I will be dropping my new built motor in shortly. Before swapping to the MS fuel system, I plan to simply swap the engines and leave the fuel system until I gather the parts needed from Slick and whatnot.

With that said, I am currently running the SFMU with the dark spring and large disk along with 310cc injectors. Currently my fuel pressure at 5psi of boost is 55psi. My question is, do I need to make any changes to the SFMU as far as disk, spring, or fuel pressure goes if I raise the boost to 10psi. Won't the SFMU's (rising rate) simply compensate from the vacuum signal and raise fiel pressure accordingly?

Let me know if Im on the right track - thanks.
(Yes I searched, there are a shit ton of fuel pressure and SFMU threads)

If the AFR is already on track with the current rising rate at your current boost pressure, it should be able to work up to 10 PSI. Give it a try... Bring it to WOT in like 4th gear or something starting from 2000 RPM's so it slowly spools, watching the mixture. If it goes lean, then you will have to do something to the FPR.

what was your outcome Ryan? Reason why I ask is because I am planning a bottom end rebuild here pretty soon, but just bought a slighted used s16g to replace my old s16g. Come to find out the person that sold me it...didn't tell me it had a 10psi wastgate. Long story short what disk/spring did you end up going with to run this. I have the 310cc/SFMU/walbro 255 and was going to run it rich on purpose to try and prolong the rebuild as long as I could. I have searched as well and this post is the closest thing I have found to what I am looking for.

Anyone let me know...please if anyone is running 10psi on stock internals with this fuel setup....lemme know...thanks!

You might want to PM Matt (xtremers). I know that he ran up to 12 psi on 310s with the sfmu, although I know that he says at that hi boost level, the injectors were maxed out.

I run an SFMU and an SAFC with the 310's. The SFMU is running the 12:1 disk and the dark spring, along with the bleeder vlave closed. I also run the walbro255. The 310's technically max out at 14.5 psi, but I play it "safe" and run about 13psi right now each day. Most people with these injectors run 22psi or so at idle, but I run about 30psi and lean the SAFC lo-throttle setting down to -20%. Ive datalogged it and the STFT is just fine. My car doesn't like idleing with insanely low fuel pressures. I think my fuel pressure at 13psi is about 90psi...maye even 95. But I really tune off of my digital A/F gauge and my EGT's. Digital A/F resides at about .95V - .97V...somewhere around there give or take what gear Im in...but a tad rich regardless. The EGT's dont go over 1500, 1450 usually....

The only issue Im having now is a small coolant leak I havnt had time to pin point and my vacuum is a tad low at only 14in/hg instead of 18ish....but it runs like a champ fully built at 13psi with the underdrive pully and 60mm TB...

I am just seeing how long I can get away with running 10psi on stock internals by running it a bit rich until I get it rebuilt. See I was running 7psi on my old s16g, but since I bought a slightly used one the wg came preset to 10psi and the wg's are not exhangeable. So I was trying to get away with 10psi for as long as I could or until I get everything gathered for my rebuild. Anyone running 10psi on stockies?

When you did your rebuild...what all did you upgrade and/or replace?

Originally posted by Aggression
I am just seeing how long I can get away with running 10psi on stock internals by running it a bit rich until I get it rebuilt. See I was running 7psi on my old s16g, but since I bought a slightly used one the wg came preset to 10psi and the wg's are not exhangeable. So I was trying to get away with 10psi for as long as I could or until I get everything gathered for my rebuild. Anyone running 10psi on stockies? When you did your rebuild...what all did you upgrade and/or replace?

How r u running 10psi on stockies, wat is your tuning methos so that u dont run too rich or lean? just and SMFU????

Originally posted by Aggression
I am just seeing how long I can get away with running 10psi on stock internals by running it a bit rich until I get it rebuilt. See I was running 7psi on my old s16g, but since I bought a slightly used one the wg came preset to 10psi and the wg's are not exhangeable. So I was trying to get away with 10psi for as long as I could or until I get everything gathered for my rebuild. Anyone running 10psi on stockies? When you did your rebuild...what all did you upgrade and/or replace?

First off, I don't recommend running 10psi pom stock internals whatsoever. I wouldn't go over 8psi if I were you. The piston ringlands will go and you'll lose compression.. There have been people taht have ran 10psi and more on stock internals....but eventuallly they all go... hell some motors blow on 5-7psi... the engine just isn't designed to handle that kind of power.

My motor was actually the motot that was in Jason_ESi-T's Black Eagle Talon. He is an older member, and he sold his car to a friend of mine. My friend totalled the car and I bought the engine and dropped it in. Here are the specs:

JE 8.8:1 pistons
Crower rods
Crankscraper
Mellings oil pump
Limited Slip Differential in tranny
ARP head studs
Custom 6 puck ceramic clutch
AFX Underdrive pully

Thats the basics of a trypical rebuild. Rods and pistons that can handle the power, a crankscraper to keep oil where it should be, good pump, LSD to help the traction with high boost, a clutch that can hold the power, and I threw in an AFX Underdrive pully just to gain a few extra horses. You also need an Intercooler than can do the job, I'm running a 26" bar and plate IC with 3" inlet and outlet with custom intercooler piping.

did you do any head work? Or is your head completely stock? Did you replace any belts while you had it out?

I am ordering a built block now so if it blows then it blows!

I am going to try and run it a bit rich for the time being to try and preserve it on 10psi as long as I can!

Originally posted by Aggression
did you do any head work? Or is your head completely stock? Did you replace any belts while you had it out? I am ordering a built block now so if it blows then it blows! I am going to try and run it a bit rich for the time being to try and preserve it on 10psi as long as I can!

The head on my engine is completely stock, but it was rebuilt when the block was being built. I replaced all belts.

Originally posted by Ryan_Hes

Originally posted by Aggression My motor was actually the motot that was in Jason_ESi-T's Black Eagle Talon. He is an older member, and he sold his car to a friend of mine. My friend totalled the car and I bought the engine and dropped it in.

Damnit... you need to kick your friend in the nuts. I loved that car.

Oh and BTW, I built that custom clutch in your car a long time ago :)

Originally posted by Ryan_Hes
My motor was actually the motot that was in Jason_ESi-T's Black Eagle Talon. He is an older member, and he sold his car to a friend of mine. My friend totalled the car and I bought the engine and dropped it in.

Originally posted by Matt_95tgs
Damnit... you need to kick your friend in the nuts. I loved that car. Oh and BTW, I built that custom clutch in your car a long time ago :)

What is the story behind him totaling it?

He was driving early in the morning about 8am. He was on a road that was a broad right turn... it was nealy straight...but still bent right a tad. He said that he was going about 45 and wasn't doing anything crazy...and a girl in a lancer cut him off and he had to brake hard...then he said the steering wheels become uncontrollable and it veered off the road to the left at 45mph...just missed one tree and hit another tree head on. The tree was young and snapped when the car hit it, but it was strong enough that is totalled the car. Impact of the tree would be comparable to hitting a street light post at about 18mph..thats the amount of give Id say it had...if you can imagine what Im saying. Lots of people are skeptical about what really happened that day...some say FWD cars don't just "lose" control that easily..especially if you aren't driving aggressively.

In my head, I imagine boosting around this borad right curve...maybe going 60mph and over adjusting the wheels to help hold the line on the road while understeering...then when cut off...brakes applied...front wheels snap but are over corrected...car jars to the right and he could have overcorrected left sending him off the road. I've felt understeer in our cars and what it can do...and thats what I imagine...but hes a good friend of mine and says that wasn't the case.

I dont think anyone will ever know EXACTLY what happened...but its history..so it is what it is.