1 and I know they support 720s but I've read you can use bigger injectors.

Would 4 720cc injectors safely support 300hp on a stock port series 4 so should i go with 1000cc secondaries? or would bigger be safer?

350hp sounds nice but this is in an 83 and i think that would be a bit much for what I do with the car.

Thanks for any advice yall can offer.

 

I would go with bigger secondaries only because that way you can have better idle quality control with the smaller primaries.

 

Thanks, ive seen some folks use 550s primaroes and then 1200cc secondaries. Is that what you mean?

 

The first problem is the rtek... don't do that to yourself. Your power goal is stock with an exhaust and an intercooler. Going single isn't in any way logical if that's your intent. Not even from a maintenance standpoint does it make sense. I dont think its even possible to make that little of power on a single of any size without literally choking the motor.

But to answer your question, stock injectors run at a higher base pressure will more than likely do what you need. That's a nonsensical approach but..... it would be inline with what you're trying to do. If you want to sprinkle some logic into the mix, keep the stock primaries and go with ~1000 secondaries. You only "need" to upgrade the secondaries for what you're trying to do.

Reconsider your objective and execution... please...

 

the 4x700cc setup is equivalent to a stock FD, which was 550/850; and it can do 320whp pretty easily. if you bump fuel pressure maybe a little more.
realistically the stock hotside is going to limit the thing to about 320hp, so no need for 500hp of injectors.

 

I'm curious about 300hp with the factory turbo, I've read 240hp is about the most it produces at 11psi. With some folks.saysong 12psi. i chose the rtek bc plug and play, with a usdm harness. what ecu would you recommend? and what brand intercooler I've front-mountws the stock topmount and figured it's time to upgrade .

 

thanks, I was hoping I wouldn't need 1000cc injectors but I wanted a bit of room incase of boost creep. its a 83model so 320hp.is alot.of power.

 

the stock turbo can only do about 31lbs/minute of airflow no matter what you do, which is about 250hp.
on my car this was about 13psi at 5000rpm, tapering down to 7.75psi at 6500.

the larger compressor flows more, just the H trim compressor on its own can do 46lbs min,
on my car, with a smaller V trim wheel in a bored out stock housing, ~41lbs min was like 12.9psi at 6000rpm, 46 would be more, probably ~13psi at more like 7000rpm

its also likely that something else will keep it from actually flowing 46lbs min, again with mine the exhaust silencer only flows about 38lsb min, so ~9psi at 7000rpm is the most it'll do no matter what
i'm running stock FD injectors, 550/850 which is lile 4x700cc, and duty cycle is in the low 80's, and its a little rich still. hoping to pull the silencer out and got for the 350hp@13psi my turbo is rated at (it'll be close!)

a stock turbo setup is a little different in that there is no headroom, ~350hp is the most it can possibly do

 

that's great info. my turbonetics uses the stock size hotside. my exhaust is a 2.5" dowpipe to 3" to 2.5" at the rear end to a racing beat rotor muffler. until heavy throttle it go to 10-11 psi, I've got an adjustable fpr.. I'm Wanting 10psi with new turbo and testing the wastegate,it starts to open around there

 

stock twins are capable of 330-350 with the appropriate supporting mods very easily at 12-13psi. A1, C1 and G1 have the same potential to varying degrees with the G1 having the highest potential.

For what you're doing a power fc will be more than enough.

easiest intercooler option will be any aftermarket stock mount. It requires the least amount of work.

An all stock fd has ~100hp locked away from supporting mods with stock equipment. It's easily accessible in the sense that it's not pushing anything to a limit or asking too much of the turbos or anything. You can have a 330whp fd in stock-ish form and it will run all day without issue.

 

not talking about a fd

 

I think I should've specified im using an 88 13bt in an 83 model car. lol

 

My fault entirely for assuming 🤦🏾‍♂️

Still stand by the power fc though

 

I've heard alot of positives about the power fc