fuel set-up

[dsm9]

i have a 97 420a with turbo
for my fuel system i have accel 450s a walbro 255 fuel pump and safc
however i see that some beleive this is a bad setup.
the only time my car has ever bogged was when it was lean but after the 450s it has never bogged
so what problems could i face with just the 450s, 255 fuel pump and safc( no fcd or missing link or fpr)
thanks

 

[Gamble97]

How much boost?

 

[dsm9]

i had 5 pounds before the ring landings blew after it overheated but now its getting built and i will run 10 daily

 

[tegster1]

You MUST have an FCD or missing link to run any boost at all. I dont have experience with an safc or injectors so I will let someone else answer that part.

 

[rstare]

I have the same thing; I don't need a FCD either. I guess there are just random occurances where one isn't needed.
The problem with using the SAFC on 420a's is the fact that the FCD is already altering the Map sensor signal. If your map sensor signal isn't being altered then it would seem that a SAFC wouldn't be a bad choice. It's not going to be an easiest way though. It's going to take alot of tweeking to get it right.
Do you have a wideband?

 

[dsm9]

yessir aem uego
i mean ive never had any problems but i was reading through the threads and some said it wouldnt work
i just wanted to make sure that my set up wouldnt cause a problem sometime

 

[kongo]

what fuel pressure regulator u using,if u dont have one ## going to be running pig rich.U also going to need a fcdor missing link

 

[dsm9]

naw bro i dont have an fpr, fcd or ML
and my tune is fine (basic street tune)
ill get it retuned after i get my engine back
but i was wondering if im like using unneccesary gas at vacuum or something?

 

[VelocitàPaola]

Depending on how well your S-AFC is tuned, your idle mixture may or may not be overly rich. The S-AFC is somewhat limited in ability, though, so in all likelihood the AFR under vacuum won't be spot on.

 

[rstare]

So what are your AFR's?
If there good then regardless of what your using, it's doing fine.

 

[silvreclips]

Wow I cant even believe the car is running decent like that. So you blew the motor and put in a built one. I would at least get a SFMU to control fuel pressure. Then use the SAFC to lean out the spots that get a little bit rich. This would be the best way to go w/out running MS or something like that. Then you will just have to worry about timing advance once you start getting to around 15psi. I ran the SFMU/440s all the way till 18psi on a 16g before I ran out of fuel.

 

[dsm9]

yeah man my afr is fine or when its not i tune the safc and it becomes fine...
but yeah i never had any problems until i upped the boost and it got lean it would bogg
but that was before the 450s and 255
what kinda sfmu would you suggest?

 

[Ajax]

12:1 disk or get a AFPR but you have a 97 with the return (fpr) by the tank so it cost a little more to get a fuel line to the engine bay.

 

[papastalon]

450cc injectors might be to large with 12:1 for a SAFC to tune. My buddy has 24lbs injectors on a 12:1 Using no fuel management running 15psi on a evo3 16g. Wideband runs between A/R 12.2-12.6 at full boost. But u have to unplug the coolant temp sensor and the computer will run a richer map. I never used a SAFC but it should be able to give u a better tune at idle than his did with 24lbs . It ran A/R 11.5 at idle. The factory timing map is your limit. This car had meth injection and never could get it past 17psi without knock so we just back it down to 15psi from there. Car ran high 12s on 245/40R17 streets radials. Theve Grenaded couple of diffs at the track so be warned.

 

[dsm9]

with the safc to tune and by reading the afr given to me by the aem uego wideband i can set my afr to whatever i want... if i turn the fuel % down my afr becomes a little more lean and if i turn the fuel % up it sends more fuel (at a certain rpm and throttle position) causing the afr to become more rich
ive never had any problems and i dont think im goin to
but i just wanted to hear some suggestions

 

[papastalon]

What turbo are you running?

 

[rstare]

If you have your AFR's tuned good then you will be fine with your 10psi daily.

 

[silvreclips]

But u have to unplug the coolant temp sensor and the computer will run a richer map.

That is a terrible idea and no one should follow this.


dsm9 - The SFMU is adjustable so you can change the rise rate of the unit with different size injectors.

 

[dsm9]

That is a terrible idea and no one should follow this.


dsm9 - The SFMU is adjustable so you can change the rise rate of the unit with different size injectors.

hahaha

thanks man ill look into one.
i should have my car up tomorrow or saturday.
im so excited i havent driven it really since july.