450's and SAFC II??

RoaSted · 07-24-2006, 07:17 AM

Im wondering if 450's and tune with a SAFC will get me up to around 15-18 psi. If not, then say i get bigger injectors is it possible? I have heard that many people have ran this type of setup for several years and have been ok and the cars are still running very well. I have put lots of work into the bottom end so its good to take the boost. Im wrapping up the car cause NOPI is coming up soon so I need all your help. Mod list below just in case

Hahn stage II (16g)
crane turbo cams
Underdrive crank pulley
JE pistons,rings, eagle rods etc...
Cometic gasket 8:8:1
Walbaro 255
Slightly ported head

BigRand · 07-24-2006, 12:03 PM

Its not so much the SAFC you have to worry about, because that is going to take away fuel when you have too much.

You need to figure out the type of fpr you are going to use.

You could use a regular 1:1 fpr, or a SFMU

go to www.2gnt.com mods/tech, and read everything about the fuel setups. Don't forget to check out corbrins page.

RoaSted · 07-24-2006, 07:42 PM

Hey man yeah i was told that i would need a SFMU. I was gonna get that but i wanted to make sure that the 450's would be plenty to run bout 15-18 psi. I will also have a wideband hooked up to thanks for the link man

VelocitàPaola · 07-25-2006, 11:13 AM

Yep, I'd say 450's are OK for that amount of boost. Just watch your wideband and make sure you don't lean out anywhere. You can adjust that S-FMU for any rich/lean conditions, and like Rand said, the S-AFCII will help a little with any richness.

XMasta19 · 07-25-2006, 07:50 PM

The ford racing green top 42#'s I have and others have used seem to max after about 12-13psi. Terry has said he sees max duty cycle on his 550's at around ~15psi.

VelocitàPaola · 07-25-2006, 09:34 PM

Really? Is that with an Aeromotive type AFPR, or an S-FMU? Keep in mind that the S-FMU will dump a little more fuel into the mix than the 1:1 Aeromotive types.

XMasta19 · 07-26-2006, 02:52 AM

Terry using a 1:1 with megasquirt and 550's, and Mike on 2gnt using an S-FMU with the 440's.

VelocitàPaola · 07-26-2006, 07:45 AM

That doesn't seem right to me, but I'll take your word for it. Do you happen to know what duty cycle you're running at with those 440s?

In light of Xavier's information, I revise my recommendation: I'd go with 550s to be on the safe side. The S-FMU should allow you to squeeze a little more fuel out of them; possibly up to 16psi or so.

XMasta19 · 07-26-2006, 11:54 AM

Well I am installing my megasquirt this weekend, so I will be able to tell you then I guess.

It was the homie on 2gnt that told me about his 42#'s....
"Yep, about 12-13psi. I tried 14-15 psi but the duty cycle would hit 100% around 6k rpm... Thats why I just got some 60#ers"

RoaSted · 07-31-2006, 12:18 PM

hey thanks guys sorry its taken me so long to get on here to respond. Been working too much. Ok well thats good to know i just wanted to make sure that my car would be ok to run with the SFMU SAFC and the 450's my friend was saying that i was gonna blow it. I wanted to make sure that it could run fine with what i have. He is a honda driver so....

thanks again guys