What injectors to use?

[PorterzSupra]

I have a 88 Supra with 3 1/2 inch from turbo, boost controller, intake and Lex A/F on about 15-18 PSI. I am replacing the injectors and I dont know what size to go with. I have seen 550cc (stock on a 93-98) 650, 750 and 850 for sale. I know ppl that have gone with 550 but why not go higher? im running higher boost then most what should I use?

 

[MK3Brent]

I know ppl that have gone with 550 but why not go higher? im running higher boost then most what should I use?

Stick with 550's.

If you're staying with the AFM, idling shouldn't be an issue.

 

[MDCmotorsports]

Yup. Brents got you coverd. 550's will work.

If you're planning on making over 500 hp or so (I think) then go with something bigger.

 

[rakkasan]

Yup. Brents got you coverd. 550's will work.

If you're planning on making over 500 hp or so (I think) then go with something bigger.

Let me ask an additional question. I plan on going with a 60-1 CT-26 for the time being (450hp), then going with a larger turbo later with a goal of 600hp. Can I buy 680 injectors & back a bunch of fuel out with my SAFC while using the CT, or will the 680 prove to be too much & cause me to run pig rich no matter what I try to take out (hitting the bottom limits of the SAFC)?

 

[shaeff]

with an AFPR and an SAFC, you should be able to tune the car well enough not to be running ridiculously rich. just lower the fuel pressure alot, and monitor it with a wideband!

-shaeff

 

[IHI-RHC7]

Pulling fuel adds Timing!!!!
Get a maft. Pick your injectors for your power goals, monitor your timing!
How? MAFTPRO!!! of course!

 

[T34418L3ONE]

hehehe, maftpro will be mine, oh yes it will be mine.........

 

[IHI-RHC7]

Porter, you haven't been running 15-18 psi through the lexus with stock injectors have you?

 

[IJ.]

"damn 7m's gonna get a 1J"

 

[rakkasan]

Pulling fuel adds Timing!!!!
Get a maft. Pick your injectors for your power goals, monitor your timing!
How? MAFTPRO!!! of course!

Pardon me if I sound naive, but I've never heard of that. How would the ECU know to pull timing if you scale back the KV reading with a SAFC? Controling fuel has been hard for me to grasp, it evades me. :nono:

BTW, I have maft (the standard maft, not maft-pro)