Getting 42# SVO's to idle.....
 

About the setup. dual Walboro 255LPH intanks with LS1speed billet FPR/Fuel Rails/Fuel filter setup. Braided steel fuel lines. 42#SVO injectors. Forged 346 with stage III heads and TR 224/224 .561 .561 114LSA cam. THunder racing high volume oil pump. TurboTech T60 turbo kit.

My car is at the shop currently and we tried firing it up yesterday. The IFR table was at 8 across the whole kPA range. Ran perfect @ 1200RPM...lol....
Fuel pressure is @ 65PSI at Idle. Tried lowering the idle back to 900RPM and it choked. Tried to start it up and it would barely start up and then die again within seconds......might need a little more time to learn I guess??? The IFR table seems pretty high enough to not bog it @ idle.

Didn't manage to have Autotap to check the LTFT yet though. We will be doing that tomorrow.

Should I raise my IFR Range some more? Or should I leave it and try to get the car to idle with the current 8flat IFR range?

I think 8 is too much. Like, way too much. I don't have all the motor work you do, but I do have svo 42's and a walbro with 60 psi idle pressure, but my ifr table is mid to upper 4's. If you can, hook a wideband up, I'd bet money its super lean.

do you have an adjustable boost/vac referenced regulator?

that will help a lot with tuning, as stock, the injectrors esentially get smaller as your lose manifold vacuum, changing the differential pressure between the 2, with a vac system, you will have a XXpsi between the rail, and manfold all the time.

Ryan.

lower your fuel pressure to something reasonable or at least to stock and your idle will be much better.

your set up sounds just like i did mine a year ago, i run 50psi fuel at idle/60 at 0 manifold pressure/1psi per psi boost after that.

after you do that you should be able to run in the 5.5 range.

just thought of something else.. you aren't running both pumps at idle are you???

I think so. I think it's too much fuel pressure @ idle.....i mean 65PSI is what the fuel pressure gauge is reading from the FPR.

We flashed the stock IFR table back. It wouldn't idle, but it would rev when you gave it gas. Scaled it 110%. Same thing.....barely holding idle than it died. Scaled it 110% again. Idled, but when you gave it gas, it would choke like something is clogged or something, it won't rev up.....

I'm clueless.........

Running the SVO 42#'s at 65 psi would come out to be 51.64# injectors. In that case I would scale the stock IFR by 180% to get a starting reference point then tune from there.

that is too much at idle, imho.

Personally, i would run stock at idle, as the maximum. 58 static.

if it was me, and your forced induction, i would run 58 at 0 manifold vacuum, and have it boost/vacuum referenced.

Ryan.

exactly slow...

mekka, dont be clueless.. turn off one of the pumps ASAP (your return system cannot return that much fuel at idle) make it come on under boost via hobbs or a window switch or a wot switch or somethin..

after that, use the regulator to regulate the pressure DOWN

you will see your problem 'magically' dissapear... the flowrate should then be close at 5.51.

thanks for the tip, mighty. You've been a big help to me before. I'll talk to the shop guys tomorrow to see if they can hook up the second pump to come on under boost. Shouldn't be hard (???). Seems to make sense. We had the FPR turned ALL THE WAY DOWN as well when it read 65PSI. Forgot to mention that. oops.

I'll go shopping for a Hobbs switch as well.

Thanks as well to everyone else. Hopefully I can use this information to get my car up and running. It's almost ready! :burn:

I'll keep you guys updated.

your return line is just too small to run 900hp of fuel back through it.. have one pump running at idle and you should have no problems regulating the fuel back down to something normal.

running the second pump off of a hobbs switch and a relay is about as easy as it gets.

also thanks for he props.. its nice to be appreciated. :)

UPDATE:

The car runs great, just had to mess with the tuning. Fuel pressure is @ 50 PSI on startup and goes to 60 PSI.